Unassisted overall water splitting with a solar-to-hydrogen efficiency of over 10% by coupled lead halide perovskite photoelectrodes

Abstract

Hydrogen is a promising future sustainable fuel candidate with boundless opportunities. Research into photoelectrochemical (PEC) water splitting based on a lead halide perovskite (LHP) has progressed significantly with the aim of more efficient solar hydrogen production. Herein, we unite a well-known photo-absorbing LHP with cost-effective water-splitting catalysts, and we introduce two types of monolithic LHP-based PEC devices that act as a photocathode and a photoanode for the hydrogen evolution reaction and oxygen evolution reaction, leading to efficient unbiased overall water splitting. Through the integration of these two monolithic LHP-based photoelectrodes, an unbiased solar-to-hydrogen conversion efficiency of 10.64% and a photocurrent density of 8.65 mA cm−2 are achieved.