Achieving Organic Metal Halide Perovskite into a Conventional Photoelectrode: Outstanding Stability in Aqueous Solution and High-Efficient Photoelectrochemical Water Splitting

Organic metal halide perovskite material has attracted intense interest in the photovoltaic field due to its excellent optoelectronic properties, but the extreme susceptibility of organolead halide perovskite to water seriously impedes its application for photoelectrochemical (PEC) conversions in aqueous solution. In this work, we develop an organolead halide perovskite photoanode of conventional electrode structure. The perovskite photoanode was fabricated by using a facile approach and encapsulated with conductive carbon paste and silver conductive paint for waterproof function, and the PEC water splitting was carried out as a model of PEC conversion. For PEC water oxidation, the photoanode achieved a remarkable photocurrent density of 12.4 mA/cm2 at 1.23 V versus reversible hydrogen electrode in alkaline electrolyte. In addition, the as-prepared photoanode of conventional structure exhibited an unprecedented stability, which could be stable in alkaline electrolyte for more than 48 h. More importantly, the photoanode retained a steady-state response in a continuous operation for at least 12 h in electrolyte at a wide pH range. This work opens a promising avenue toward the practical application of organic metal halide perovskite-based photoelectrodes for efficient PEC conversions in aqueous solution.