Effect of sulfonation degree on the chemical and thermal stability of sulfonated polyether ether ketone (sPEEK) membranes for fuel cell applications

Sulfonated polyether ether ketone (sPEEK) membranes are a group of candidated promising materials for the commercialization of proton exchange membrane fuel cells (PEMFCs). These membranes possess the good mechanical properties, thermal and chemical stability, toughness andsome conductivity, depending on degree of sulfonation (DS). The degree of sulfonation (DS) is a key factor in the desirable properties of the proton exchange membranes in PEM fuel cells. One of the predominant failure modes of PEM fuel cells is the way of degradation in the PEM. In thisstudy, thermal and chemical degradation behavior of sPEEK membranes in various degrees of sulfonation were investigated. The thermogravimetric analysis (TGA) showed that the membrane failure increase with DS in sPEEK membranes as a result of decrease in thermal stability.Moreover, the chemical stability test showed that there is a direct relation between the increase of DS in sPEEK membrans and the decrease of chemical stability

Keywords:

Fuel cell , sPEEK , degree of sulfonation , thermal stability , chemical stability