NiCoP modified lead-free double perovskite Cs2AgBiBr6 for efficient photocatalytic hydrogen generation

Abstract

Lead halide perovskites have exhibited promising achievements in the field of photoelectricity and photocatalysis. However, the toxicity of Pb hampers their practical application. Herein, an environment-friendly and Pb-free double perovskite, NiCoP/Cs₂AgBiBr₆ (NCP/CABB) composite, was successfully synthesised for the first time via efficient electrostatic coupling. It was applied for H₂ generation in an HBr solution. The NCP/CABB composite maintained a steric regular perovskite structure. The optimal 12.5% NCP/CABB composite achieved the highest H₂ generation rate (373.16 μmol g⁻¹ h⁻¹), which was approximately 88 times higher than that of pure CABB and was even better than that of CABB/5% Pt. Additionally, the NCP/CABB composite displayed excellent photocatalytic cycling stability in 4 h cycle tests. Due to the loading of NCP nanoparticles with preeminent conductivity, the separation and transfer of photoelectrons were promoted effectively, thereby enhancing photocatalytic performance. This work highlights a feasible strategy with broad prospects for the development of Pb-free perovskite composite catalysts.