Preparation And Perfomance Studies Of Ptco Composited Catalyst For Direct Methanol Fuel Cell

A lot of attention has been paid to direct methanol fuel cell because of its simple structure,rich source of fuel and high efficiency.The process of commercialization of DMFC was accelerated by use of Pt based catalyst,the antipoisoning ability and the utilization rate of catalyst improved,the stability of catalyst and oxidation rate of methanol enhanced,the service life of the battery output power density of DMFC extend.The PtCo nanocomposited particles supported on graphene as a catalyst for methanol oxdation was studied in the paper.First of all,the graphene oxide was prepared by the improved Hummers method then reduced to graphene by sodium borohydride.PtCo/ZrO₂-RGO,PtCo-PDDA-RGO,PtCo-3D RGO were prepaed with acid chloride platinum and cobalt chloride as the precursor and the electrocatalytic performance of products for methanol oxidation and stability were investigated.The structures and morphology of the catalysts were characterized by XRD?SEM and TEM,the electrocatalytic performance for methanol oxidationwas detected by Cyclic Voltammetr?CV?and Chronoamperometry?CA?.The results showed that the particle sizes of the prepared catalysts were uniform dispersion.The electrocatalytic oxidation efficiencies and cycle stabilities of catalysts for methanol were invested by CV and CA,the ratios of the peak current density values by positive scan and negative scan corresponding to Pt-RGO,PtCo-RGO and PtCo/ZrO₂-RGO were respectively 0.65,2.57 and 3.32,after 1000cycles,the I_n/I₀ values for Pt-RGO,PtCo-RGO and PtCo/ZrO₂-RGO were 65%,78%and86%,the I_n/I₀ value of PtCo-PDDA-RGO is 88%,the results prove the stabilities the latter was excellent.Finally,three triimensional graphene was obtained by hydrothermal synthesis.The PtCo/3D RGO composite catalyst was synthesized by the chemical reduction method of PtCo bimetallic nanoparticles.The peak current density value ratios of positive and negative sweep corresponding to PtCo-RGO,Pt-3D RGO and PtCo-3D RGO were respectively 2.57,3.23 and5.32.The rate of Current decay on catalyst PtCo-3D RGO was slower than on PtCo-RGO and Pt-3D RGO.The current density of the final steady state value is highest,which proved that PtCo-3D RGO catalyst had superior catalytic performance and electrochemical stability.The linear correlation coefficient between peak current density and the square root of scan rate of R²=0.987.The composited catallysts PtCo/ZrO₂-RGO,PtCo-PDDA-RGO and PtCo-3D RGO had a lot of excellent performances,such as high catalytic performance,antipoisoning to CO and good stability,the reaction rate of methanol oxidation on anode the were greatly accelerated by the catalysts.