Study On Synthesis And Photocatalytic Performance Of Ternary Chalcogenide And Its Composites

Semiconductor photocatalytic technology is developed rapidly in recent years can which can use solar energy for environmental purification and transformation,energy transformation,organic synthesis and CO2 reduction.It is a kind of lean technology with high efficiency,no secondary pollution under room temperature and pressure conditions.Ternary chalcogenide is a compound with unique electronic and optical properties as well as good light and chemical stability,which has been wide attention of researchers.However,metal sulfides that photogenerate charge carriers with low separation efficiency and recombination seriously has limited their large-scale practical application.Rational construction multicomponent materials can realize the complementary components function together,which is expected to solve the bottleneck problem of low photocatalytic efficiency.In this paper,we focus on CaIn2S4(CIS)and Zn0.5Cd0.5S(CZS-0.5)as the research object.Through constructing CIS/CEO and CZS-0.5/WO2 two kinds of nanocomposites,investigating photocatalytic performance of ternary chalcogenide and its copposites.The main research content is as follows:(1)In this paper,by means of hydrothermal,we synthesis CIS with flower structure and CEO nanoparticles respectively.Then,new type of micro/nano-sized hybrids was synthesized based on the assembly of CEO nanoparticles onto marigold-flower-like CIS microspheres via a wet-impregnation method that based on two components with the surface of the different charge in the pure water.The research results show that the close contact and matching band position between CIS and CEO is beneficial to promote the separation of electrons and holes,improving the photocatalytic activity of selective oxidation benzyl alcohol.(2)we successfully synthesis WO2 with nanorod structure by using the method of hydrothermal and thermal reduction and then synthesis CZS-0.5/WO2 composite materials through the wet-impregnation and inert gas heat treatment method.Research results show that the metallic WO2 can reduce the over potential of photocatalytic hydrogen production,promote the separation of electrons and holes and improve photocatalytic water splitting activity under the visible light.The innovation points of this paper as follows:(1)New type of micro/nano-sized hybrids was synthesized based on the assembly of CEO nanoparticles onto marigold-flower-like CIS microspheres via a wet-impregnation method that based on two components with the surface of the different charge in the pure water.(2)For the first time,we used CIS/CEO nanomaterials for selective oxidation reaction of benzyl alcohol to benzaldehyde under visible light.The possible reaction mechanism was also proposed.(3)We first successfully prepared CZS-0.5/WO2 composite materials.The possible photocatalytic hydrogen production reaction mechanism was proposed based on the electrochemical methods.