Moisture Stable Soot Coated Methylammonium Lead Iodide Perovskite Photoelectrodes for Hydrogen Production in Water

Abstract

Metal halide perovskites have triggered a quantum leap in the photovoltaic technology marked by a humongous improvement in the device performance in a matter of just a few years. Despite their promising optoelectronic properties, their use in the photovoltaic sector remains restricted due to their inherent instability towards moisture. Here, we report a simple, cost-effective and highly efficient protection strategy that enables their use as photoelectrodes for photoelectrochemical hydrogen production while being immersed in water. A uniform coating of candle soot and silica is developed as an efficient hydrophobic coating that protects the perovskite from water while allowing the photogenerated electrons to reach the counter electrode. We achieve remarkable stability with photocurrent density above 1.5\xa0mA\xa0cm−2 at 1\xa0V versus saturated calomel electrode (SCE) for ~1\xa0h under constant illumination. These results indicate an efficient route for the development of stable perovskite photoelectrodes for solar water splitting.