Preparation Of Sulfide Semiconductor Heterojunction/Electrospun Fiber Composite And Photocatalysis Of Hydrogen Evolution

In this paper, we prepared conducting PVDF-SMA fiber with interconnected openpore structure and good photocatalytic resistance ability by electrospinning method.Chalcogenide Semiconductor heterostructure photocatalysts were immobilized ontothe surface of conducting PVDF-SMA fiber by hydrothermal synthesize. Thephotocatalytic activity of the composites was investigated from the hydrogenproduction by water decomposition both under UV irradiation and visible light.（1） SnS-SnS₂particles were uniformly synthesized on the surface of conductivePVDF-SMA fibers through a hydrothermal synthesis followed by characterizationusing X-ray diffraction （XRD）, scanning electron microscopy （SEM）, X-ray electronspectrum （XPS）, transmission electron microscope （TEM）, ultraviolet visible diffusereflectance spectrum （UV-VIS） and thermogravimetric analysis （TGA）. UV-VISabsorption spectra showed that the composites could absorb the visible light. Theelectrospun fiber showed no influence during the photocatalytic profermance. Thedegradation rate of SnS-SnS₂/electrospun fiber composites from methyl orange was82.9%under visible light simulated by Xe lamp. It was found that the as-preparedSnS-SnS₂/PVDF-SMA fiber composites have improved stability and activity in H2generation from water compared with SnS-SnS₂powders. The average rate of H2evolution from water using SnS-SnS₂/PVDF-SMA fiber composites was5.92mL per2hours.（2） PbS-ZnS particles were uniformly synthesized on the surface of PVDF-SMAfibers through a hydrothermal synthesis. UV-VIS absorption spectra showed that thecomposites could absorb the UV irradiation without the influence of electrospun fiberduring the photocatalytic activity. Compared with the PbS-ZnS/PVDF-SMA fiber, P25and PbS-ZnS powders, the composites exhibited the best photocatalytic efficiency inthe degradation of methy orange aqueous solution with a degradation rate of1.23%. Itwas found that the as-prepared PbS-ZnS/PVDF-SMA fiber composites have improvedstability and activity in H2generation from water compared with PbS/ZnS powders. The average rate of H2evolution from water using PbS-ZnS/PVDF-SMA fibercomposites was10.45mL per2hours.（3） In₂S₃-TiO₂particles were uniformly synthesized on the surface of conductivePVDF-SMA fibers through a hydrothermal synthesis. SEM showed that TiO₂nanoparticles were wrapped up on the fibers, then the acicular In₂S₃were despered onthe TiO₂. Using Xe lamp irradiation as visible light stimulation, the compositesshowed a degradation rate of3.23%in the degradation of methyl orange aqueoussolution. It was found that the as-prepared In₂S₃-TiO₂/PVDF-SMA fiber compositeshave improved stability and activity in H2generation from water compared withIn₂S₃-TiO₂powders. The average rate of H2evolution from water using In₂S₃-TiO₂/PVDF-SMA fiber composites was15.29mL per2hours.