Coordination Self-assembly Synthesis Of N-modified Carbon-supported Gold Nanocatalyst And Its Application In The Reaction Of Benzyl Alcohol

Since the 20 th century,ordered mesoporous materials with its high specific surface area,unique pore structure,and large pore size have shown great applications in various fields,such as separation and adsorption,catalysis,electricity Chemicalandbiomedical fields.Within the mesoscale scale,a uniform pore structure that penetrates each other can possess excellent properties such as high porosity and molecular sieves,then promote the diffusion and transport of molecules.Therefore,we propose a novel preparation method to synthesize Au/C catalysts.This mesoporous material has a highly ordered face-centered cubic structure and a larger specific surface area.The pore size can be adjusted in the range of 6-10 nm by changing the proportion of the hydrophobic end of the surfactant.At last,the catalyst shows high catalytic activity and selectivity when applied to the selective oxidation of benzyl alcohol and its derivatives.The paper is divided into four chapters.The first chapter is the literature review.It mainly introduces the research status of mesoporous materials,the method of regulating carrier pore size and the research status and application background of gold nanoparticles.The second chapter introduces a one-step method for synthesizing macroporous Au / C catalyst materials.Firstly,a series of different molecular weight amphiphilic block copolymers polystyrene-block-poly(4-vinylpyridine)(PS-b-P4VP)was synthesized by reversible rupture addition chain transfer(RAFT)).Then,the block copolymer was used as the template agent,the phenolic resin was used as the carbon source and the chloroauric acid solution as the gold source.The Au/C catalyst with high pore size was obtained by solvent evaporation self-assembly(EISA)and high temperature calcination.The N element in the template by coordination with Au in the gold source in order to fix the gold nanoparticles.XRD,BET,TEM and other characterization methods show that the catalyst has a highly ordered face-centered cubic structure,uniform and largechannels,small and evenly distributedgold nanoparticles.By changing the ratio of hydrophilic to hydrophobic ends,the pore size can be adjusted in the range of 6-10 nm.The pore size of the carrier gradually increases,and the size of the gold nanoparticles gradually decreases with the increase of the molecular weight of the PS end.In the third chapter,the Au/C catalysts with large pore size were studied by oxidation reaction of benzyl alcohol and the catalytic performance of selective oxidation of alcohols with different substituents.The effect of pore size and pore structure on the reaction rate was investigated by comparing Au/C with larger pore size and Au/C with two-dimensional hexagonal structure.The experimental results show that the Au/C catalyst with high pore size exhibits high catalytic activity in alcohol compounds with different steric hindrance,and the catalyst still has high catalytic activity after repeated times.The activity of the catalyst was keep high after the thiolated SBA-15 was introduced into the reaction system.This indicates thatthe reaction does not exist a loss of Au species and the catalyst had high stability.The fourth chapter is the summary of the full text...