Organic-inorganic hybrid perovskite – TiO2 nanorod arrays for efficient and stable photoelectrochemical hydrogen evolution from HI splitting

Abstract

Solar-driven photoelectrochemical (PEC) hydrogen production offers a promising solution to simultaneously tackle the global energy crisis and the environmental pollution. Herein, we report a PEC cell of organic-inorganic hybrid perovskite (methylammonium lead iodide, MAPbI3)-TiO2 nanorod array (TNAs) for efficient and stable hydrogen evolution in aqueous hydrogen iodide (HI) solution. The built-in electric field created across the MAPbI3-TiO2 junction is able to efficiently separate the electron-hole pairs photogenerated in MAPbI3 with electrons quickly injected from MAPbI3 to TiO2, which are then transported along the one-dimensional TiO2 nanorod channels to the counter electrode to reduce proton to evolve hydrogen. The optimized MAPbI3-TNA PEC cell exhibits a high photocurrent density of 1.75 mA cm−2 at 0.14 V (vs. Ag/AgCl) under AM 1.5G illumination, which is able to stably produce molecular hydrogen at a rate of 33.3 μmol cm−2 h−1 for more than 8 h.