Preparation Of Palladium-based Catalyst And Study On Electrocatalytic Performance Of Methanal

Catalytic activity of the catalyst played a critical role for methanol fuel cell.At present,the most commonly used catalyst material is platinum(Pt)based catalyst.Commercials applications are limited by lack of resources,the high cost related to metal catalysts and the poisoning caused by intermediate carbonaceous species.In this paper,Pd was used as the base material and several kinds of materials were used as catalysts.The electrocatalytic activity and electrochemical stability of methanol were studied.The catalysts of Pd/RGO,Pd/PDDA-RGO,Pd/Mg O-RGO and Pd/Mg O-PDDA-RGO were prepared.The as-prepared material was characterized by transmission electron microscopy(TEM)and X-ray diffraction(XRD).The electrochemical behavior of Pd/RGO,Pd/PDDA-RGO,Pd/Mg O-RGO and Pd/Mg O--PDDA-RGO for ethanol oxidation was studied using cyclic voltammetry(CV)and chronoamperometry(CA)methods.The ratio of forward anodic peak current density(If)to reverse anodic peak current density(Ib)value could be used to explain the oxidation to methanol and tolerance to theintermediate carbonaceous material.The value of If/Ib of Pd/RGO,Pd/PDDA-RGO,Pd/Mg O-RGO and Pd/Mg O-PDDA-RGO was 1.57,1.68,2.87 and 3.23,it increased.The results showed that Pd/Mg O-PDDA-RGO exhibits higher electrocatalytic activity and better resistance to CO poisoning.I0 is the stable forward anodic peak current density of the first cycle,In is the forward anodic peak current density of the nth cycle.The value of I0/In is be used to evaluate the stability of the catalyst.In/I0 on Pd/Mg O-PDDA-RGO is still 83% after 1000 cycles,which is higher than 78%,71% and 69% of the Pd/Mg O-RGO,Pd/PDDA-RGOand Pd/RGO.Theresultsindicated that Pd/Mg O-PDDA-RGO exhibits higher electrocatalytic activity and better stability.The catalysts of Pd/RGO and Pd/EDTA-RGO were prepared.The electrochemical behavior of Pd/RGO and Pd/EDTA-RGO for ethanol oxidation was studied using cyclic voltammetry(CV)and chronoamperometry(CA)methods.The value of If / Ib on Pd/EDTA-RGO is 1.08 times as largr as that on Pd/RGO.The value of In/I0 on Pd/EDTA-RGO is still 79% after 1000 cycles,which is higher than 69% of the Pd/RGO.The results indicated that Pd/EDTA-RGO exhibits higher electrocatalytic activity and better stability.Pd/Mg O-PDDA-RGO and Pd/EDTA-RGO were used to compared for methanol electrocatalytic activity and stability.The value of If / Ib on Pd/ Mg O-PDDA-RGO is 2.56 times as largr as that on Pd/EDTA-RGO.The value of In/I0 on Pd /Mg O-PDDA-RGO is still 83% after 1000 cycles,which is higher than 79% of the Pd/EDTA-RGO.The results indicated that Pd/Mg O-PDDA-RGO exhibits higher electrocatalytic activity and better stability.