The Dmfc With Enhanced Proton Exchange Membrane Research

Proton exchange membrane,as one of the key component material of direct methanol fuel cells(DMFC),which plays the critical role of separating the anode and cathode side of DMFC and transferring the hydrated proton,etc.,has been attracting more and more attentions. Although the commercialized Perfluoromembranes,such as Nafion,have been successfully applied in the hydrogen proton exchange membrane fuel cells,their high methanol penetrating coefficient and higher cost make them limited to be used in Direct Methanol Fuel Cell(DMFC).In order to overcome the deficiencies of Nafion membranes,two ways were adoped to resolve this problems,which include Porous-PTFE reinforced and through sol-gel processes with co-hydrolysis to synthesize.(1)The ABPSH40/PTFE composite membranes were prepared by impregnating ABPSH40 resin into the porous PTFE substrate membrane that with surface modification.The microstructures of composite membranes were studied by SEM.The methanol permeabilities were investigated by GC as well as the proton conductivity of membranes by AC impedance.The results indicated that ABPSH40 resin was well plugged into the micropores of PTFE.The dimensional stability and mechanical strength of the composite membranes were apparently improved.The composite membranes had lower methanol permeability and similar proton conductivity compared with Nafion^?115 membrane.(2)NaBH₄ was used as the reducing agent to change the carbonyl group of SPEEK into the hydroxyl group.A series of organic/inorganic composite materials based on SPEEK/SiO₂ to be used as electrolytic membrane in direct methanol fuel cell(DMFC) have been synthesized through sol-gel processes which include graft and Co-hydrolysis.The chemical reaction of the hybrid membrane was investigated by FT-IR spectroscopy.The composite behavior was studied by a scanning electronic microscope.The proton conductivity was determined using an AC impedance analyzer.The methanol permeation coefficient was determined using gas chromatography.The results indicated that dimensional stabilities increase with the ratio of SiO₂,The composite membrane had lower methanol permeability and similar proton conductivity compared with Nafion^?115 membrane.