Photoinduced deposition of cubic Pd on the edge active sites of BiOCl to enhance photocatalytic CO2 reduction performance

Abstract

BiOCl photocatalytic materials were prepared using a hydrothermal method, and the cubic Pd was loaded on the active edge sites of BiOCl using a photoinduced deposition method to enhance photocatalytic CO₂ reduction. The photoelectrochemical tests demonstrate that the cubic Pd cocatalyst loaded on the edge active sites improves the charge separation ability and facilitates the activation of CO₂ molecules. Benefiting from the strong proton adsorption capacity of Pd, the CH₄ evolution rate of 0.3 % Pd/BiOCl reaches 0.16 μmol∙g⁻¹∙h⁻¹, which is 11.3 times higher than that of BiOCl. According to in-situ DRIFT analysis, after loading the Pd cocatalyst, CO* does not directly form CO, but forms intermediates such as CHO* and CH₃*, thereby suppressing the formation of CO and improving the selectivity for CH₄ production. This work helps to understand the mechanism of CO₂ reduction and provides ideas for regulating the selectivity of CO₂ reduction.