Research Group Publications

  • Sandeep Yadav, Sanjukta Pahar And Sakya S. Sen*, Benz-amidinato calcium iodide catalyzed aldehyde and ketone hydroboration with unprecedented functional group tolerance, Chem. Commun., 53, 4562 - 4564 (2017).
  • Nasrina Parvin, Rajarshi Dasgupta, Shiv Pal, Sakya S. Sen* And Shabana Khan*, Strikingly diverse reactivity of structurally identical silylene and stannylene, Dalton Trans., , (2017), DOI:10.1039/C7DT01055A.
  • Ruchi Jain, Edwin Gnanakumar And Chinnakonda S Gopinath, Mechanistic Aspects of Wet and Dry CO Oxidation on Co3O4 Nanorod Surfaces : A NAP-UPS study, ACS Omega., 2, 828 - 834 (2017).
  • Anjani Dubey, Kasala Prabhakar Reddy And Chinnakonda S. Gopinath*, Ambient CO oxidation on in-situ generated Co3O4 spinel surfaces with random morphology, ChemistrySelect., 2, 533 - 536 (2017).
  • Debasmita Sardara, Manideepa Senguptab, Ankur Bardoluib, Md. A. Ahmedc, S.K. Neogic, Sudipta Bandyopadhyayc, Ruchi Jain, Chinnakonda S. Gopinathd And Tanushree Balaa*, Multiple functionalities of Ni nanoparticles embedded in carboxymethyl guar gum polymer: Catalytic activity and superparamagnetism, Applied Surface Science., 405, 231 - 239 (2017).
  • Minu Mohan, Vikas Nandal, Sanish Paramadam, Kasala Prabhakar Reddy, Sekar Ramkumar, Sumanshu Agarwal, Chinnakonda S Gopinath, Pradeep R Nair And Manoj AG Namboothiry, Efficient Organic Photovoltaics with Improved Charge Extraction and High Short-Circuit Current, J. Physical Chemistry C., 121, 5523 - 5530 (2017).
  • Milan K Bisai, Sanjukta Pahar, Tamal Das, Kumar Vanka* And Sakya S. Sen*, Transition metal free catalytic hydroboration of aldehydes and aldimines by amidinato silane, Dalton Trans., 46, 2420 - 2424 (2017).
  • Yogita Soni, E. A. Anumol, Chandrani Nayak, Leonard Deepak Francis And C. P. Vinod, "A Convenient Route for Au@Ti-SiO2 Nanocatalyst Synthesis and its Application for Room Temperature CO Oxidation", The Journal of Physical Chemistry C., (just accepted), (2017).
  • A Lazar, CP Vinod And AP Singh, Exploration of amination reactions on highly extendable active sites of Pd (II)-3-allylsalicylaldiminophenol (ASIP) complex over thiofunctionalized SBA-15, Microporous and Mesoporous Materials., (just accepted), (2017).
  • Manisha Dohade And Paresh L. Dhepe, Efficient hydrogenation of concentrated aqueous furfural solutions in to furfuryl alcohol under ambient conditions in presence of PtCo bimetallic catalysts, Green Chemistry., , (2017), DOI:10.1039/C6GC03143A.
    One of the biomass derived significant chemical furfural (FAL) can be hydrogenated to yield industrially important platform chemical, furfuryl alcohol (FOL). Although heterogeneous catalysts based methods are known to yield FOL from dilute solutions of FAL, those mainly operate at higher temperatures and/or high pressures of hydrogen and in presence of organic solvents. In this work, we employ bimetallic PtCo/C catalysts with varying metal concentrations to achieve maximum possible FOL yield (100%) at 35 oC under 0.1 MPa H2 in water. With concentrated FAL (40 wt%) at 50 oC and under 1 MPa H2 pressure, 86% yield for FOL was observed. Moreover, efficient recycling of catalyst in at least 4 runs with marginal loss in activity due to handling error and isolation of FOL in pure form confirmed by NMR and HPLC is attractive. The characterization of catalysts with several physico-chemical techniques (XRD, TEM, XPS, ICP,TPR) reveal the presence of electron rich Pt and ionic Co species in proximity with each other and those work synergistically to facilitate accomplishment of maximum possible yield of FOL under ambient conditions and in water medium.
  • V. S. V. S. N. Swamy, Sandeep Yadav, Shiv Pal, Tamal das, Kumar Vanka* And Sakya S. Sen*, Facile access to a Ge(II) dication stabilized by isocyanides, Chem. Commun., 52, 7890 - 7892 (2016).
  • Sandeep Yadav, Sumana Saha And Sakya S. Sen*, Compounds having Low-Valent p-Block Elements for Small Molecule Activation and Catalysis, ChemCatChem., 8, 486 - 501 (2016).
  • Sandeep Yadav, V. S. V. S. N. Swamy, Rajesh G Gonnade And Sakya S. Sen*, Benz-amidinato Stabilized a Monomeric Calcium Iodide and a Lithium Calciate(II) Cluster featuring Group 1 and Group 2 Elements, ChemistrySelect., 1, 1066 - 1071 (2016).
  • Rüdiger Bertermann, Julian Böhnke, Holger Braunschweig, Rian D. Dewhurst, Thomas Kupfer, Jonas H. Muessig, Leanne Pentecost, Krzysztof Radacki, Sakya S. Sen And Alfredo Vargas, Dynamic, Reversible Oxidative Addition of Highly Polar Bonds to a Transition Metal, J. Am. Chem. Soc., 138, 16140 - 16147 (2016).
  • Anjani Dubey, Sadhu K. Kolekar And Chinnakonda S. Gopinath*, C-H Activation of Methane to Formaldehyde on Ce1-xZrxO2 Thin films: A step to bridge the material gap, ChemCatChem., 8, 3650 - 3656 (2016).
  • Richa Chaudhary And Paresh L. Dhepe, Solid base catalyzed depolymerization of lignin into low molecular weight products, Green Chemistry., , (2016), DOI:10.1039/C6GC02701F.
    For biorefinery concept to become commercially viable, it is essential to value-add lignin which is the only naturally available aromatic polymer. A one-pot depolymerization of lignin into reactive substituted phenolic compounds (platform chemicals and octane enhancers) with low molecular weightis of paramount interest and for that development of environmentally benign method is necessary. Herein we report, depolymerization of high molecular weight lignin (60,000 Da) over various recyclable solid base catalysts at 250 oC in 1 h. Under this conditions, most of the zeolitic catalysts (NaX, NaY, NaP) showed very high yields of low molecular weight products than other catalysts (MgO, CaO, HT, HAP). But particularly, over NaX maximum yield (51%) of low molecular weight products was achieved. Identification and quantification of products was done by GC, GC-MS, HPLC, LC-MS, CHNS, NMR and FT-IR techniques. The revelation of retention of most of the functional groups on products present in lignin is done by FT-IR studies. It is observed that efficiencies of catalysts were dependent on pH, cation, type and concentration of basic sites etc. A unique study on products adsorption capacities on solids was done and it is recognized that as strength of basic sites increases adsorption enhances.
  • Leena George, Athira K. Kunhikannan, Rajith Illathvalappil, Divya Ottoor And Sreekumar Kurungot and R. Nandini Devi, Understanding the electron transfer process in ZnO–naphthol azobenzoic acid composites from photophysical characterisation, Phys. Chem. Chem. Phys., 18, 22179 - 22187 (2016), DOI:10.1039/C6CP02908F.
    Semiconductor nanoparticles surface modified with organic molecules capable of visible light absorption and effectively transferring the electrons to the catalytic sites have the potential to be good photocatalysts. ZnO nanoparticles of size ?3 nm are grafted with two azonaphthols, one conjugated and the other non-conjugated. The photophysical properties of modified ZnO indicate an effective electron transfer from the conjugated azonaphthol to ZnO but not in the case of the non-conjugated molecule. It is also observed from lifetime studies that the conjugated molecule stabilises the defect sites on ZnO nanoparticles. It is possible that excited electrons from the conjugated molecule are transferred to specific defect sites in ZnO. This apparently does not occur in the non-conjugated molecule, bringing to focus the importance of the photophysical characteristics of organic modifiers in designing visible light active photocatalysts.
  • Chamundi P Jijil, Moorthi Lokanathan, Sundaresan Chithiravel, Chandrani Nayak, Dibyendu Bhattacharyya, Shambhu Nath Jha, Peram Delli Babu, Bhalchandra Kakade And and R. Nandini Devi, N Doping in Oxygen Deficient Ca2Fe2O5: A Strategy for Efficient Oxygen Reduction Oxide Catalysts, ACS Applied Materials and Interfaces., Just Accepted Manuscript, (2016), DOI:10.1021/acsami.6b11718.
    Oxygen reduction reaction is increasingly being studied in oxide systems due to advantages ranging from cost effectiveness to desirable kinetics. Oxygen deficient oxides like brownmillerites are known to enhance ORR activity by providing oxygen adsorption sites. In parallel, N and Fe doping in C materials and consequent presence of catalytically active complex species like C-Fe-N is also suggested to be good strategies for designing ORR active catalysts. A combination of these features in a N doped Fe containing brownmillerite can be envisaged to present synergistic effects to improve the activity. This is conceptualized in this report through enhanced activity of N doped Ca2Fe2O5 brownmillerite when compared to its oxide parents. N doping is proved using neutron diffraction, UV-vis spectroscopy, X-ray photoelectron spectroscopy and X-ray absorption spectroscopy. Electrical conductivity is also found to be enhanced by N doping which influences the activity. Electrochemical characterizations using cyclic voltammetry, rotating disc electrode and rotating ring disk electrode indicates an improved oxygen reduction activity in N-doped brownmillerite with a 10 mV positive shift in the onset potential. RRDE measurements show that both the compound exhibit 4-electron reduction pathways with lower H2O2 production in N-doped system also N-doped sample exhibited better stability. The observations will enable better designing of ORR catalysts which are stable and cost effective.
  • Sadhu K. Kolekar, Anjani Dubey, Kalyani S. Date, Suwarna Datar And Chinnakonda S. Gopinath*, "An attempt to correlate surface physics and chemical properties : Molecular beam and Kelvin probe investigations of Ce 1-x Zr x O 2 thin films", Physical Chemistry Chemical Physics., 18, 27594 - 27602 (2016).
  • Kalpesh Sorathiya, Biswajit Mishra, Abhishek Kalarikkal, Kasala Prabhakar Reddy, Chinnakonda S. Gopinath And Deepa Khushalani*, Enhancement in Rate of Photocatalysis Upon Catalyst Recycling, Scientific Reports., 6, 35075 (2016).
  • Kshirodra K.Patra And Chinnakonda S. Gopinath*, Bimetallic and Plasmonic Ag-Au on TiO2 for Solar Water Splitting : An Active Nanocomposite for Entire Visible Light Region Absorption, ChemCatChem., 8, 3294 - 3311 (2016).
  • Kandasamy Prabu, Marimuthu Prabu, Ashok Kumar Venugopal, WVY Sai Sandilya, Chinnakonda S. Gopinath* And Thirumalaiswamy Raja*, Effective and selective oxidation of 2-butanol over Mn supported catalyst systems, Applied Catalysis A: General., 525, 237 - 246 (2016).
  • Subhasis Das, Biswarup Satpati, Himani Chauhan, Sasanka Deka, Manoj Kumar Ghosalya, Chinnakonda S. Gopinath And Tanushree Bala*, Seeding of Au on CdSe/CdS nanoplates using Langmuir–Blodgett technique, RSC Advances., 6, 14658 - 14665 (2016).
  • Vinod G. Landge†§, Siba P. Midya†§, Jagannath Rana†§, Dinesh R. Shinde‡ And and Ekambaram Balaraman*†§, Expedient Cobalt-Catalyzed C–H Alkynylation of (Enantiopure) Benzylamines, Org. Lett., 18, 5252 - 5255 (2016), DOI:DOI: 10.1021/acs.orglett.6b02549.
  • Mukesh Kumar, Kiran Soni, Biswarup Satpati, Chinnakonda S. Gopinath And Sasanka Deka*, Exploration of magnetically separable Ag@AgxNiy core/graded-alloy-shell nanostructures, Chemical Communications., 52, 8737 - 8740 (2016).
  • Anand S. Burange, Rakesh Shukla, Avesh Kumar Tyagi* And Chinnakonda S. Gopinath*, Palladium Supported on Fluorite Structured Redox CeZrO4-? for Heterogeneous Suzuki Coupling in Water: A Green Protocol, Chemistry select., 1, 2673 - 2681 (2016).
  • Naveen K. Sathu, Perumal Devaraji And C. S. Gopinath*, Green Leaf to Inorganic Leaf: A Case Study of ZnO, Journal nanoscience and nanotechnology., 9, 9203 - 9208 (2016).
  • Anjani Dubey, Sadhu K. Kolekar And Chinnakonda S. Gopinath*, "C-H Activation of Methane to Syngas on MnxCe1-x-yZryO2 - A Molecular Beam Study", ChemCatChem., 8, 2296 - 2307 (2016).
  • Ambrose A.Melvin, Pradnya A. Bharad, Kavya Illath, Meenu P. Lawrence And Chinnakonda S. Gopinath*, Is there any Real effect of Low Dimensional Morphologies towards Light Harvesting? A Case Study of Au-rGO-TiO2 Nanocomposites, Chemistry Select., 5, 917 - 923 (2016).
  • Kanak Roy, Ruchi Jain, Manoj Kumar Ghosalya, Kasala Prabhakar Reddy And Chinnakonda S. Gopinath*, Three Way Catalytic Converter Reactions Aspects at Near Ambient Temperatures on Modified Pd-Surfaces, Comptes Rendus Chimie., 19, 1363 - 1369 (2016).
  • Anjani Dubey, Sadhu K. Kolekar, Edwin S. Gnanakumar, Kanak Roy, C. P. Vinod And Chinnakonda S. Gopinath*, Porous Thin Films Towards Bridging the Material Gap in Heterogeneous Catalysis, Catalysis, Structure and Reactivity., 2, 1 - 12 (2016).
  • Ruchi Jain, Anjani J Dubey, Manoj K Ghosalya And Gopinath S Chinnakonda , Gas-Solid Interaction of H2-Ce0.95Zr0.05O2: New Insights on Surface Participation in Heterogeneous Catalysis, Catalysis Science & Technology., 6, 1746 - 1756 (2016).
  • Sandip K. Singh And Paresh L. Dhepe, Isolation of lignin by Organosolv process from different varieties of rice husk: Understanding their physical and chemical properties, Bioresource Technology., , (2016).
    The aim of this work was to study the difference in properties of lignins, those (organosolv lignins (ORGLs, 12±3% yield and 93±5% mass balance) were isolated from diverse rice husk (RH) substrates using organosolv procedure (water:ethanol, H2SO4) carried out at 180?C for 1 h. To identify the possible alterations in lignin structures several bulk and molecular level advanced characterization tools were employed. Even though lignins were extracted using common isolation procedure from three varieties of similar species of RH; from XRD, GPC, and elemental analysis it was found that those have comparable properties on bulk level. But molecular level analysis conducted using UV-Vis, ATR, 1D/2D HSQC NMR techniques could help disclose that isolated lignins have varying concentrations of G, H, S and T substructures. Additionally, the double bond equivalence of 4.4-4.7 reveals that few of the aromatic rings are devoid of substituent.
  • Prasenjit Bhaumik And Paresh L. Dhepe, From Lignocellulosic Biomass to Furfural: Insight into the Active Species of a Silica-Supported Tungsten Oxide Catalyst, ChemCatChem., , (2016), DOI:10.1002/cctc.201600784R1.
    A sol-gel synthesized silica supported tungsten oxide catalyst that has Lewis acidity was characterized and employed as a solid acid catalyst in the synthesis of furfural directly from lignocellulosic biomass (isolated xylans and crop wastes). In a one-pot method, 71% furfural formation from isolated xylan was possible using a water/toluene (1:2 v/v) biphasic solvent system at 170°C after 10 h over 10 wt^% WO3/SiO2. The WO3/SiO2 catalyst in the selective conversion of pentosan from crop wastes (bagasse, wheat straw, and rice husk) yielded 72-87% furfural under the optimum reaction conditions. Additionally, the catalyst presented excellent recyclability in at least eight runs after simple water washing. From the catalyst characterization studies, it was suggested that silicotungstic-type acid species are anchored on the WO3/SiO2 catalyst that help to achieve a good catalytic activity.
  • Kandasamy Prabu, Marimuthu Prabu, Ashok Kumar Venugopal, Aswathy Thareparambil Venugopalan, W.V.Y. Sai Sandilya, Chinnakonda S. Gopinath And Thirumalaiswamy Raja, Effective and selective oxidation of 2-butanol over Mn supported catalyst systems, Applied Catalysis A: General., 525, 237 - 246 (2016), DOI:
  • Shyamapada Nandi, Santosh Kumar Singh, Dinesh Mullangi, Rajith Illathvalappil, Leena George, C. P. Vinod, Sreekumar Kurungot And Ramanathan Vaidhyanathan, Low Band Gap Benzimidazole COF Supported Ni3N as highly active OER catalyst, Advanced Energy Materials., , (2016), DOI:10.1002/aenm.201601189.
  • Sandip K. Singh And Paresh L. Dhepe, Ionic liquids catalyzed lignin liquefaction: mechanistic studies using TPO-MS, FT-IR, RAMAN and 1D, 2D-HSQC/NOSEY NMR, Green Chemistry., 18, 4098 - 4108 (2016), DOI:10.1039/C6GC00771F.
    Valorization of a profusely available alternate resource, biomass and in particular its 3-D intricate component lignin into low molecular weight aromatic products are used as platform chemicals and fuel additives, and developing a low temperature catalytic process is imperative in preserving atom efficiency. Ionic liquids, due to their unique properties, offer an advantage to develop such methods under milder conditions. Herein, we show use of –SO3H functionalized imidazolium based various recyclable Brønsted acidic ionic liquids (BAILs) in catalytic quantity under ambient pressure at 120 °C for depolymerization of lignin (60000 g mol?1) into THF soluble products with high efficiency (78% yield, 95% ± 5% mass balance). The decoding of this efficiency by 1D and 2D (HSQC/NOSEY) NMR, FT-IR and RAMAN studies exemplify that the –OH group(s) interact with the electron deficient BAIL cation. The mechanistic insights unraveled in this study open a plethora of opportunities to design catalysts for developing efficient processes.
  • , Nanoscale., , (2016), DOI:10.1039/c5nr06756a.
  • Rawesh Kumara, Sneha Shaha, Jitendra Bahadur, Yuri B. Melnichenko, Debasis Sen, S. Mazumder, C. P. Vinod And Biswajit Chowdhury, Highly stable In-SBA-15 catalyst for vapor phase Beckmann rearrangement reaction, Microporous and Mesoporous Materials., (just accepted), (2016), DOI:10.1016/j.micromeso.2016.07.024.
  • Sakya S. Sen and Herbert W. Roesky, Efficient Methods for Preparing Silicon Compounds, Academic Press, Elsevier., Chapter 17 and 18, (2016).
  • Sreedhala S, Shruti Maheshwari, Betsy K J And C. P. Vinod*, Large Trisoctahedral Au nanoparticles encapsulated inside porous silica catalyses CO oxidation at room temperature: Probing the effect of encapsulation and the role of step atoms and interfaces, Applied Catalysis A: General., 524, 1 - 7 (2016), DOI:10.1016/j.apcata.2016.05.023.
  • Marimuthu Manikandan, Ashok Kumar Venugopal, Kandasamy Prabu, Ratnesh Kumar Jha And Raja Thirumalaiswamy*, Role of surface synergistic effect on the performance of Ni-based hydrotalcite catalyst for highly efficient hydrogenation of furfural, Journal of Molecular Catalysis A: Chemical., 417, 153 - 162 (2016), DOI:10.1016/j.molcata.2016.03.019.
  • Marimuthu Manikandan, Ashok Kumar Venugopal, Atul S. Nagpure And Satyanarayana Chilukuri* and Thirumalaiswamy Raja*, Promotional effect of Fe on the performance of supported Cu catalyst for ambient pressure hydrogenation of furfural, RSC Advances., 6, 3888 - 3898 (2016), DOI:10.1039/C5RA24742J.
  • A C Sunil Sekhar* And C P Vinod *, Gold incorporated mesoporous silica thin film model surface as a robust SERS and catalytically active substrate, Molecules., (invited article for a speciail issue "Coinage Metal (Copper, Silver, and Gold) Catalysis", (2016).
  • G. Jaiswal, V. Landge And D. Jagadeesan* And E. Balaraman*, Sustainable Iron-catalyzed direct imine formation by acceptorless dehydrogenative coupling of alcohols with amines, Green Chemistry(Accepted)., , (2016).
  • Vinod G. Landge, Garima Jaiswal And Ekambaram Balaraman, Cobalt-Catalyzed Bis-alkynylation of Amides via Double C–H Bond Activation, Organic Letters., 18, 812 - 815 (2016), DOI:10.1021/acs.orglett.6b00095.
  • Soumya B. Narendranath, Saranya V. Thekkeparambil, Leena George, Shibin Thundiyil And R. Nandini Devi, Photocatalytic H2 evolution from water–methanol mixtures on InGaO3(ZnO)m with an anisotropic layered structure modified with CuO and NiO cocatalysts, J. Mol. Cat. A., 415, 82 - 88 (2016), DOI:10.1016/j.molcata.2016.01.018.
    InGaO3(ZnO)m series of oxides is found to be active for photocatalytic H2 evolution from water–methanol mixtures. The structure of this series is highly anisotropic with InO6 octahedral layers sandwiching Ga/ZnOn polyhedra. The structural anisotropy in which the conducting layer is spatially separated from the charge generation sites may help in suppressing charge recombination and consequently enhance catalytic activity. The band gaps of the series obtained from absorption spectra are above 3.6 eV and hence they are not active under visible light irradiation. H2 evolution is considerably enhanced under UV light on employing NiO as cocatalyst due to facile electron transfer from InGaO3(ZnO)m to NiO. However, when CuO is used as cocatalyst, visible light activity could be brought out. Due to the very low band gap of CuO, it can act as a sensitizer absorbing in visible light. The band positions become conducive for H2 evolution due to band alignments consequent to electron accumulation in CuO conduction band.
  • S. Sreedhala, V. Sudheeshkumar And C. P. Vinod*, "CO oxidation on large high index faceted Pd nanostructures", Journal of Catalysis., 337, 138 - 144 (2016), DOI:10.1016/j.jcat.2016.01.017.
  • A. B. Vysakh, Anish Lazar, V. Yadukiran, A. P. Singh And C. P. Vinod*, Phenyl acetylene hydrogenation on Au@Ni bimetallic core shell nanoparticles synthesized under mild conditions, Catalysis Science and Technology., 6, 708 - 712 (2016), DOI:10.1039/C5CY02005K.
  • A. B. Vysakh, V. Yadukiran, Anish Lazar And A. P. Singh And C. P. Vinod*, "Synthesis of Au@Ni bimetallic core shell nanoparticle and nanochains in soyabean oil and their catalytic hydrogenation reactions", Chemistry Select., 1 (2), 140 - 146 (2016), DOI:10.1002/slct.201500006.
  • Anish Lazar, Shoy George, Jithesh P R, C P Vinod And A. P. Singh*, Correlating the role of hydrophilic/hydrophobic nature of Rh(I) and Ru(II) supported organosilica/silica catalysts in organotransformation reactions, Applied Catalysis A., 513, 138 - 146 (2016), DOI:10.1016/j.apcata.2015.12.026.
  • Anish Lazar, C P Vinod And A. P. Singh*, A simple, phosphine free, reusable Pd(II)-2,2’-Dihydroxybenzophenone-SBA-15 catalyst for arylation and hydrogenation reactions of alkenes, New Journal of Chemistry., (accepted), (2016), DOI:10.1039/C5NJ02686E.
  • Anjani Dubey, Sadhu K. Kolekar, Edwin S. Gnanakumar, Kanak Roy, C. P. Vinod And Chinnakonda S. Gopinatha, Porous Thin Films Towards Bridging the Material Gap in Heterogeneous Catalysis, Catalysis, Structure and Reactivity., (accepted), (2016).
  • , Molecular Simulations., , (2015), DOI:10.1080/08927022.2015.1067368.
  • , Nanoscale., , (2015), DOI:10.1039/C5NR05715A.
  • Kaliyappan Periyasamy, Venugopalan T. Aswathy, Venugopal Ashok kumar, Marimuthu Manikandan, Rakesh Shukla And Avesh K. Tyagi and Thirumalaiswamy Raja*, An efficient robust fluorite CeZrO4?? oxide catalyst for the eco-benign synthesis of styrene, RSC Advances., 5, 3619 - 3626 (2015), DOI:10.1039/C4RA12355G.
  • Atul S. Nagpure, Ashok Kumar Venugopal, Nishita Lucas, Marimuthu Manikandan And Raja Thirumalaiswamy * and Satyanarayana Chilukuri *, Renewable fuels from biomass-derived compounds: Ru-containing hydrotalcites as catalysts for conversion of HMF to 2,5-dimethylfuran, Catalysis Science & Technology., 5, 1463 - 1472 (2015), DOI:10.1039/c4cy01376j.
  • D. Sardar, S. K. Neogi, S. Bandyopadhyay, B. Satpati, M. Ahir, A. Adhikary, R. Jain, C. S. Gopinath And T. Bala*, Multifaceted core-shell nanoparticles: Superparamagnetism and biocompatibility, New Journal of Chemistry., 39, 8513 - 8521 (2015).
  • Prasenjit Bhaumik And Paresh L. Dhepe, Conversion of Biomass into Sugars, Biomass Sugars for Non-Fuel Applications., 43, 1 - 53 (2015), DOI:10.1039/9781782622079.
  • Trupti V. Kotbagi, Swati L. Pandhare, Mohan K. Dongare And Shubhangi B. Umbarkar , In situ formed supported silicomolybdic heteropolyanions: efficient solid catalyst for acetylation of glycerol, International Journal of Environmental Analytical Chemistry., 02(05), (2015), DOI:10.4172/2380-2391.1000160.
  • P.M. More, D.L. Nguyen, M.K. Dongare, S.B. Umbarkar, N. Nuns, J.-S. Girardon, C. Dujardin, C. Lancelot, A.-S. Mamede And P. Granger , Rational preparation of Ag and Au bimetallic catalysts for the hydrocarbon-SCR of NOx: Sequential deposition vs. coprecipitation method, Applied Catalysis B Environmental., 162, 11 - 20 (2015), DOI:10.1016/j.apcatb.2014.06.031.
  • S. Kale, S.B. Umbarkar, M.K. Dongare, R. Eckelt, U. Armbruster And A. Martin , Selective formation of triacetin by glycerol acetylation using acidic ion-exchange resins as catalyst and toluene as entrainer, Applied Catalysis A General., 490, 10 - 16 (2015), DOI:10.1016/j.apcata.2014.10.059.
  • Wenhao Fang, Sébastien Paul, Mickaël Capron, Ankush V. Biradar, Shubhangi B. Umbarkar, Mohan K. Dongare, Franck Dumeignil And Louise Jalowiecki-Duhamel , Highly loaded well dispersed stable Ni species in NiXMg2AlOY nanocomposites: application to hydrogen production from bioethanol, Applied Catalysis B Environmental., 166-167, 485 - 496 (2015), DOI:10.1016/j.apcatb.2014.11.052.
  • Pavan M. More, Duy L. Nguyen, Pascal Granger, Christophe Dujardin, Mohan K. Dongare And Shubhangi B. Umbarkar, Activation by pretreatment of Ag–Au/Al2O3 bimetallic catalyst to improve low temperature HC-SCR of NOx for lean burn engine exhaust, Applied Catalysis B Environmental., 174, 145 - 156 (2015), DOI:10.1016/j.apcatb.2015.02.035.
  • Prakash Chandra, Dhananjay S. Doke, Shubhangi B. Umbarkar, Kumar Vanka And Ankush V. Biradar , Silica microspheres containing high density surface hydroxyl groups as efficient epoxidation catalysts, RSC Advances., 5(27), 21125 - 21131 (2015), DOI:10.1039/C5RA00374A.
  • A.B. Kulal, M.K. Dongare And S.B. Umbarkar, Sol gel synthesised WO3 nanoparticles supported on mesoporous silica for liquid phase nitration of aromatics, Applied Catalysis B., , 142 - 152 (2015), DOI:10.1016/j.apcatb.2015.09.020.
  • Leena George, Subrahmanyam Sappati, Prasenjit Ghosh And and R. Nandini Devi, Surface Site Modulations by Conjugated Organic Molecules to Enhance Visible Light Activity of ZnO Nanostructures in Photocatalytic Water Splitting, J. Phys. Chem. C., 119, 3060 - 3067 (2015), DOI:10.1021/jp511996z.
    Surface modification of ZnO nanoparticles is identified as a method of modulating surface sites advantageously. ZnO nanoparticles of two different sizes are surface modified with a conjugated organic moiety to enable electron conduction and transfer. Enhanced H2 evolution from water methanol mixtures was observed in the composite systems compared to pristine ZnO under visible light irradiation without any cocatalyst. The system is also marginally active in water splitting in pure water without any sacrificial agents. Photophysical characterisation indicates that even though reducing size into nanoregime affects the band gap detrimentally, modifications by simple conjugated organic molecules assist in enhanced visible light activity. The experimental observations are corroborated with computational studies, which also point to a localisation of valence band maximum of the interface on the organic moiety and conduction band minimum on ZnO.
  • S. Gupta, C. P. Vinod And D. Jagadeeshan, Preparation of mesoporous titanosilicate with isolated Ti active centers for cyclohexene oxidation, RSC Advances., 5, 92371 - 92377 (2015), DOI:10.1039/c5ra18044a.
  • S. P. Midya, M. K. Sahoo, V. G. Landge And P. R. Rajamohanan and E. Balaraman*, Reversed reactivity of anilines with alkynes in the rhodium-catalysed C–H activation/carbonylation tandem, Nature Commun., , (2015), DOI:10.1038/ncomms9591.
  • V. G. Landge, C. H. Shewale, G. Jaiswal, M. K. Sahoo And S. P. Midya and E. Balaraman*, Nickel-catalyzed direct alkynylation of C(sp2)-H bonds of amides: An “inverse Sonogashira strategy” to ortho-alkynylbenzoic acids. Just accepted, Catal. Sci. Technol., , (2015).
  • E. Balaraman, D. Srimani And Y. Diskin-Posner and D. Milstein*, Direct synthesis of secondary amines from alcohols and ammonia catalyzed by a ruthenium pincer complex, Catal. Lett., 145, 139 - 144 (2015), DOI:10.1007/s10562-014-1422-2.
  • A. Nandakumar And M. K. Sahoo and E. Balaraman*, Reverse-hydroformylation: a missing reaction explored, Org. Chem. Front., 2, 1422 - 1424 (2015), DOI:10.1039/c5qo00229j.
  • V.G. Landge, M. K. Sahoo, S. P. Midya And G.Jaiswal and E. Balaraman*, Well-defined palladium(II) complexes for ligand enabled C(sp3)-alkynylation, Dalton Trans., 44, 15382 - 15386 (2015).
  • A. Nandakumar, Siba P. Midya And Vinod G. Landge and E. Balaraman*, Transition-metal catalysed hydrogen transfer annulation strategy to heterocyclic scaffolds, Angew. Chem. Int. Ed., 54, 11022 - 11034 (2015).
  • V S V S N Swamy, Shiv Pal, Shabana Khan* And Sakya S. Sen*, Cations and dications of heavier group 14 elements in low oxidation state, Dalton Trans., 44, 12903 - 12923 (2015), DOI:10.1039/C5DT01912E.
  • Prasenjit Bhaumik and Paresh L. Dhepe, Solid Acid Catalyzed Synthesis of Furans from Carbohydrates, Cat. Rev.-Sci. Eng., , (2015), DOI:10.1080/01614940.2015.1099894.
    The alternative feedstock, biomass (particularly lignocelluloses) having profuse availability is promising for the synthesis of several value-added chemicals which are currently obtained from fossil feedstock. In this review, the synthesis of two extremely significant furan chemicals viz. furfural and 5-hydroxymethylfurfural (HMF) are discussed. In the synthesis of furans from biomass, numerous challenges for instance, use of edible sugars as substrates, selectivity to furans, their isolation in pure form, reuse of catalyst, environmental issues etc. are perceived and in recent past researchers tried to resolve those by developing advance methodologies. This review summarizes latest progresses made in the above mentioned areas comprehensively and also commentary is given on the analyses of results, rationale for observed activity and mechanisms etc. Review also discusses future aspects of this work.
  • Babasaheb. M. Matsagar, Mudassir. K. Munshi, Ashutosh A. Kelkar And Paresh L. Dhepe, Conversion of concentrated sugar solutions into 5-hydroxymethyl furfural and furfural using Brönsted acidic ionic liquids, Catal. Sci. Tenchnol., , (2015), DOI:10.1039/C5CY00858A.
    Catalytic amounts of recyclable Brönsted acidic ionic liquids (BAILs) yielded HMF (73%) and furfural (81%) with high selectivity from highly concentrated solutions of D-fructose (40 wt%) and D-xylose (3 wt%), respectively. With a 6 wt% D-xylose solution, 73% yield was observed. An activity–property correlation of BAIL is established.
  • Ambrose A. Melvin, Kavya Illath, Tanmay Das, T. Raja, Somnath Bhattacharyya And C. S. Gopinath*, M-Au/TiO2 (M = Ag, Pd, and Pt) Nanophotocatalyst for overall solar water splitting: Role of Interfaces, Nanoscale., 7, 13477 - 13488 (2015).
  • Pradnya A. Bharad, K. Sivaranjani And C. S. Gopinath*, A Rational Approach Towards Enhancing Solar Water Splitting : A Case Study of Au – RGO/N-RGO – TiO2, Nanoscale., 7, 11206 - 11215 (2015).
  • Baljeet Singh, Kaustubh R. Mote, C. S. Gopinath, P. K. Madhu* And Vivek Polshettiwar*, SBA-15-Oxynitrides as a Solid-Base Catalyst: Effect of Nitridation Temperature, Angewandte Chemie International Ed., 54, 5985 - 5989 (2015).
  • C. S. Gopinath*, K. Roy And S. Nagarajan, Can we shift and/or broaden the catalysis regime towards ambient temperature?, ChemCatChem., 7, 588 - 594 (2015).
  • S. Raja Ambal, K. Sivaranjani And C. S. Gopinath*, Recent Developments in Solar H2 Generation from Water Splitting, Journal of Chemical Science., 127, 33 - 47 (2015).
  • Manjusha V. Patwadkar, C. S. Gopinath And M. V. Badiger*, An efficient Ag-nanoparticle embedded semi-IPN hydrogel for catalytic applications, RSC Advances., 5, 7567 - 7574 (2015).
  • S. Sreedhala and C. P. Vinod*, Surfactant assisted formation of Ruthenium nanochains under mild conditions and their catalytic CO oxidation activity, Chemical Communications., 51, 10178 - 10181 (2015), DOI:10.1039/C4CC09430A.
  • D. Mullangi, S. Nandi, S. Shalini, S. Sreedhala , C. P. Vinod And R. Vaidhyanathan, Pd loaded amphiphilic COF as catalyst for multi-fold Heck reactions, C-C couplings and CO oxidation, Nature Scientific Reports., , (2015), DOI:10.1038/srep10876.
  • Sumbul Rahman, S. A. Farooqui, Aditya Rai, Rawesh Kumar, Chiranjit Santra, Vinod C P, Gopala Ram Bhadu, Debasis Sen, S. Mazumder, Sudip Maity And Anil Sinha and Biswajit Chowdhury, Mesoporous TUD-1 supported indium oxide nanoparticles for epoxidation of styrene using molecular O2, RSC Advances., (Just Accepted), (2015), DOI:10.1039/C5RA03400K.
  • Vysakh A. Bharathan, Chinchu Lizen Babu And C. P. Vinod*, "Demonstration of Synergistic Catalysis in Au@Ni Bimetallic Core Shell Nanostructures", J Phys Chem C., 119 (15), 8138 - 8146 (2015), DOI:10.1021/jp5128089.
  • A. C. Sunil Sekhar, K. V. Ziyad, Y. Soni And C. P. Vinod*, Activity enhancement on Titanium incorporation: Au@Ti-SiO2 core shell nanocatalysts for CO oxidation reaction, ChemCatChem., 7 (7), 1222 - 1230 (2015), DOI:10.1002/cctc.201402954.
  • S. Sreedhala, V. Sudheeshkumar And C. P. Vinod* , Oxidation catalysis by large trisoctahedral gold nanoparticles: Mind the step!, Catalysis Today., 244, 177 - 183 (2015), DOI:10.1016/j.cattod.2014.02.049.
  • Prasenjit Bhaumik And Paresh L. Dhepe, Effects of careful designing of SAPO-44 catalysts on the efficient synthesis of furfural, Catal. Today., 251, 66 - 72 (2015), DOI:10.1016/j.cattod.2014.10.042.
    Considering the growing importance of furfural, it is necessary to develop a robust solid acid catalyst for the conversion of xylan (hemicelluloses) into furfural in a one-pot method. In this study, the effects of various components (Si, Al and P) and crystallization time on the preparation of acidic materials and their properties are extensively described. It is seen that with the increase in crystallization time (0, 48, 96, 176 h) during the synthesis of silicoaluminophosphate (SAPO-44), materials morphology changes from amorphous to AFI to CHA and the best activity for furfural synthesis (82%) from xylan was observed with SAPO-44 catalyst aged for 176 h. Since, acidity in the SAPO-44 is guided by the incorporation of Si in the ALPO framework, study on Si molar concentration (0.8, 1.0, 1.2, 1.4 and 1.6) in SAPO-44 was carried out and it was observed that SAPO-44 having 1.0 mole of Si content is the best catalyst for the xylan/xylose conversion to furfural. Catalyst structure-activity correlation is thoroughly defined with the help of several physico-chemical properties.
  • Chamundi P Jijil , Siddheshwar N. Bhange , Sreekumar Kurungot And and R. Nandini Devi, Effect of B site coordination environment in the ORR activity in disordered brownmillerites Ba2In2-xCexO5+?, ACS Appl. Mater. Interfaces., Just Accepted Manusript, (2015), DOI:10.1021/am5087837.
    Ba2In2O5 brownmillerites in which In site is progressively doped with Ce exhibit excellent oxygen reduction activity under alkaline conditions. Ce doping leads to structural changes advantageous for the reaction. 25% doping retains the ordered structure of brownmillerite with alternate layers of tetrahedra and octahedra whereas further increase in Ce concentration creates disorder. Structures with disordered oxygen atoms/vacancies are found to be better ORR catalysts probably aided by isotropic ionic conduction and Ba2In0.5Ce1.5O5+? is the most active. This enhanced activity is correlated to the more symmetric Ce site coordination environment in this compound. Stoichiometric perovskite BaCeO3 with the highest concentration of Ce shows very poor activity emphasizing the importance of oxygen vacancies, which facilitate O2 adsorption, in tandem with catalytic sites in oxygen reduction reactions.
  • Anup P. Tathod And Paresh L. Dhepe, Efficient method for the conversion of agricultural waste into sugar alcohols over supported bimetallic catalysts, Bioresour. Technol., 178, 36 - 44 (2015), DOI:10.1016/j.biortech.2014.10.036.
    Promoter effect of Sn in the PtSn/g-Al2O3 (AL) and PtSn/C bimetallic catalysts is studied for the conversion of variety of substrates such as, C5 sugars (xylose, arabinose), C6 sugars (glucose, fructose, galactose), hemicelluloses (xylan, arabinogalactan), inulin and agricultural wastes (bagasse, rice husk, wheat straw) into sugar alcohols (sorbitol, mannitol, xylitol, arabitol, galactitol). In all the reactions, PtSn/AL showed enhanced yields of sugar alcohols by 1.5 to 3 times than Pt/AL. Compared to C, AL supported bimetallic catalysts showed prominent enhancement in the yields of sugar alcohols. Bimetallic catalysts characterized by X-ray diffraction study revealed the stability of catalyst and absence of alloy formation thereby indicating that Pt and Sn are present as individual particles in PtSn/AL. The TEM analysis also confirmed stability of the catalysts and XPS study disclosed formation of electron deficient Sn species which helps in polarizing carbonyl bond to achieve enhanced hydrogenation activity.
  • A. K. Deepa And Paresh L. Dhepe, Lignin depolymerization into aromatic monomers over solid acid catalysts, ACS Catal., 5, 365 - 379 (2015), DOI:10.1021/cs501371q.
    It is imperative to develop an efficient and environmentally benign pathway to valorize profusely available lignin, a component of non-edible lignocellulosic materials into value-added aromatic monomers, which can be used as fuel additives and platform chemicals. To convert lignin, earlier studies used mineral bases (NaOH, CsOH) or supported metal catalysts (Pt, Ru, Pd, Ni on C, SiO2, Al2O3 etc.) under hydrogen atmosphere but these methods face several drawbacks such as corrosion, difficulty in catalyst recovery, sintering of metals, loss of activity etc. Here we show that under inert atmosphere various solid acid catalysts can efficiently convert six different types of lignins in to value-added aromatic monomers. Particularly, SiO2, Al2O3 catalyst gave exceptionally high yields of ca. 60 % for organic solvent soluble extracted products with 95±10 % mass balance in the depolymerization of Dealkaline lignin, Bagasse lignin, ORG and EORG lignins at 250 oC within 30 min. The GC, GC-MS, HPLC, LC-MS, and GPC analysis of organic soluble extracted products confirmed the formation of aromatic monomers with ca. 90 % selectivity. In the products, confirmation of retention of aromatic nature as present in lignin and appearance of several functional groups is done by FT-IR, 1H and 13C NMR studies. Further, isolation of major products by column chromatography was carried out to obtain aromatic monomers in pure form and their further characterization by NMR is presented. Detailed characterization of six different types of lignins obtained from various sources helped in substantiating the catalytic results obtained in these reactions. Meticulous study on fresh and spent catalysts revealed that the amorphous catalysts are preferred to obtain reproducible catalytic results.
  • Babasaheb M. Matsagar And Paresh L. Dhepe, Brönsted acidic ionic liquids catalyzed conversion of hemicellulose into sugars, Catal. Sci. Technol., 5, 531 - 539 (2015), DOI:10.1039/C4CY01047G.
    Development of competent method for the conversion of hemicelluloses, a lignocellulosic component into sugars is essential. In a one-pot method, at 160 °C and in water media, Brönsted acidic ionic liquid (BAIL) catalyzed hydrolysis of hardwood hemicellulose gives 87% yield for C5 sugars (xylose+arabinose). The efficiency of the ILs and acid strength both followed the similar trend, [C3SO3HMIM][HSO4] > [C3SO3HMIM][PTS] > [C3SO3HMIM][Cl] > [BMIM][Cl]. The ion-dipole type interaction present between BAIL and substrate which is proposed by 1H NMR study is suggested to help in achieving better activity with BAIL compared to mineral acid, H2SO4.
  • Holger Braunschweig, Mehmet A. Celik, Rian D. Dewhurst, Magdalena Heid, Florian. Hupp And Sakya S. Sen, Stepwise isolation of low-valent, low-coordinate Sn and Pb mono- and dications in the coordination sphere of platinum, Chem. Sci., 6, 425 - 435 (2015), DOI:10.1039/c4sc02948h.
  • , Applied Surface Science., , (2014), DOI:10.1016/j.apsusc.2014.09.042.
  • Sanjay Singh Negi, Aswathy Thareparambil Venugopalan, Thirumalaiswamy Raja And Anand Pal Singh and Chinnakonda S. Gopinath, A green chemistry approach to styrene from ethylbenzene and air on MnxTi1?xO2 catalyst, RSC Advances., 4, 57087 - 57097 (2014), DOI:10.1039/C4RA11814F.
  • Edwin S. Gnanakumar, Jarpla Madhusudhan Naik, Marimuthu Manikandan And Thirumalaiswamy Raja and Chinnakonda S. Gopinath*, Role of Nanointerfaces in Cu- and Cu+ Au-Based Near- Ambient-Temperature CO Oxidation Catalysts, ChemCatChem., 6, 3116 - 3124 (2014), DOI:10.1002/cctc.201402581.
  • Vaibhav R. Acham, Ankush V. Biradar, Mohan K. Dongare, Erhard Kemnitz And Shubhangi B. Umbarkar , Palladium nanoparticles supported on magnesium hydroxide fluorides: a selective catalyst for olefin hydrogenation, ChemCatChem., 6(11), 3182 - 3191 (2014), DOI:10.1002/cctc.201402469.
  • Swati L. Pandharea, Rajesh R. Jadhaoa, Vedavati G. Puranikb, Pranaya V. Joshib, Frédéric Capetc, Mohan K. Dongarea, Shubhangi B. Umbarkara, Christophe Michonc And Francine Agbossou-Niedercornc, Molybdenum(VI) dioxo complexes for the epoxidation of allylic alcohols and olefins, Journal of Organometallic Chemistry., 772-773, 271 - 279 (2014), DOI:10.1016/j.jorganchem.2014.09.029.
  • Prakash Chandra, Dhananjay S. Doke, Shubhangi B. Umbarkar And Ankush V. Biradar , One-pot synthesis of ultrasmall MoO3 nanoparticles supported on SiO2, TiO2, and ZrO2 nanospheres: an efficient epoxidation catalyst, Journal of Materials Chemistry A., 2, 19060 - 19066 (2014), DOI:10.1039/C4TA03754E.
  • Pavan M. More, Neelam Jagtapa, Atul B. Kulal, Mohan K. Dongare And Shubhangi B. Umbarkar , Magnesia doped Ag/Al2O3 – Sulfur tolerant catalyst for low temperature HC-SCR of NOx, Applied Catalysis B Environmental., 144, 408 - 415 (2014), DOI:10.1016/j.apcatb.2013.07.044.
  • Vidhya C. Ghantani, Mohan K. Dongare And Shubhangi B. Umbarkar , Nonstoichiometric calcium pyrophosphate: A highly efficient and selective catalyst for dehydration of lactic acid to acrylic acid, RSC Advances., 4(63), 33319 - 33326 (2014), DOI:10.1039/C4RA06429A.
  • E. Balaraman* and D. Milstein, Hydrogenation of polar bonds catalysed by ruthenium-pincer complexes, Organomet. Chem., 48, 19 - 44 (2014).
  • S. Das, B. Satpati, H. Chauhan, S. Deka, C. S. Gopinath And T. Bala*, Preferential growth of Au on CdSe quantum dots using Langmuir-Blodgett technique, RSC Advances., , 64535 - 64541 (2014).
  • S. S. Negi, T. V. Aswathy, T. Raja*, A. P. Singh And C. S. Gopinath*, A green chemistry approach to styrene from ethylbenzene and air on MnxTi1-xO2 catalyst, RSC Advances., 4, 64535 - 64541 (2014).
  • S. Raja Ambal, A. K. Yadav, S. N. Jha, D. Bhattacharyya And C. S. Gopinath*, Electronic structure – Sunlight driven water splitting activity correlation of (Zn1-yGay)(O1-zNz), Physical Chemistry Chemical Physics., 16, 23654 - 23662 (2014).
  • E. S. Gnanakumar, Madhusudhan Naik J., M. Manikandan, T. Raja And C. S. Gopinath*, Role of nano-interfaces in Cu and Cu + Au based near ambient temperature CO oxidation catalysts, ChemCatChem., 6, 3116 - 3124 (2014).
  • P. Devaraji, N. K. Sathu And C. S. Gopinath*, Ambient oxidation of benzene to phenol by photocatalysis on Au/Ti0.98V0.02O2 : Role of Holes, ACS Catalysis., 4, 2844 - 2853 (2014).
  • D. Sardar, S. K. Neogi, S. Bandyopadhyay, B. Satpati, R. Jain, C. S. Gopinath And T. Bala*, A facile method for synthesis of Co-core Au-shell nanohybrid, New Journal of Chemistry., 38, 4107 - 4114 (2014).
  • S. Raja Ambal, M. Mapa And C. S. Gopinath* , In1-xGaxN@ZnO: A rationally designed and quantum dot integrated material for water splitting and solar harvesting applications, Dalton Transactions., 43, 12546 - 12554 (2014).
  • J. Kowalska* And C. S. Gopinath, Mapping of copper oxidation state using high pressure photoelectron spectroscopy, Acta Physica Polonica A., 125, 1065 - 1066 (2014).
  • K. Roy, R. Jain And C. S. Gopinath*, Towards A Sustainable and Near Ambient DeNOx Under Lean Burn Conditions: A Revisit to NO Reduction on Virgin and Modified Pd(111) Surfaces, ACS Catalysis., 4, 1801 - 1811 (2014).
  • E. S. Gnanakumar, C. Eswara Rao, S. Kunjir, T.G. Ajithkumar, P. R. Rajamohanan, D. Chakraborty And C. S. Gopinath* , 9-Fluorenemethanol: An Internal Electron Donor to Fine Tune Olefin Polymerization Activity, Dalton Transactions., 14, 9143 - 9151 (2014).
  • K. Roy And C. S. Gopinath*, UV photoelectron spectroscopy at near ambient pressures: Mapping valence band electronic structure changes from Cu to CuO, Analytical Chemistry., 86, 3683 - 3687 (2014).
  • Shelu Garg, Kapil Soni, V.V.D.N. Prasad, Manoj Kumar, T. Bhaskar, J. K. Gupta, G. Murali Dhar* And C. S. Gopinath, Effect of method of preparation on hydrodesulphurization activity of Co- and Ni-promoted MoS2/SBA-15 catalysts, Journal of Chemical Science., 126, 437 - 444 (2014).
  • Sourav Bag, Kanak Roy, C. S. Gopinath And C. Retna Raj* , A Facile Single-Step Synthesis of Nitrogen-Doped Reduced Graphene Oxide - Mn3O4 Hybrid Functional Material for the Electrocatalytic Reduction of Oxygen, ACS Appl. Mater. Interfaces., 6, 2692 - 2699 (2014).
  • N. R. Gupta, B. L. V. Prasad, C. S. Gopinath* And M. V. Badiger*, A Nanocomposite of Silver and Thermo-associating Polymer by Green Route: A Potential Soft-Hard Material for Controlled Drug Release, RSC Advances., 4, 10261 - 10268 (2014).
  • K.S. Thushara, T.G. Ajithkumar, P.R. Rajamohanan* And C. S. Gopinath*, Solid-State NMR Investigations of MgCl2.4(CH3)2CHCH2OH Molecular Adduct: A Peculiar Case of Reversible Equilibrium Between Two Phases, J. Phys. Chem. A., 118, 1213 - 1219 (2014).
  • K. Roy And C. S. Gopinath* , DeNOx at Near Ambient Temperatures and Under Lean Burn Conditions on Modified Pd Surfaces, ChemCatChem., 6, 531 - 537 (2014).
  • K. Sivaranjani, S. Raja Ambal, Tanmay Das, K. Roy, S. Bhattacharyya And C. S. Gopinath*, Disordered Mesoporous TiO2-xNx + Nano Au: An electronically integrated nanocomposite for solar H2 generation, ChemCatChem., 6, 522 - 530 (2014).
  • K.S. Thushara, T.G. Ajithkumar, P.R. Rajamohanan And C.S. Gopinath*, Structural investigations of porous MgCl2-2-butanol molecular adduct as support for olefin polymerization, Applied Catalysis A - General., 469, 267 - 274 (2014).
  • S. Sreedhala, V. SudheeshKumar And C. P. Vinod* , “Structure Sensitive Chemical Reactivity by Palladium Concave Nanocubes and Nanoflowers Synthesised by Seed Mediated Procedure in Aqueous Medium”, Nanoscale., 6, 7496 - 7502 (2014), DOI:10.1039/c4nr01283f.
  • Sourik Mondal, Anupam Samanta, Basab B. Dhar And R. Nandini Devi, Encapsulation of ultra small metal clusters in silica: Evolution of the concept of nanoreactors and the case of Ag–Pd@SiO2 alloy catalyst, Catalysis Today., , (2014), DOI:10.1016/j.cattod.2014.11.006.
    The concept of encapsulation of ultra small clusters within silica evolved as a means to address the sintering of active metal nanoparticles and subsequent deactivation observed in supported noble metal catalysts. It is hypothesised that sintering, which mainly occurs due to mobility of metal species on the support surfaces, can be minimised if the growth and movement of metal nanoparticles are constrained. First, nanoparticles are isolated inside 1D channels in 2D mesoporous compounds and the idea develops to complete encapsulation of thiol protected ultra small nanoclusters in silica spheres. Sintering is better controlled in the latter due to the confined space for growth of nanoparticles. Access of reactant molecules to the active metal surfaces also is ensured by porosity created in the silica matrix forming the basis of the concept of nanoreactors. In this paper, we elaborate on the evolution of this concept from our earlier work on highly sinter resistant silica encapsulated Au, Pd and Au–Pd alloys to the present system of Ag–Pd alloy encapsulated in silica. Silver, with the lowest Tammann temperature among noble metals, is highly prone to sintering which is adequately controlled by alloying with Pd as well as encapsulation in silica. Its enhanced activity in paranitrophenol reduction in comparison with pure metals indicates the advantageous effect of alloying.
  • Thattarathody Rajesh And R. Nandini Devi, Resistance to Ionic Pt Insertion in Oxygen Excess LaMnO3 Perovskite Lattices and Its Effect in Water Gas Shift Reaction, Journal of Molecular Catalysis A: Chemical., 395, 534 - 542 (2014), DOI:10.1016/j.molcata.2014.08.042.
    Pt doped and impregnated LaMnO3 perovskites are synthesized at different temperatures and Pt and Mn states are compared in an attempt to get insight into extent of lattice incorporation of Pt in perovskite. Various characterization studies indicate that oxygen excess system like LaMnO3 presents substantial resistance to B site doping with Pt. This behavior is different from other oxygen deficient perovskites like LaCoO3 and LaFeO3 in which lattice incorporation stabilizes the active species against sintering. Water gas shift reaction was used as a probe reaction to understand the effect of this difference in the activity. In case of LaMnO3, failure in lattice substitution leads to sintering and deactivation at high synthesis temperatures (?700 °C) in both impregnated and doped samples. In doped samples, however, a strong interaction of Pt species with a persistent amorphous phase prevents sintering at lower synthesis temperature thereby enhancing the activity when compared to impregnated sample. The study reveals a possible mechanism in which only Pt(0) species is active with perovskite playing a minimal role in this system due to the resistance to lattice incorporation.
  • Thattarathody Rajesh, Anuj Upadhyay, Anil K. Sinha, Sudip K. Deb And R. Nandini Devi, Effect of Pt incorporation in LaBO3 (B = Mn, Fe, Co) perovskites on Water Gas Shift activity, Journal of Molecular Catalysis A: Chemical., 395, 506 - 513 (2014), DOI:10.1016/j.molcata.2014.09.015.
    Pt incorporated perovskites LaBO3 (B = Mn, Co, Fe) were synthesised and characterised to understand the charge state of Pt in these materials. At the temperature range used in this study, Pt could be stabilised in ionic form in Co and Fe perovskites but not in LaMnO3. Consequent to incorporation of Pt in +2 and +4 oxidation states, reduction in B site ion charge state occurred, enhancing oxygen vacancies. Pt doped Co and Fe perovskites showed high activity for CO conversion under water gas shift conditions but the activity characteristics were found to be different for the two catalysts; LaCo1?xPtxO3?? showed methanation whereas the Fe counterpart was active in water gas shift reaction. It was also observed that methanation could be decreased and water gas shift enhanced in case of Pt doped Co perovskite when compared to Pt impregnated perovskite or mixed oxides.
  • Thattarathody Rajesh and R. Nandini Devi, Pt States in BaCe0.98Pt0.02O3?? During Start Up and Shut Down Operations Under Different Conditions: Stability and Activity of Ionic Pt in Water Gas Shift Reaction, Catalysis Letters., 144, 2227 - 2232 (2014), DOI:10.1007/s10562-014-1378-2.
    Stability of Pt species in doped BaCeO3 perovskites under Water gas shift reaction conditions is studied using X-ray absorption spectroscopy and in situ powder X-ray diffraction. The catalyst BaCe0.98Pt0.02O3–? has Pt in +2 oxidation state and is found to be stable in the ionic form under reaction conditions as well as under various highly reducing shut down and start up conditions. In-situ XRD under Water Gas shift reaction conditions also reveals the Pt ions to be highly stabilized in lattice and no egress is observed.
  • Anup P. Tathod And Paresh L. Dhepe, Towards efficient synthesis of sugar alcohols from mono- and poly-saccharides: Role of metals, supports & promoters, Green Chem., 16, 4944 - 4954 (2014), DOI:10.1039/C4GC01264J.
    Biomass derived sugar alcohols (xylitol, arabitol) find numerous uses in the food, oral and pharmaceutical industries. Their direct synthesis from poly-saccharides however still remains an immense challenge. In this study, we demonstrate in detail, the effects of metals, supports and promoters in enhancing the yields of sugar alcohols from mono- and poly-saccharides. We undertook, synthesis of bimetallic catalysts, M-M’/S (M, Metal=Pt, Ru; M’, Promoter=Sn, Ga, Fe; S, support=g-Al2O3 (AL), SiO2-Al2O3 (SA), Carbon (C)) with varying metal loadings (Pt/Ru=2, 3.5wt%; Sn=0.22, 0.43, 0.87, 1.5, 3.5wt%; Ga/Fe=0.25wt%) by co-impregnation method. The catalytic activities of these catalysts were evaluated in the synthesis of sugar alcohols from xylose (mono-saccharide) and hemicellulose (xylan, poly-saccharide) at 130-190oC. Among all bimetallic catalysts, Pt(3.5)Sn(0.43)/AL catalyst (50%) showed 2.8 times improvement in the sugar alcohols yield compared to monometallic Pt(3.5)/AL catalyst (18%). Similarly, in xylose reaction also 2.4 times enhancement in sugar alcohols yield over Pt(3.5)Sn(0.43)/AL (79%) was observed as against 33% yield obtained with Pt(3.5)/AL. By conducting several experiments it is confirmed that the residual Cl- remained on the catalyst even after calcinations and reductions carried out at 400oC, does not play any role in catalysis. The stability of the Pt(3.5)Sn(0.43)/AL catalyst confirmed by XRD and ICP analysis was responsible in achieving reproducible activity in at least 5 consecutive runs. Formation of electron deficient Sn confirmed by XPS analysis helped polarizing carbonyl group which in turn enhanced the sugar alcohols yields. Formation of PtSn and Pt3Sn species was observed when Sn loading is more than 0.87%.
  • A. K. Deepa And Paresh L. Dhepe, Function of metals and supports on the hydrodeoxygenation of phenolic compounds, ChemPlusChem., 79, 1573 - 1583 (2014), DOI:10.1002/cplu.201402145R1.
    Hydrodeoxygenation (HDO) is an important process to remove oxygen from lignin derived phenolic monomers to obtain chemicals which can be used as fuel or fuel additives. A systematic study is performed to check the effects of supports (acidic, neutral, basic) and noble metals (Pd, Pt, Ru) on HDO of phenol, guaicol and eugenol. When the combinations of metals and supports were evaluated under the similar reaction conditions, it was found that the metals supported on highly acidic support (SiO2-Al2O3) show complete hydrogenation products with a possibility of C-O bond cleavage to achieve a real HDO activity. While on a mildly acidic support (g-Al2O3), complicated product distribution is achieved, neutral (C) and basic (HT) supports gave restricted hydrogenation activity but yielded the products with very high selectivity. Based on the results, reaction pathways are suggested and deliberated. Catalysts showed reproducible activity in recycle runs. Catalysts were characterized by various (XRD, TEM, TPD, ICP-OES) techniques to establish catalyst activity-property relationship.
  • Sakya S. Sen*, A Stable Silanone with a Tri-coordinate Silicon Atom: Century's Wait is Over, Angew. Chem. Int. Ed., 53, 8820 - 8822 (2014), DOI:10.1002/anie.201404793R1.
  • Vishal M. Dhavale, Sachin S. Gaikwad, Leena George And R. Nandini Devi and Sreekumar Kurungot, Nitrogen-doped graphene interpenetrated 3D Ni-nanocages: efficient and stable water-to-dioxygen electrocatalysts, Nanoscale., 6, 13179 - 13187 (2014), DOI:10.1039/C4NR03578J.
  • Thattarathody Rajesh and R. Nandini Devi , Role of Oxygen Vacancies in Water Gas Shift Reaction: Activity Study on BaCe0.98–xYxPt0.02O3?? Perovskites, The Journal Of Physical Chemistry C., 118, 20867 - 20874 (2014), DOI:10.1021/jp503922x.
  • Anupam Samanta And Thattarathody Rajesh and R. Nandini Devi, Confined space synthesis of fully alloyed and sinter resistant AuPd nanoparticles encapsulated in porous silica, Journal of Materials Chemistry A., 2, 4398 - 4405 (2014), DOI:DOI:10.1039/C3TA15194H.
  • Soumya B. Narendranath, Ashok Kumar Yadav, Dibyendu Bhattacharyya, Shambu Nath Jha And and R. Nandini Devi, Photocatalytic H2 Evolution from Water?Methanol System by Anisotropic InFeO3(ZnO)m Oxides without Cocatalyst in Visible Light, ACS Applied Materials and Interfaces., 6, 12321 - 12327 (2014),
  • Prasenjit Bhaumik, Tanushree Kane And Paresh L. Dhepe, Silica and zirconia supported tungsten, molybdenum and gallium oxide catalysts for the synthesis of furfural, Catal. Sci. Technol., 4, 2904 - 2907 (2014), DOI:10.1039/C4CY00530A.
    SiO2 and ZrO2 supported W, Mo and Ga oxide catalysts were prepared by sol-gel and wet-impregnation method. The 10wt% WO3/SiO2 (sol-gel) catalyst showed 61±2% furfural yield from hemicellulose in one-pot fashion at least in 8 cycles. Based on XRD, TPD, Hammett acidity characterizations catalyst structure-activity correlation was drawn.
  • Vysakh A. Bharathan, Govind K Raj, P. A. Joy And C. P. Vinod*, “Synthesis and Reactivity of Magnetically Diverse Au@Ni Core-shell Nanostructures”, Particle & Particle Systems Characterization., 31, 236 - 244 (2014), DOI:10.1002/ppsc.201300195.
  • Prasenjit Bhaumik And Paresh L. Dhepe, Exceptionally high yields of furfural from assorted raw biomass over solid acids, RSC Adv., 4, 26215 - 26221 (2014), DOI:10.1039/C4RA04119D.
    Development of stable and recyclable solid acid catalysts in the efficient valorisation of hemicellulose to yield C5 sugars and furfural is vital to boost the prospects of using lignocelluloses for the chemicals synthesis. Using SAPO-44 catalyst an environmentally benign process of furfural synthesis from diversified real substrates (without any treatment & the need for separation of its components) is shown. In an efficient one-pot methodology, at 443 K and in the presence of biphasic solvent system, selective conversions of hemicelluloses from raw biomass (bagasse, rice husk & wheat straw) to extraordinarily high yields of furfural of about 93% were attainable. Under similar reaction conditions, 82% yield of furfural is also achievable directly from isolated hemicellulose within 10 h. Hydrophilic SAPO-44 having higher hydrothermal stability showed similar activity for all the substrates minimum up to 8 times in recycle runs. Various physico-chemical characterizations (XRD, TGA-DTG, TPD-NH3, solid state NMR) of fresh and spent catalysts edify on the SAPO-44 stability.
  • Paresh L. Dhepe , Ashutosh Kelkar, Babasaheb Matsagar And Sandip Singh, Acidic ionic liquids catalyzed depolymerization of lignin, Patent., IN, (2014).
  • Paresh L. Dhepe And Anup Tathod, Production of sugar alcohols, xylitol and arabbitol using bimetallic supported metal catalysts, Patent., IN, (2014).
  • Paresh L. Dhepe And Babasaheb Matsagar, Conversion of hemicellulose using acidic ionic liquids, Patent., IN, (2014).
    Patent applied on a process for acidic ionic liquid catalyzed hemicellulose conversion
  • Prasenjit Bhaumik, A. K. Deepa, Tanushree Kane And Paresh L. Dhepe, Value addition to lignocellulosics and biomass-derived sugars: An insight into solid acid-based catalytic methods, J. Chem. Sci., 126, 373 - 385 (2014), DOI:10.1007/s12039-014-0574-3.
    For the synthesis of important platform chemicals such as sugars (xylose and arabinose) and furans (furfural and 5-hydroxymethylfurfural (HMF)) from carbohydrates (hemicellulose and fructose) solid acid catalysts are employed. Similarly, over solid acid catalysts, conversion of lignin into aromatic monomers is performed. It is observed that in the dehydration of fructose, because of higher hydrothermal stability, silicoaluminophosphate (SAPO) catalysts give better activity (78% HMF yield) compared with other solid acid catalysts (<63% HMF yield) at 175°C. Particularly, SAPO-44 catalyst can be reused at least 5 times with marginal decrease in the activity. Zeolite, HUSY (Si/Al = 15) is active in the conversion of isolated (pure) hemicellulose to produce 41% C5 sugars in water. The catalyst is also active in the selective conversion of hemicellulose from bagasse to yield 59% C5 sugars. It is possible to obtain high yields of furfural (54%) directly from bagasse if instead of water, water+toluene solvent system is used. Depolymerization of lignin using HUSY catalyst produced aromatic monomers with 60% yield at 250°C. A detailed catalyst characterization study is performed to understand the correlation between catalyst activity and morphology. To understand the effect of impurities present in the substrate over solid acid catalysts, metal-exchange study is carried out.
  • A. K. Deepa And Paresh L. Dhepe, Solid acid catalyzed depolymerization of lignin into value added aromatic monomers, RSC Adv., 4, 12625 - 12629 (2014), DOI:10.1039/C3RA47818A.
    Depolymerization of lignin to produce value-added aromatic monomers has attracted a lot of attention since these monomers can potentially be used as fuel additives (octane enhancers) and in turn can improve the prospects of cellulosic ethanol technology to become economically feasible. Here we show that solid acid catalysts could efficiently convert lignin into value added aromatic monomers with 60% yields and ca. 95% mass balance when depolymerization reactions were carried out at 250°C for 30–120 minutes. We found that the reaction parameters have a remarkable effect on improving the yields.
  • Ramakanta Sahu And Paresh L. Dhepe, Synthesis of 2,5-furandicarboxylic acid by the aerobic oxidation of 5-hydroxymethyl furfural over supported metal catalysts, Reac. Kinet. Mech. Cat., 112, 173 - 187 (2014), DOI:10.1007/s11144-014-0689-z.
    Supported Pt catalysts are synthesized, characterized and are used in the liquid phase air oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA). Under the optimum reaction conditions of a stepwise increase in the reaction temperature (75 and 140°C for 12 h each), we achieved as high as 96% FDCA yield in presence of 1 bar oxygen pressure over Pt/g-Al2O3. It is shown that as the oxygen pressure increases (1–10 bar), the FDCA yields decrease, since at higher partial pressure of oxygen, overoxidation reactions of substrate and product(s) are possible. It is interesting to note that even with air as an oxidant, we obtained similar yields of FDCA as that with oxygen. Moreover, the effects of base (weak or strong), its concentration (equimolar or excess) were studied in detail. It is important to increase the reaction temperature in a stepwise manner to achieve higher yields of FDCA since at higher temperatures HMF undergoes self-degradation and thus the yields of FDCA decrease. The self-degradation of HMF is also proved by undertaking the reaction under nitrogen environment. The study on the effect of substrate/catalyst ratio is done to improve up on the economics of overall process. The effect of supports (reducible and non-reducible) and their oxygen storage capacity is discussed and is proposed to be one of the factors to change the course of reaction. Furthermore, we have shown that FDCA formed in the reaction can be successfully isolated (91%, isolated yield) in the pure form and its purity is confirmed by NMR, melting point, and elemental analysis. The catalysts were characterized with X-ray powder diffraction, transmission electron microscopy and inductively coupled plasma-optical emission spectroscopy techniques.
  • Johannes Brand, Holger Braunschweig And Sakya S. Sen, B=B and B?E (E=O and N) Multiple Bonds in the Coordination Sphere of Late Transition Metals, Acc. Chem. Res., 47, 180 - 191 (2014), DOI:10.1021/ar400106u.
  • Johannes Brand, Holger Braunschweig, Florian Hupp, Ashwini K. Phukan, Krzysztof Radacki And Sakya S. Sen, A B–C Double Bond Unit Coordinated to Platinum: An Alkylideneboryl Ligand that is Isoelectronic to Neutral Aminoborylene Ligands, Angew. Chem. Int. Ed., 53, 2240 - 2244 (2014), DOI:10.1002/anie.201310557.
  • Soumya B. Narendranath, Ashok Kumar Yadav, T.G. Ajithkumar, Dibyendu Bhattacharyya, Shambhu Nath Jha, Krishna K. Dey, Thirumalaiswamy Raja And R. Nandini Devi , Investigations into variations in local cationic environment in layered oxide series InGaO3(ZnO)m (m = 1-4), Dalton Transactions., 43 (5), 2120 - 2126 (2014).
  • D.-L. Nguyen, S. Umbarkar, M. K. Dongare, C. Lancelot, J.-S. Girardon, C. Dujardin And P. Granger, Promising stability of gold-based catalysts prepared by direct anionic exchange for DeNO x applications in lean burn conditions, Topics in Catalysis., 56(1-8), 157 - 164 (2013), DOI:10.1007/s11244-013-9946-z.
  • Prakash Chandra, Swati L Pandhare, Shubhangi B Umbarkar, Mohan K Dongare And Kumar Vanka, Mechanistic studies on the roles of the oxidant and hydrogen bonding in determining the selectivity in alkene oxidation in the presence of molybdenum catalysts, Chemistry - A European Journal., 19(6), 2030 - 2040 (2013), DOI:10.1002/chem.201202597.
  • Vaibhav R. Acham, Mohan K. Dongare And Shubhangi B. Umbarkar, MOO2Cl2·2DMSO: recyclable catalyst for selective oxidation of alcohols under solvent free conditions, Current Catalysis., 2(3), 237 - 243 (2013).
  • Swati L. Pandhare, Trupti V. Kotbagi, Mohan K. Dongare And Shubhangi B. Umbarkar, Copper-exchanged SiO2/Al2O3 prepared by sol-gel method for intermolecular hydroamination of terminal alkynes, Current Catalysis., 2(1), 62 - 69 (2013), DOI:10.2174/2211544711302010010.
  • Trupti V. Kotbagi, Ankush V. Biradar, Shubhangi B. Umbarkar And Mohan K. Dongare, Isolation, characterization, and identification of catalytically active species in the MoO3/SiO2 catalyst during solid acid catalyzed reactions, ChemCatChem., 5(6), 1531 - 1537 (2013), DOI:10.1002/cctc.201200662.
  • Vidhya C. Ghantani, Samadhan T. Lomate, Mohan K. Dongare And Shubhangi B. Umbarkar, Catalytic dehydration of lactic acid to acrylic acid using calcium hydroxyapatite catalysts, Green Chemistry., 15(5), 1211 - 1217 (2013), DOI:10.1039/C3GC40144H.
  • V. Subramanian, E. S. Gnanakumar, D-W. Jeong, W-B. Han, C. S. Gopinath* And H-S. Roh*, Rationally Designed CuFe2O4-Mesoporous Al2O3 Nanocomposite Towards Stable Performance for High Temperature Water-Gas Shift Reaction, Chemical Communications (Cover page article)., 49, 11257 - 11259 (2013).
  • M. Mapa, S. RajaAmbal And C. S. Gopinath*, ZnO-based Solid Solutions for Visible Light Driven Photocatalysis, Transactions of the Materials Research Society of Japan., 38, 145 - 158 (2013).
  • A. Pandikumar, K. Sivaranjani, C. S. Gopinath And R. Ramaraj*, Aminosilicate Sol-Gel Stabilized N-Doped TiO2 – Au Nanocomposite Materials and their Potential Environmental Remediation Applications, RSC Advances., 3, 13390 - 13398 (2013).
  • A. Indra, C. S. Gopinath, S. Bhaduri* And G. K. Lahiri* , Hydroxyapatite supported palladium catalysts for Suzuki-Miyaura cross-coupling reaction in aqueous medium, Catalysis Science and Technology., 3, 1625 - 1633 (2013).
  • S. B. Waghmode*, S. S. Arbuj, B. N. Wani And C.S. Gopinath, Palladium chloride catalyzed photochemical Heck reaction, Canadian J. Chemistry., 91, 348 - 351 (2013).
  • A. C. Sunil Sekhar, C. J. Meera, K. V. Ziyad, C. S. Gopinath And C. P. Vinod*, Synthesis and catalytic activity of mono disperse gold-mesoporous silica core shell nanocatalysts, Catalysis Science and Technology., 3, 1190 - 1193 (2013).
  • Edwin S. Gnanakumar, Jino John, T. Raja And C. S. Gopinath* , Functional and Disordered Meso-Macroporous gama–Al2-xMxO3±y (M = Cu and/or Ce), J. Nanoscience and Nanotechnology, (Invited Paper for special issue on Nano architectonics of porous materials)., 13, 2682 - 2688 (2013).
  • E. S. Gnanakumar, R. R. Gowda, S. Kunjir, T.G. Ajithkumar, P. R. Rajamohanan, D. Chakraborty And C. S. Gopinath*, MgCl2.6CH3OH: A Simple Molecular adduct and its influence as Porous Support for Olefin Polymerization, ACS Catalysis., 3, 303 - 311 (2013).
  • K. Roy, C.P. Vinod* And C. S. Gopinath*, Design and Performance Aspects of a Custom Built Ambient Pressure Photoelectron Spectrometer Towards Bridging the Pressure Gap: Oxidation of Cu, Ag and Au Surfaces at 1 mbar O2 pressure, J. Physical Chemistry C., 117, 4717 - 4726 (2013).
  • Sanjay S. Negi, K. Sivaranjani, A. P. Singh And C. S. Gopinath*, Disordered mesoporous V/TiO2 system for ambient oxidation of sulfides to sulfoxides, Applied Catalysis A - General., 452, 132 - 138 (2013).
  • Roy, Kanak; Vinod, C. P* And Gopinath Chinnakonda S*, "Design and Performance Aspects of a Custom-Built Ambient Pressure Photoelectron Spectrometer toward Bridging the Pressure Gap: Oxidation of Cu, Ag, and Au Surfaces at 1 mbar O-2 Pressure”, J. Phys. Chem C., 117, 4717 (2013).
  • C. P. Vinod, “Insights into heterogeneous catalysis through surface science techniques”, NEW AND FUTURE DEVELOPMENTS IN CATALYSIS: CATALYSIS BY NANOPARTICLES (Elsevier)., Chapter 12, 289 - 304 (2013), DOI:10.1016/B978-0-444-53874-1.00012-3.
  • Prasenjit Bhaumik And Paresh L. Dhepe, Influence of properties of SAPO's on the one-pot conversion of mono-, di- and poly-saccharides into 5-hydroxymethylfurfural, RSC Adv., 3, 17156 - 17165 (2013), DOI:10.1039/C3RA43197E.
    Synthesis of 5-hydroxymethylfurfural (5-HMF) from biomass derived mono- and poly-saccharides is gaining importance because of its usefulness in the preparation of important chemicals. In our work, we have synthesized several silicoaluminophosphate (SAPO) catalysts, and have shown that in the absence of any other pH modifying reagents, those are active in converting mono- and poly-saccharides into 5-HMF under biphasic reaction condition at 175°C. Particularly, SAPO-44 catalyst showed the best activity in the conversion of fructose to yield 78% 5-HMF with 88% selectivity. On the contrary, all other catalysts showed lower yields (H-MOR: 63%, SAPO-5: 32%, 2DCT: 60%). Over SAPO-44, good yields for 5-HMF were observed when glucose (67%), maltose (57%), cellobiose (56%) and starch (68%) were used as substrates. Recycle study carried out with SAPO-44 catalyst in the fructose conversion reaction showed marginal decrease in the activity up to 3rd run and then afterwards constant activity was observed up to 5th run (1st: 78%, 2nd: 71%, 3rd: 66%, 4th: 65%, 5th: 65%). Catalyst characterizations revealed that SAPO catalysts have higher hydrophilic nature than H-MOR (Si/Al = 10) and hence it is postulated that this property may help in achieving better results. Further studies on the catalyst characterizations revealed that SAPO-44 undergoes modifications in its structure. However, ICP-OES data suggests that Al and/or P are not leached out in the solution indicating that change in local environment around elements is possible. The influence of acid amount, type of acid site etc. on the catalytic activity is discussed and found out that strong acid sites are required to boost the 5-HMF yields.
  • Prasenjit Bhaumik And Paresh L. Dhepe, Efficient, stable, and reusable silicoaluminophosphate for the one-pot production of furfural from hemicellulose, ACS Catal., 3, 2299 - 2303 (2013), DOI:10.1021/cs400495j.
    Development of stable, reusable, and water-tolerant solid acid catalysts in the conversion of polysaccharides to give value-added chemicals is vital because catalysts are prone to undergo morphological changes during the reactions. With the anticipation that silicoaluminophosphate (SAPO) catalysts will have higher hydrothermal stability, those were synthesized, characterized, and employed in a one-pot conversion of hemicellulose. SAPO-44 catalyst at 170°C within 8 h could give 63% furfural yield with 88% mass balance and showed similar activity up to at least 8 catalytic cycles. The morphological studies revealed that SAPO catalysts having hydrophilic characteristics are stable under reaction conditions.
  • Anup Tathod, Tanushree Kane, E. S. Sanil And Paresh L. Dhepe, Solid base supported metal catalysts for the oxidation and hydrogenation of sugars, J. Mol. Catal. A: Chem., 388-389, 90 - 99 (2013), DOI:10.1016/j.molcata.2013.09.014.
    Pt impregnated on g-Al2O3 (acidic support) and hydrotalcite (basic support) catalysts were synthesized, characterized and used in the oxidation and hydrogenation reactions of C5 and C6 sugars. In the absence of homogeneous base, 83% yield for gluconic acid; an oxidation product of glucose can be achieved over Pt/hydrotalcite (HT) catalyst at 50°C under atmospheric oxygen pressure. Similarly, 57% yield for xylonic acid, an oxidation product of xylose is also possible over Pt/HT catalyst. Hydrogenation of glucose conducted using Pt/g-Al2O3 + HT catalytic system showed 68% sugar alcohols (sorbitol + mannitol) formation. The 82% yield for C5 sugar alcohols (xylitol + arabitol) was obtained by subjecting xylose to hydrogenation over Pt/g-Al2O3 + HT at 60°C. UV analysis helped to establish the fact that under alkaline conditions sugars prefer to remain in open chain form in the solution and thus exposes single -CHO group which further undergoes oxidation and hydrogenation reactions to yield acids and alcohols.
  • Thomas Arnold, Holger Braunschweig, J. Oscar, C. Jimenez-Halla, Kryzsztof Radacki And Sakya S. Sen, Simultaneous Fragmentation and Activation of White Phosphorus, Chem. Eur. J., 19, 9114 - 9117 (2013).
  • Thomas Arnold, Holger Braunschweig, Florian Hupp, Kryzsztof Radacki And Sakya S. Sen, Reactions of a [1],[1]Disilamolybdenocenophane towards Unsaturated Compounds, Eur. J. Inorg. Chem., , 5027 - 5032 (2013).
  • Ruchira Mukherji, Anupam Samanta, Rajith Illathvalappil, Somak Chowdhury, Asmita Prabhune And R. Nandini Devi, Selective imaging of quorum sensing receptors in bacteria using fluorescent Au nanocluster probes surface functionalised with signal molecules, ACS Applied Materials and Interfaces., 5 (24), 13076 - 13081 (2013), DOI:10.1021/am404093m.
  • Anupam Samanta And R. Nandini Devi, Pd ultra small clusters as precursors for silica encapsulated Pd nanoreactors: highly sinter resistant catalysts, ChemCatChem., 5, 1911 - 1916 (2013).
  • Ashok Kumar Venugopal, Aswathy Thareparambil Venugopalan And Periyasamy Kaliyappan and Thirumalaiswamy Raja* , Oxidative dehydrogenation of ethyl benzene to styrene over hydrotalcite derived cerium containing mixed metal oxides, Green Chemistry., 15, 3259 - 3267 (2013), DOI:DOI: 10.1039/C3GC41321G.
  • Dipankar Srimani, Ekambaram Balaraman, Peng Hu, Yehoshoa Ben-David And David Milstein*, Formation of Tertiary Amides and H2 by Dehydrogenative Coupling of Primary Alcohols with Secondary Amines Catalyzed by Ruthenium Bipyridine-Based Pincer Complexes, Adv. Syn. Catal., DOI:10.1002/adsc.201300620, (2013).
  • Rigoberto Barrios-Francisco, Ekambaram Balaraman, Yael Diskin-Posner, Gregory Leitus, Linda J. W. Shimon And David Milstein*, PNN-Ru Pincer Complexes Based on Phosphinated 2,2’-Dipyridinemethane- and 2,2’-Oxobispyridine. Metal-ligand Cooperation in Cyclometallation and Catalysis, Organometallics., 32, 2973 - 2982 (2013).
  • Robert Langer, Ido Fuchs, Matthias Vogt, Ekambaram Balaraman, Yael Diskin-Posner, Linda J. W. Shimon, Yehoshoa Ben-David And David Milstein*, Stepwise Metal-Ligand Cooperation via a Reversible Aromatization-Deconjugation-Sequence in Ruthenium Complexes with a Tetradentate Phenanthroline-based Ligand, Chem. Eur. J., 19, 3407 - 3414 (2013).
    Highlight: Selected as VIP article by Chem. Euro. J.
  • Thomas Zell, Robert Langer, Mark A. Iron, Leonid Konstantinovski, Linda J. W. Shimon, Yael Diskin-Posner, Gregory Leitus, Ekambaram Balaraman, Yehoshoa Ben-David And David Milstein*, Synthesis, Structures, and Dearomatization by Deprotonation of Iron Complexes Featuring Bipyridine-based PNN Pincer Ligands, Inorg. Chem., 52, 9636 - 9649 (2013).
  • Ekambaram Balaraman, Eugene Khaskin, Gregory Leitus And David Milstein*, Catalytic Transformation of Alcohols to Carboxylic Acid Salts and H2 Using Water as the Oxygen Atom Source, Nature. Chem., 5, 122 - 125 (2013).
    Highlights: • RSC Chemistryworld • CORANTE - In the Pipeline • The Chemistry Cascade
  • A. C. Sunil Sekhar, C. J. Meera, K. V. Ziyad, Chinnakonda. S. Gopinath And C. P. Vinod*, "Synthesis and catalytic activity of monodisperse gold–mesoporous silica core–shell nanocatalysts”, Catal. Sci. Technol., 3, 1190 (2013).
  • , Micro & Nano Letters., , (2012), DOI:10.1049/mnl.2011.0498.
  • T. Kotbagi, D. L. Nguyen, C. Lancelot, C. Lamonier, K-A. Thavornprasert, Z. Wenli, M. Capron, L. Jalowiecki-Duhamel, S. Umbarkar, M. Dongare And F. Dumeigni , Transesterification of diethyl oxalate with phenol over Sol-Gel MoO3/TiO2 catalysts, ChemSusChem., 5(8), 1467 - 1473 (2012), DOI:10.1002/cssc.201100802.
  • D. L. Nguyen, S. Gillot, D. O. Souza, P. Blanchard, C. Lamonier, E. Berrier, T. V. Kotbagi, M. K. Dongare, S. B. Umbarkar, S. Cristol, E. Payen And C. Lancelot, One-pot sol-gel preparation for efficient cobalt-molybdenum-TiO2 hydrotreating catalysts, ChemCatChem., 4(12), 2112 (2012), DOI:10.1002/cctc.201200165.
  • Lu?n Nguy?n Duy, S. Umbarkar, M. K. Dongare, C. Lancelot, J.-S. Girardon, C. Dujardin And P. Granger, Deposition–precipitation versus anionic-exchange Au/Al 2 O 3 catalysts: A comparative investigation towards the selective reduction of NO x, Catalysis Communications., 26, 225 - 230 (2012), DOI:10.1016/j.catcom.2012.06.004.
  • Macchindra G. Chandgude, Ankush V. Biradar, Trupti V. Kotbagi, Vedavati G. Puranik, Mohan K. Dongare And Shubhangi B. Umbarkar , Selective oxidation of nonrefractory and refractory sulfides by cyclopentadienyl molybdenum acetylide complexes as efficient catalysts, Catalysis Letters., 142(11), 1352 - 1360 (2012), DOI:10.1007/s10562-012-0898-x.
  • Edwin S. Gnanakumar, K. S. Thushara, R. R. Gowda, S. K. Raman, T. G. Ajithkumar, P. R. Rajamohanan, D. Chakraborty And C. S. Gopinath* , MgCl2.6C6H11OH: A High Mileage Porous Support for Ziegler-Natta Catalyst, J. Physical Chemistry C., 116, 24115 - 24122 (2012).
  • A. C. Sunilsekhar, K. Sivaranjani, C. S. Gopinath* And C. P. Vinod* , A simple one pot synthesis of nano gold – mesoporous silica and its oxidation catalysis, Catalysis Today (Invited – Dr. P. Ratnasamy’s Festschrift on his 70th Birthday)., 198, 92 - 97 (2012).
  • K. S. Thushara, E. S. Gnanakumar, R. Mathew, T. G. Ajithkumar, P. R. Rajamohanan, S. Bhaduri* And C. S. Gopinath*, MgCl2.4((CH3)2CHCH2OH): A New Molecular Adduct for the preparation of TiClx/MgCl2 Catalyst for Olefin Polymerization, Dalton Transactions., 41, 11311 - 11318 (2012).
  • T. Mathew, S. Kumarsrinivasan, E. S. Gnanakumar, Y. Yamada*, T. Kobayashi And C. S. Gopinath*, gama-Al2-xMxO3?y (M = Ti4+ through Ga3+): Potential Pseudo-3D Mesoporous Material with Tunable Acidity and Electronic Structure, Journal of Materials Chemistry (Cover page article)., 22, 13484 - 13493 (2012).
  • T. Rajesh, A. K. Rajarajan, C. S. Gopinath And R. Nandini Devi*, Evidence of cationic Pt active for Water Gas Shift reaction: Pt doped BaCeO3 perovskite, J. Physical Chemistry C., 116, 9526 - 9532 (2012).
  • S. Kumarsrinivasan, A. Verma And C.S. Gopinath*, Molecular oxygen assisted oxidative dehydrogenation of ethyl benzene to styrene with nanocrystalline Ti1-xVxO2, Green Chemistry., 14, 461 - 471 (2012).
  • S. Kumarsrinivasan, S. Agarkar, S. B. Ogale* And C. S. Gopinath* , Toward a quantitative correlation between microstructure and DSSC efficiency: A case study of TiO2-xNx nanoparticles in a disordered mesoporous framework, J. Physical Chemistry C., 116, 2581 - 2587 (2012).
  • Paresh L. Dhepe And Deepa A. K, Depolymerization of lignin over solid acid catalysts, Patent., US20120302796 A1, BR, ES, IN, (2012).
    Patent applied on lignin depolymerization over solid acid catalysts
  • Wenhao Fang, Cyril Pirez, MickaelCapron, Sebastien Paul, Thirumalaiswamy Raja, Wenhao Fang, Paresh L. Dhepe, Franck Dumeignilabe And Louise Jalowiecki-Duhamel, Ce-Ni mixed oxide as efficient catalyst for H2 production and nanofibrous carbon material from ethanol in the presence of water, RSC Adv., 2, 9626 - 9634 (2012), DOI:10.1039/C2RA21701E.
    Hydrogen production from ethanol steam reforming(H2O/C2H5OH = 3) was studied over Ce–Ni based catalysts issued from different preparation methods (co-precipitation (CP), impregnation (IMP) and incipient wetness impregnation (IWI)). Catalysts prepared by the CP method exhibit higher activity and much better stability compared to the other two types of catalysts. The Ni1CeOY–CP catalyst is able to completely convert ethanol at 450°C to H2, CO2 and CH4 (almost no CO is observed), with a H2 yield of 3 moles of hydrogen produced per mole of ethanol converted. A very high H2 yield of 4.6 mol molEtOH?1 is achieved over the Ni1CeOY–CP mixed oxide at 650 °C. Correlations between the preparation method, catalytic activity and stability, and type of carbon deposition are discussed. The CP method forms very active small sized NiO (15 nm) and CeO2 (4 nm) nanoparticles, leading to the formation of a lower amount of carbon deposition in the form of nanofibrous carbon materials, the size of which depends on the Ni related nanoparticles. For CP catalysts, the graphitic filaments obtained correspond to carbon nanofibers (CNFs) and carbon nanotubes (CNTs) with a much smaller and homogenous size compared to the filamentous carbon formed over the catalysts issued from the other preparation methods, in relation to the active particles size. The catalytic stability is attributed to the type of carbon formed.
  • Paresh L. Dhepe And Ramakanta Sahu, A one-pot method for the selective conversion of hemicellulose from crop waste into C5 sugars and furfural by using solid acid catalysts, ChemSusChem., 5, 751 - 761 (2012), DOI:10.1002/cssc.201100448.
    We present a solid-acid catalyzed one-pot method for the selective conversion of solid hemicellulose without its separation from other lignocellulosic components, such as cellulose and lignin. The reactions were carried out in aqueous and biphasic media to yield xylose, arabinose, and furfural. To overcome the drawbacks posed by mineral acid methods in converting hemicelllulose, we used heterogeneous catalysts that work at neutral pH. In a batch reactor, these heterogeneous catalysts, such as solid acids (zeolites, clays, metal oxides etc.), resulted in >90% conversion of hemicellulose. It has been shown that the selectivity for the products can be tuned by changing the reaction conditions, for example, a reaction carried out in water at 170°C for 1h with HBeta (Si/Al=19) and HUSY (Si/Al=15) catalysts gave yields of 62 and 56% for xylose and arabinose, respectively. With increased reaction time (6h) and in presence of only water, HUSY resulted in yields of 30% xylose+arabinose and 18% furfural. However, in a biphasic reaction system (water+p-xylene, 170°C, 6h) yields of 56% furfural with 17% xylose+arabinose could be achieved. It was shown that with the addition of organic solvent the furfural yield could be increased from 18 to 56%. Under optimized reaction conditions, >90% carbon balance was observed. The study revealed that catalysts were recyclable with a 20% drop in activity for each subsequent run. It was observed that temperature, pressure, reaction time, substrate to catalyst ratio, solvent, and so forth had an effect on product formation. The catalysts were characterized by means of X-ray diffraction, temperature-programmed desorption of NH3, inductively coupled plasma spectroscopy, elemental analysis, and solid-state NMR (29Si, 27Al) spectroscopy techniques.
  • Sakya S. Sen, Jakob Hey, Daniel Kratzert, Herbert W. Roesky And Dietmar Stalke, A Remarkable End-on Activation of Diazoalkane and Cleavage of Both C-Cl bonds of Dichloromethane with a Silylene to a Single Product with Five-Coordinate Silicon Atoms, Organometallics., 31, 435 - 439 (2012).
  • Sakya S. Sen, Shabana Khan, Prinson P. Samuel And Herbert W. Roesky, Chemistry of functionalized silylenes, Chem. Sci., 2, 659 - 682 (2012).
  • Sakya S. Sen, Shabana Khan And Selvarajan Nagendran and Herbert W. Roesky , Inter-connected Bis-silylene: A New Dimension in Silicon Chemistry, Acc. Chem. Res., 45, 578 - 587 (2012).
  • Shabana Khan, Sakya S. Sen And Herbert W. Roesky, Activation of phosphorus by compounds with group 14 elements in low oxidation states, Chem. Commun., 48, 2169 - 2179 (2012).
  • Prinson P. Samuel, Ramachandran Azhakar, Rajendra S. Ghadwal, Sakya S. Sen, Herbert W. Roesky, Markus Granitzka, Julia Matussek, Regine Herbst-Irmer And Dietmar Stalke, Stable Silaimines with Three- and Four-Coordinate Silicon Atoms, Inorg. Chem., 51, 11049 - 11054 (2012).
  • Nagesh B Kolhe, R Nandini Devi, Satyaprasad P Senanayak, B Jancy And K S Narayan and S K Asha, Structure Engineering of Naphthalenediimides for improved Charge Carrier Mobility: Self-assembly by Hydrogen Bonding, Good or Bad?, Journal of Materials Chemistry., 22, 15235 - 15246 (2012).
  • Anupam Samanta And Basab B. Dhar and R. Nandini Devi, Novel porous silica encapsulated Au nanoreactors as peroxidase mimic for one pot glucose detection, New Journal of Chemistry., 36, 2625 - 2629 (2012).
  • Atul K. Prashar, S. Mayadevi And R. Nandini Devi, Effect of particle size on selective hydrogenation of cinnamaldehyde by Pt encapsulated in mesoporous silica, Catalysis Communications., 28, 42 - 46 (2012).
  • Sumona Ghosh, Chamundi P. Jijil And R. Nandini Devi, In situ encapsulation of ultra small ceria nanoparticles stable at high temperatures in the channels of mesoporous silica, Microporous Mesoporous Materials., 155, 215 - 219 (2012).
  • Anupam Samanta, Basab B. Dhar And R. Nandini Devi, Ultrasmall Gold Cluster Arrays Encapsulated in Silica Nanospheres: Applications in Fluorescence Imaging and Catalysis, Journal of Physical Chemistry C., 116, 1748 - 1754 (2012).
  • Thattarathody Rajesh, Anakot K. Rajarajan, Chinnakonda S. Gopinath And R. Nandini Devi, Evidence of Cationic Pt Active for Water Gas Shift Reaction: Pt-Doped BaCeO3 Perovskite, Journal of Physical Chemistry C., 116 (17), 9526 - 9532 (2012).
  • Chamundi Jijil, Sreekuttan Unni, Kurungot Sreekumar And R. Nandini Devi, Disordered brownmillerite Ba2InCeO5+ with enhanced oxygen reduction activity, Chemistry of Materials., 24 (14), 2823 - 2828 (2012).