Synergistic effect of noble metal modified LaNiO3 perovskites for photocatalytic water splitting

Abstract

Harnessing the solar energy to produce valuable fuels is a promising solution to the global energy crisis. One such vital fuel is hydrogen and it can be produced through the efficient evolution from water using a judiciously chosen perovskite photocatalyst. Perovskite materials, with their distinctive structural and optical properties, emerge as potential catalysts for visible light photocatalytic water splitting. Among these, LaNiO3 stands out as a promising photocatalyst due to its small bandgap and well-suited band edges that enable efficient visible light absorption. Strategic modifications with noble metals further elevate the photocatalytic performance. Utilizing the solution combustion method, catalysts are synthesized and extensively characterized through techniques such as XRD, XPS, ICP-OES, SEM, BET, DRS, UPS, Photoluminescence, and Time-resolved photoluminescence. Photocatalytic hydrogen evolution studies are conducted under solar simulator illumination. Notably, the addition of noble metals increased the photocatalytic activity from 1.37 mmol g-1 h-1 to 20.86 mmol g-1 h-1 while the apparent quantum efficiency varied from 2.58% to 39.42%. The TOF on the basis of the active sites varied from 214.44 h-1 to 1685.24 h-1. The catalysts demonstrate stable and consistent performance over a 12-hour duration. The photocatalytic H2 yield trend was found to be Rh/LaNiO3 > Ru/LaNiO3 > Ir/LaNiO3 > Pt/LaNiO3 > LaNiO3.