Construction Of Heterogeneous Structure Of Metal Sulfide And Study On Hydrogen Production Performance By Visible Light Catalysis

Semiconductor photocatalytic decomposition water to hydrogen can convert solar energy into clean and sustainable hydrogen energy is an environmentally friendly technology.The principle of the semiconductor photocatalytic hydrogen production:when the radiation energy is greater or equal to the width of the band gap of the semiconductor,the electron from semiconductor valence band was photon excited from the valence band to the conduction band,Lead there are holes in the valence bandvalence and on the surface of the semiconductor,the redox reaction occurs on the surface of the proton or water molecules.The design and fabrication of the semiconductor catalyst has the practical application value,the preparation is a bottleneck in the development of hydrogen production by photocatalytic decomposition of water.Broaden the visible spectral response range and improve the hydrogen production activity is the key to the preparation of semiconductor catalyst design.In order to solve the existing problems of semiconductor photocatalyst,it is necessary to design and prepare photocatalysts with good stability,visible light response and high hydrogen activity.Compared with the commonly used wide band gap semiconductor,metal sulfide semiconductor usually have relatively narrow band gap,and the narrow band gap semiconductor research more,some compound wide band gap semiconductor heterostructures prepared by metal sulfide can greatly improve the photocatalytic activity to absorb visible light,and enhance effective use of solar energy in more a large extent.Therefore,in order to make better use of sunlight,we synthesized composite metal sulfide heterostructures for development photocatalytic decomposition of water to hydrogen has important significance.The main contents of research as follows:1.By a simple solvothermal method to synthesize uniform morphology of flower like hierarchical structure of hexagonal ZnIn2S4 microspheres,continue to load the cubic ZnIn2S4 particles,respectively using zinc nitrate as source of zinc,indium nitrate as indium source,L-cysteine hydrochloride and thioacetamide as sulfur source,ethanol as solvent,successfully synthesized ZnIn2S4 with different phase structure.There are two kinds of crystalline structure of the ternary ZnIn2S4 as research object to construct the heterogeneous structure,through the study of homogeneous phase structure,analysis relationship of the load on the performance of hydrogen production to improve the photocatalytic activity of catalyst for hydrogen production.In this paper,the morphology of the complex was controlled by changing the concentration of the raw material,The effect of loading on the composite photocatalyst was studied systematically,including crystal phase,optical absorption properties,specific surface area and light affect about the catalytic performance of hydrogen production.2.In this part,the ZnS nanowires were synthesized by a simple solvothermal method,and the ZnS/lIn2S3 binary nanowire heterostructures were further constructed.zinc acetate was used as zinc source,sodium sulfide as the sulfur source,indium nitrate as indium source,ethylene glycol and ethylenediamine as solvent was successfully synthesized ZnS/In2S3 binary nanowire heterostructures.By regulating the introduction of In3+,to control the morphology of the heterostructures,so as to find out the best hydrogen production performance of this heterogeneous structure.In addition,to contrast ZnS/In2S3 binary nanowire heterostructures and pure ZnS nanowires,there are more excellent photocatalytic hydrogen production performance and stability.3.The synthesis of ZnS/In2S3/AgInS2 ternary nanobelts heterostructures by solvothermal,hydrothermal and ion exchange methods,using zinc acetate as zinc source,sodium sulfide as the sulfur source,indium nitrate as indium source,and through control the amount of solvent of ethylenediamine to decide the morphology as a key step.Finally,through the introduction of Ag+ to successfully synthesized ternary nanobelts heterostructures materials,ternary element heterostructures prepared composite compared with single component ZnS and ZnS/In2S3 binary heterojunction to show better photocatalytic hydrogen production under visible light.Therefore,the last step by adding Ag+ in the fabrication process to preparation ternary heterostructure to improve the photocatalytic performance produced.At the same time greatly improves the photocatalytic performance and stability.