Construction And Electrochemical Performance Of Bimetal Oxide For Direct Methanol Fuel Cell

With the depletion of fossil energy and the environmental pollution,direct methanol fuel cells?DMFC?have become one of the most attractive mobile energy conversion devices due to their small volume,high theoretical energy density,environmentally friendly and abundant fuel resource.However,the problems of catalyst such as high cost,weak resistance towards CO poisoning,and unsatisfactory activity and stability make the commercialization of direct methanol fuel cells difficult.Therefore,promoting the utilization of precious metals to reduce the cost of catalysts and increasing the activity and stability of the catalysts is an important way to accelerate the commercialization of DMFCs.Based on the above objectives,in this work,we carried out basic research work on improving the electrocatalytic activity,stability and producing cost of DMFC anode catalysts.The main contents as listed as follows:?1?The nickel-molybdenum double metal oxide is combined with the graphene by a simple one-step hydrothermal method as a Pt-based catalyst carrier for MOR.The effects of Ni/Mo atomic ratio,hydrothermal time,relative content of precursor and graphene on the performance of the catalyst were investigated.When the hydrothermal time is 12 h,Ni/Mo is 1/1 and the volume ratio of oxide to graphene is 1/4,the performance of catalyst Pt-Ni₁Mo₁O_x/GO is the most superior,and its mass specific activity achieved 2102 mA mg_Pt^-1.After 3600s chronoamperometry test,the mass specific activity of Pt-Ni₁Mo₁O_x/GO remained 813 mA mg_Pt^-1 and the retention rate is40.15%,showing good stability and resistance to CO poisoning.?2?CoMoO₄ was in-situ coated on the Co,N co-doped carbon polyhedron?Co,N-DCP?by hydrothermal method.Pt-CoMoO₄@Co,N-DCP catalysts exhibit excellent MOR activity in alkaline electrolytes due to the efficient electron transport,unique structure and the synergistic effect of bimetallic oxides and Pt nanoparticles.Its mass specific activity reached 4 450 mA mg_Pt^-1,which was about 3 times that of the commercial Pt/C catalyst.In addition,the Pt-CoMoO₄@Co,N-DCP catalyst exhibits significant electrochemical durability compared to commercial Pt/C.The results show that Pt-CoMoO₄@Co,N-DCP catalyst is a promising catalyst for MOR.