Photoelectrochemical systems (PECs) using halide perovskite-based photoelectrodes are receiving tremendous attention as promising technology for clean hydrogen production. Remarkably, the high absorption coefficient, high charge mobilities, and tunable optical and electrical properties of perovskite materials enable the achievement of a theoretical solar-to-hydrogen (STH) efficiency as high as 28.7%. However, they suffer from the lack of stability specially against the water molecules. In this work, a PEC cell comprising a perovskite-based photoanode with the ITO/ electron transport layer/perovskite/hole transport layer / top electrode structure is fabricated. The morphology and optical properties of the perovskite layer are studied. The device shows a photovoltaic power conversion efficiency of 14%. To prevent water-driven degradation of the photoelectrode, the top electrode is specially designed. A hydrophobic carbon-based layer serves as the top contact. Subsequently, a partially coated ITO with a Ni-based catalyst is applied on the carbon layer to facilitate the water-splitting reaction. With the engineered contact, the photoelectrode stability improves significantly compared to the Au-contact device, which degrades within a few seconds.
