An organometal halide perovskite photocathode integrated with a MoS2 catalyst for efficient and stable photoelectrochemical water splitting

Photoelectrochemical water splitting using organometal halide perovskites (OHPs) is an attractive and sustainable method for converting solar energy to hydrogen (H-2). However, the poor stability of OHPs in aqueous electrolytes and the use of Pt, a noble metal, as a hydrogen evolution reaction (HER) catalyst restrict the practical application of OHP-based photocathodes. Herein, we report an efficient and stable OHP-based photocathode using Ti foil as the protective encapsulation layer and earth-abundant and cost-effective MoS2 as the HER catalyst. The fabricated MoS2/Ti foil/OHP photocathode presents a remarkable half-cell solar-to-hydrogen conversion efficiency of 11.07%, a photocurrent density of -20.6 mA cm(-2) at 0 V versus the reversible hydrogen electrode (vs. RHE), and an onset potential of 1.02 V vs. RHE. Furthermore, the MoS2/Ti foil/OHP photocathode exhibits a record long-term PEC stability in aqueous electrolytes over 120 h of illumination. Our study provides insights into designing the structure of OHP-based photocathodes for efficient and stable solar H-2 production.

Automated summary

The study presents an efficient and stable OHP-based photocathode using Ti foil as the protective encapsulation layer and MoS2 as the HER catalyst, showcasing significant solar-to-hydrogen conversion efficiency and long-term stability in aqueous electrolytes.