Preparation And Characterization Of Carbon Nanotubes Supported Palladium And Gold Nanoparticles

Carbon nanotubes(CNTs),which with unique nano-structure,special electrical capability,fine flexility,absorption characteristic,good chemical and thermal stabilities, have attracted a great deal of attention in recent years.The composite material of carbon nanotubes and metal nanoparticles can be used as catalysts,sensors and fuel cell etc. Therefore,the method of deposition of metal nanoparticles upon carbon nanotubes and the study of their characteristics have become important subjects.The purpose of this paper is to explore simple and facile synthesis methods of metal nanoparticles/carbon nanotubes(CNTs) composite materials,followed by the research of their electrochemical properties,so as to make a solid foundation for their applications.The main work of this paper included:1.Treat the multiwalled carbon nanotubes(MWNTs) with strong acids and ultrasonic to generate carboxylic group along the sidewalls.Then polyethyleneimine(PEI) was introduced into the sidewalls through the static effect of groups to prepare functionized MWNTs which with positive charge on their surface.The functionized MWNTs was also characterized.2.Pd nanoparticles was successfully deposited on multiwalled carbon nanotubes (MWNTs) to get highly dispersed,nanovolum composite materials by reduction of H₂PdCl₄ using ethylene glycol(or 1,2-propanediol) both as solvent and reducing agent in the presence of polyvinylpyrrolidone(PVP) and sodium dodecyl sulfate(SDS).In addition, influencing factors such as the amount of PVP to H₂PdCl₄ and the temperature on the preparation of Pd/MWNTs were studied,and the composite materials were also characterized by means of XRD,UV-vis,CV and SEM.The conclusion that proper amount of PVP and SDS and the temperature are the important factors to prepare highly dispersed,nanovolum Pd/carbon nanotubes composite materials was stated.Furthermore, Pd/MWNTs composite materials also showed excellent electrocatalytic oxidation of methanol in basic medium.3.Gold nanoparticles was successfully deposited on multiwalled carbon nanotubes (MWNTs) to get highly dispersed,nanovolum composite materials by one-step reduction of PEI.Influencing factors such as the amount of PEI and the temperature on the preparation of Au/MWNTs were studied,and the composite materials were also characterized by means of SEM,XRD,UV-vis.Au/carbon nanotubes composite materials prepared by self-assembly method which embodied simple process,opera-tion easy and ambient experiment conditions.Besides,strong combination effect was also showed between gold nanoparticles and the surface of carbon nanotubes,which could maintained even rinsing with ultrasonic for several times.