Morphology effect of perovskite CsPbBr3/g-C3N4 composite on photocatalytic water-splitting for hydrogen evolution

The urgent global need for clean, renewable energy has fueled extensive research into effective photocatalysts for hydrogen (H 2 ) production. While cesium lead halide perovskites (CsPbX 3 , X = Cl, Br, and I) have shown promise for visible light absorption, g-C 3 N 4 is recognized for its stability and Solid UV absorption spectra were recorded using diffuse reflectance on 10 mg powder samples pressed into uniform pellets to ensure a consistent illuminated area. Herein, two types of CsPbBr 3 perovskites with the morphology of nanosheet (PNS) and nanocrystals (PNC) are synthesized using supersaturated recrystallization and aqueous phase exfoliation method, respectively, and then combined with the g-C 3 N 4 to fabricate CsPbBr 3 perovskite/g-C 3 N 4 composites in different ratios, respectively. The as-prepared composites were tested as photocatalysts in water-splitting reactions to create H 2 in visible light conditions. The photocatalytic results revealed that 60 % PNS/g-C 3 N 4 and 20 % PNC/g-C 3 N 4 had the highest hydrogen evolution rate (HER) of approximately 2707.08 μmol∙h −1 ∙g −1 and 2299.17 μmol∙h −1 ∙g −1 , respectively, surpassing the HER of both pristine CsPbBr 3 and pure g-C 3 N 4 , which are 1.65 and 1.40 times higher than authentic g-C 3 N 4 . This research draws attention to the remarkable potential of CsPbBr 3 /g-C 3 N 4 composites in achieving efficient HER for H 2 production among their respective series.