Preparation And Electrochemical Investigation Of Pt/Graphene Electrode Of Direct Methanol Fuel Cell

Direct methanol fuel cell is a renewable green energy,and the anode catalytic performance is a key factor affecting the efficiency,activity and cost of direct methanol fuel cell.Therefore,the development of high-efficiency,low-cost anode catalyst is of great significance.The Pt/graphene nanomaterials with different loadings of Pt were prepared by ultrasonic method in one-step process,and the electrochemical properties of the nanomaterials for methanol electrooxidation are studied.The work is summarized as follows:1.The nano-Pt/graphene?Pt,25 wt%?was prepared by one-step method,and the morphology and structure of the product were characterized by powder X-ray diffraction?XRD?,scanning electron microscopy?SEM?,and transmission electron microscope?TEM?.The nano-Pt/graphene and Pt nanoparticles were dropped on the surface of GC to prepare the Pt/graphene-modified electrode?Pt-G/GC?and the Pt-modified electrode?Pt/GC?.The electrocatalytic activity of the modified electrodes for methanol oxidation in acidic solution was investigated by electrochemical method.The results showed the catalytic oxidation process of methanol was controlled by a diffusion process.The Pt-G/GC had higher electrocatalytic activity and stability for methanol oxidation than Pt/GC,which could significantly increase the catalytic active surface area of the electrode and accelerated charge transport and transfer performance.2.The Pt/graphene with different loadings of Pt were prepared by one-step process,the morphology and structure of the products were characterized by XRD and SEM.The results showed that the average size of Pt nanoparticles changed little with the increase of the amount of Pt precursors.The Pt/graphene with different loadings of Pt were dropped on the surface of GC to prepare the Pt-G/GC.The electrochemical results showed when the loading of Pt amount on graphene was 40%,the Pt-G/GC had the largest electrochemical active surface area,which could increased the catalytically active surface area of the electrode significantly,and accelerated charge transport as well as transfer performance.and the electrocatalytic activity and stability for methanol oxidation were the highest.The diffusion coefficient of methanol on Pt-G/GC was 8.52×10^-99 cm²·s^-1.Therefore,40%was the optimal range of the amount of Pt on graphene.