Preparation of inorganic lead-free CuO/Cs2SnCl6-KI perovskite for green hydrogen production from wastewater by using solar energy

Abstract

Although lead halide perovskite materials have fascinating properties, the poisonous lead element and poor stability prevent their potential applications as photocatalysts. In this study, novel lead-free inorganic CuO/Cs2SnCl6-KI perovskites are used as efficient photocatalysts for the generation of H2 from wastewater. The chemical composition, morphological, structural, and optical properties were discussed using various techniques. The CuO/Cs2SnCl6-KI multilayers exhibit micro-stones with octahedral and hexagonal morphology, as well as an average particle size of about 2 µm. The band gap is 2.64 eV for CuO/Cs2SnCl6-KI multilayers. The X-ray diffraction data of the Cs2SnCl6 perovskite shows a cubic structure and average crystallite size of about 38.74 nm. Also, the X-ray photoelectron spectrum (XPS) was used to investigate the chemical composition of Cs2SnCl6-KI thin film. The photoelectrochemical (PEC) performance of the CuO/Cs2SnCl6-KI multilayers was evaluated in wastewater. The photocurrent density at −1 V (RHE) was −15.0 mA.cm−2. The incident photon-to-current conversion efficiency was 62.34 % under incident light with a monochromatic of 390 nm. Investigations are also conducted on photostability, thermodynamic characteristics, and electrochemical impedance of CuO/Cs2SnCl6-KI multilayers. As a result, a brand-new perovskite photoelectrode is introduced for the reliable and effective production of H2.