1D/0D Z-scheme heterostructure of Bi2S3/CdXZn1−XS with strong interfacial electric field coupling enhanced mass transfer based on gas-liquid-solid micro interface contact for efficient photothermal synergistic catalytic CO2 reduction to syngas

Abstract

The reduction of CO2 to syngas by visible light-driven H2O is an attractive process, but this reaction is often limited by the poor mass transfer of CO2 in the liquid phase and the poor separation and mobility of photocatalyst carriers. In this paper, CdXZn1−XS nanospheres (CZS-X) uniformly decorated hollow Bi2S3 nanotube (H-BS NTs) heterojunction for photocatalytic CO2 reduction was successfully fabricated by in situ electrostatic self-assembly method. The yields of CO and H2 over 15 % H-BS NTs/CZS-0.5 was 32.11 μmol∙g−1∙h−1 and 33.10 μmol∙g−1∙h−1 without any sacrificial agent, which was 24.0 and −6.3 times than that of CZS-0.5, accordingly. The excellent activity was mainly attributed to the strong interfacial electric field (IEF) formed between H-BS NTs and CZS-0.5, which derived the rapid separation and transfer of charges dynamically. Meanwhile, the photo-thermal catalysis (PTC) with the novel gas-liquid-solid micro reactor inhibited efficiently the interface contact of the hydrogen evolution reaction and thermodynamically accelerated the rate of photocatalytic reduction of CO2. The accelerated photogenerated charge transfer was investigated in detail by density functional theory (DFT) calculations, in situ Kelvin probe force microscopy (IS-KPFM) and in situ X-ray Photoelectron Spectroscopy (IS-XPS). The results provided a new idea for promoting interfacial mass transfer, as well as photo-thermo-electric fields coupling to improve activity and selectivity.