Preparation Of Metal Nanocatalysts And Catalytic Performance

With the rapid development of nanotechnology,nanomaterials technology has begun to rise.Due to its small particle size,high specific surface area and high catalytic activity,nanomaterials have become an indispensable part of all kinds of industries.Nano catalysts are widely used in organic,inorganic reaction catalysis,the preparation of new energy,sewage treatment and so on.Nanomaterials and nanocomposites prepared by hydrothermal synthesis can be applied to catalyze organic,inorganic reactions,new energy sources and sewage treatment.The research contents of this paper are as follows:The first chapter is a summary of the introduction,properties,classification,catalytic applications,and synthesis methods of nanoscale catalysts.The second chapter: we synthesized 6 different palladium nanoparticles?Pd NPs?including twenty surface,sphere,spindle,cube,rod and line by hydrothermal synthesis.The morphology and composition of the six catalysts were characterized by transmission electron microscopy?TEM?,scanning electron microscopy and X ray diffraction.We also study their catalytic activity by reducing the reaction of Cr?VI?and Suzuki coupling.We found that the catalytic activity is closely related with surface area,the size of the order is: Icosahedron > sphere > rod > spindle > cube.Palladium icosahedron shows better catalytic performance in the reduction of Cr?VI?than that of other Pd NPs,with a rate constant of 0.42 min-1.The third chapter: We developed a simple one-step hydrothermal method to prepare three kinds of nanometer materials are: two-dimensional?2D?MoS₂ nanosheets,threedimensional?3D?spherical Cu S nanoparticles,and three-dimensional?3D?MoS₂/Cu S nano hybrid bulk heterojunction structure and its characterization.We found that the morphology of MoS₂/Cu S nanocomposites is different from that of MoS₂ nanoscale and Cu S nanoparticles.The electrochemical method was used to study the hydrogen evolution?HER?activity of MoS₂ nanoscale,Cu S nanoparticles and MoS₂/Cu S nanohybrids.The HER activity of MoS₂/Cu S nanocomposites is better than that of MoS₂ nanosheets and Cu S nanoparticles,which can be attributed to the good electron transport ability of Cu S and the strong reduction ability of MoS₂ to hydrogen ions.The MoS₂/Cu S nanohybrid catalysts for three-dimensional flower like heterostructures exhibit great potential in the application of renewable energy.