Preparation And Performance Of Novel Ternary Composite Photoelectrocatalysts Based On Fe₂O₃-MoS₂

As one of environmentally friendly and novel treatment technologies,photoelectrocatalytic technology plays a very important role in solving the energy crisis and environmental pollution problems.The novel visible light driven photoelectrocatalysts are cirtical to the photocatalytic technology.We prepared Fe2O3-MOS2-Cu2O ternary photoelectrocatalytic film by electrodeposition method,hydrothermal method and electrophoretic deposition method.Scanning electron microscopy(SEM),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)were used to detect the surface characterization of the catalysts.The results showed that MOS2 and Cu2O were successfully loaded to Fe2O3 thin film,which changed the surface morphology of ternary material compared with unitary material and binary material.The composite electrodes exhibited better light response ability and photoelectric conversion efficiency.In addition,the incorporation of MOS2 and Cu2O films can effectively inhibit the recombination of photogenerated electron-hole pairs,and the photocatalytic performance of the electrode was obviously improved.Under visible light irradiation,the photocurrent density of Fe2O3-MOS2-Cu2O film at 0.38 V vs.Ag/AgCl was 20 times that of Fe2O3,and the photoelectric conversion efficiency was 2 times that of Fe2O3.The phenol was used as the target pollutant to investigate the photoelectric catalytic performance of electrode material for the degradation of refractory pollutants.The effects of various catalytic conditions,electrode materials,applied bias voltage and initial pH value on phenol removal were investigated systematically.The results showed that the degradation efficiency of ternary Fe2O3-MOS2-Cu2O was the best when the applied voltage was 2.5 V,the pH value was 6.3,and the initial concentration of pollutant was 10 mg/L.The photogenerated holes and hydroxyl radicals were considered as main active species through the analysis of the main active components in the degradation process.Fe2O3-MOS2/g-C3N4 was prepared by simple electrodeposition.Three kinds of electrode materials,Fe2O3,MOS2 and g-C3N4,coexisted on FTO substrate according to the characterization of SEM,XPS and XRD.Moreover,the ternary Fe2O3-MoS2/g-C3N4 material had higher photoelectric response.The photocurrent density of Fe2O3-MoS2/g-C3N4 film was 50 times that of Fe2O3,more than 5 times that of Fe2O3-MoS2,and 37 times that of Fe2O3-g-C3N4 under visible light.The photoelectric conversion efficiency of Fe2O3-MoS2/g-C3N4 was 3 times that of Fe2O3.Besides,the as-prepared Fe2O3-MOS2/g-C3N4 film was used as the anode to degrade phenol in the photoelectrocatalytical system.The ternary Fe2O3-MOS2/g-C3N4 electrode showed the best degradation efficiency of phenol and stability.The photogenerated holes and hydroxyl radicals were main active species.