NFNO: 0104NF2025/IN

IF: 8.067 (2021) & 5.7 (2023) Lead-free perovskite nanocrystals (NCs) have attracted considerable attention due to their excellent optoelectronic properties. However, they generally exhibit broadband emission with poor color purity. Similarly, obtaining tunable red/green/blue (RGB) emissions from lead-free perovskite NCs is highly desirable for several display applications. However, directly synthesizing lead-free perovskite NCs with tunable RGB emission and high color purity remains challenging. Herein, we have developed a simple and rapid microwave-assisted (MW-AT) synthesis strategy for synthesizing Mn-doped CsBr [Mn2+:CsBr] to phase engineering of non-toxic and stable all-inorganic cesium manganese bromide perovskite NCs in a nonpolar solvent with tunable blue-green-red emission color with high color purity. The phase transition was triggered by changing the MnBr2 concentration during the microwave synthesis: from Mn2+:CsBr (blue emission) to zero dimensional (0D) Cs3MnBr5 NCs (green emission) to one dimensional (1D) CsMnBr3 NCs (red emission). In addition, in a controlled moisture environment, both the 0D Cs3MnBr5 and 1D CsMnBr3 NCs were transformed into 0D Cs2MnBr4·2H2O NCs (blue emission), which could be inversely transformed back to their respective original phase via thermal annealing. Thus, our work highlights for the first time a rapid and efficient MW-AT synthesis strategy to obtain phase-pure tunable optical properties with high color purity from Mn-doped CsBr to cesium manganese bromide perovskite NCs via phase engineering, which can be further utilized in designing anti-counterfeiting and encryption materials for coding with high security and information concealment. Our work also provides a new avenue for exploring efficient MW-AT synthesis of other earth-abundant eco-friendly highly luminescent Pb-free perovskite NCs for future endeavors.

DSSC device with high open-circuit potential of 860 mV with iodolyte electrolyte

Invited Feature Article

Equal Contribution from the first two authors

The feature article published in ChemComm highlights the recent progress in the field of polymer electrolytes for supercapacitors and zinc ion/zinc air batteries (ZIBs and ZABs). This article comprehensively examines the evolution, recent developments, and future directions in the polymer electrolytes, with a focus on their application in cutting-edge energy storage systems such as ZIBs, ZABs, and supercapacitors.

IF: 8.8; Electrocatalytic water splitting to hydrogen and oxygen is considered to be one of the significant routes for future renewable energy conversion. Therefore, the development of unique, efficient, and cost-effective bifunctional electrocatalysts, which can perform both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), is critical for the accessible utilization of renewable energy. The increasing overall efficiency of the water-splitting reaction is pivotal for sustainable energy conversion and hydrogen production. Herein, we present a facile solution-based synthesis route to control the crystallinity of the cobalt tungstate (CoWO4) nanomaterials to amorphous, semiamorphous, and crystalline phases and further exploit these nanomaterials as bifunctional electrocatalysts for the HER, OER, and overall electrochemical water splitting reaction. Notably, the semiamorphous cobalt tungstate nanomaterials show a remarkable surface area of approximately 150 m2/g, the highest reported for CoWO4-based materials, and demonstrated superior activity for both the OER and HER and outstanding stability over the amorphous and crystalline counterparts. Notably, the SemiAmp||SemiAmp electrolyzer demonstrated a better performance for overall water splitting than the commercial RuO2||Pt/C electrolyzer.

Our this paper in SMALL illustrates how the modulation of the electronic d-band center, structural defects (line defects), and particle size of Pt3Co alloy electrocatalyst brings a significant impact in elevating its electrochemical oxygen reduction reaction activity. The sub-2 nm sized Pt3Co alloy particles evenly distributed over the carbon substrate could be prepared though a novel hot-injection method and it's substantially high performance could be validated for PEM fuel cell applications.

# G.P. and K.V.K. contributed equally; https://onlinelibrary.wiley.com/doi/10.1002/anie.202422609