Preparation and DMFC performance of a sulfophenylated poly(arylene ether ketone) polymer electrolyte membrane

A sulfonated poly(aryl ether ether ketone ketone) (PEEKK) having a well-defined rigid homopolymer-like chemical structure was synthesized from a readily prepared PEEKK by post-sulfonation with concentrated sulfuric acid at room temperature within several hours. The polymer electrolyte membrane (PEM) cast from the resulting polymer exhibited an excellent combination of thermal resistance, oxidative and dimensional stability, low methanol fuel permeability and high proton conductivity. Furthermore, membrane electrode assemblies (MEAs) were successfully fabricated and good direct methanol fuel cell (DMFC) performance was observed. At 2 M MeOH feed, the current density at 0.5 V reached 165 mA/cm, which outperformed our reported similarly structured analogues and MEAs derived from comparative Nafion (R) membranes. (C) 2010 Elsevier Ltd. All rights reserved.Financial support for this project was provided by the National Natural Science Foundation of China (No. 50973040) and the Science and Technology Development Plan of Jilin Province, China (No. 20090322). The work conducted at the Los Alamos National Laboratory was supported by US Department of Energy, Fuel cell technologies. MG acknowledges the support by the WCU (World Class University) program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (R31-2008-000-10092-0)