Preparation Of Porous Gold Nanoparticles And Study On Their Catalytic Performance

As a noble metal,gold has been used as currency and artificial jewelry for thousands of years.The rapid development of nanotechnology at the beginning of this century has changed the role of gold in human production and life.Over the past 20 years,gold nanomaterials with different sizes,morphologies,and surface modifications have been reported successively.With extraordinary physical and chemical properties,nanogold shows great potential in imaging,thermal diagnosis,sensing,and catalysis.In practical applications,the physical and chemical properties of gold nanomaterials are highly dependent on its structure and the surface properties,which affects its practical usage in various fields.Therefore,it is important to develop efficient,convenient,and environmentally-friendly synthetic routes to customize the gold nanomaterials with different structures and our work expanded from this.The research content of this article is mainly divided into the following three parts:1)We have designed synthetic routes based on the"one-pot method",soft template method and hard template method to prepare NH₂-PEG₃-SH modified gold nanoclusters??0.93±0.19?nm?,porous gold nanoparticles??47.9±6.4?nm?and NH₂-SiO₂@Au nanoparticles.During the preparation of porous gold nanoparticles,by adding ascorbic acid as a reducing agent,we also produced by-product regular hexagonal gold nanosheets.2)Using borohydride to reduce nitrophenol compounds as a model reaction,the ability of porous gold nanoparticles to catalyze the reaction was tested via the kinetic analysis method.Results of catalytic experiment showed that the apparent rate constant of p-nitrophenol catalyzed by porous gold nanoparticles could reach 0.95×10^-2·s^-1,which is better than most reported gold catalysts.By changing the amount of Pluronic F127,the morphology and catalytic performance of nanoparticles we gained could be adjusted.3)With strong absorption in the near-infrared band,the photothermal conversion ability of prepared hexagonal gold nanosheets was tested by laser irradiation.The results showed that the temperature of regular hexagonal gold nanosheets could rise to 60.1?after laser irradiation,which has the potential to be applied in the field of photothermal therapy.