Experimental Study On Improving The Electrical Conductivity Of Carbon Nanotubes By Doping Transition Metal

Carbon nanotubes(CNTs)are among the most attractive materials in today's nanotechnology due to their outstanding electrical,thermal,and mechanical properties.However,one major barrier to many of the applications of CNTs is the high contact resistance between the CNTs and the electrode.Therefore,it has important research value to improve the electrical conductivity between CNTs and metal electrode by using gold doped CNTs to reduce the contact resistance between the electrode and the electrode.The gold atoms were doped with CNT by high temperature hydrogen reduction and electroless deposition.The CNT was reflued in nitric acid to achieve the defect structure of CNTs.The high temperature hydrogen reduction method is by immersing the CNTs after acid oxidation in the gold chloride solution containing gold ions,adsorption of gold ions,then the gold ions are reduced to gold atoms at high temperature,and the CNTs doping process is completed.First,the acid oxidized CNTs are soaked in the chloro gold acid solution which contains gold ions in order to adsorb gold ions.Then the gold ions are reduced to gold atoms by hydrogen at high temperatures.The acid oxidized CNTs into colloidal gold suspension made of sodium citrate and chloroauric acid,after a period of time,the gold nanoparticles will be deposited on the CNTs.The results show that the defects of the carboxyl,carbonyl and other oxygen bearing groups formed on the wall of the CNTs tube after the oxidation of nitric acid,which makes CNTs more promiscuous;Both high temperature hydrogen reduction and electroless deposition have completed the doping of gold atoms to CNTs and the gold nanoparticles on it are evenly distributed.The doping types of the two kinds of doping methods are all P type doping,and the gold content of the two methods is 0.18% and 0.24% respectively.Compared with the original CNTs,the contact resistance between the CNTs and the electrode of the samples of CNTs doped gold atoms which by high temperature hydrogen reduction and electroless deposition,is reduced by 69.20% and 71.49%.The CNTs doped gold atoms can effectively reduce the contact resistance of CNTs which will provide guidance for the research and application of CNTs in the field of nano electronics.