Synthesis of interfacial electric field-enhanced CdS/CdxZn1-xS/ZnO ternary heterojunction by lye dissolution etching mechanism for photocatalytic H2 production and CO2 reduction

Abstract

The difficulty in fabricating a multifaceted composite heterojunction system based on CdxZn1-xS limits the enhancement of photocatalytic performance. In the present scrutiny, novel ZnO/CdxZn1-xS/CdS composite heterojunctions are successfully prepared by the alkaline dissolution etching method. The internal electric field at the interface of I-type and Z-scheme heterojunction improved the effective charge separation. The ZC 8 sample exhibits excellent photocatalytic performance and the H2 production efficiency is 15.67 mmol g−1 h−1 with good stability up to 82.9 % in 24-hour cycles. The performance of CH4 and CO capacity in the CO2RR process is 3.47 μmol g−1 h−1 and 23.5 μmol g−1 h−1, respectively. The photogenerated accelerated charge transport is then examined in detail by in situ X-ray photoelectron spectroscopy (ISXPS) and density functional theory (DFT) calculations. This work presents a new idea for the synthesis of CdxZn1-xS solid-solution-based materials and provides a solid reference for the detailed mechanism regarding the electric field at the heterojunction interface.