摘要
A series of proton exchange membranes based on sulfonated polyarylene ether ketones（SPAEKs） was used to study the effect of sulfonation degree on proton conductivity, methanol permeation and performance of direct methanol fuel cells（DMFCs）. Dependences of physical characteristics of the membranes, i. e., proton conductivity, water uptake, swelling ratio, methanol permeability and ion exchange capacity（IEC） were systematically studied. Both methanol permeability and proton conductivity of the SPAEK membrane grow rapidly as the increase in sulfonation degree since methanol molecules and protons share the same transfer channel. However, the methanol permeability plays more important role comparing to proton conductivity. As a result, the SPAEK membrane with a medium sulfonation degree（60%） was found to yield the best performance in a DMFC due to the acquirement of balanced conductivity and methanol permeability.
A series of proton exchange membranes based on sulfonated polyarylene ether ketones（SPAEKs） was used to study the effect of sulfonation degree on proton conductivity, methanol permeation and performance of direct methanol fuel cells（DMFCs）. Dependences of physical characteristics of the membranes, i. e., proton conductivity, water uptake, swelling ratio, methanol permeability and ion exchange capacity（IEC） were systematically studied. Both methanol permeability and proton conductivity of the SPAEK membrane grow rapidly as the increase in sulfonation degree since methanol molecules and protons share the same transfer channel. However, the methanol permeability plays more important role comparing to proton conductivity. As a result, the SPAEK membrane with a medium sulfonation degree（60%） was found to yield the best performance in a DMFC due to the acquirement of balanced conductivity and methanol permeability.
基金
Supported by the National Natural Science Foundation of China（No.21074044）, the National Basic Research Program of China（Nos.2011CB935700, 2012CB215500） and the National High Technology Research and Development Program of China （No .2012AA053401）.
