H3PO4 imbibed polyacrylamide-graft-chitosan frameworks for high-temperature proton exchange membranes

• Published in: Journal of power sources 2014-03, Vol.249, p.277-284
• Main Authors: Yuan, Shuangshuang, Tang, Qunwei, He, Benlin, Chen, Haiyan, Li, Qinghua, Ma, Chunqing, Jin, Suyue, Liu, Zhichao
• Format: Article
• Language: English
• Subjects: Applied sciences; Aqueous solutions; Density; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; Imbibition; Membranes; Proton conduction; Synthesis; Three dimensional
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2013.10.104

Proton exchange membrane (PEM), transferring protons from anode to cathode, is a key component in a PEM fuel cell. In the current work, a new class of PEMs are synthesized benefiting from the imbibition behavior of three-dimensional (3D) polyacrylamide-graft-chitosan (PAAm-graft-chitosan) frameworks to H3PO4 aqueous solution. Interconnected 3D framework of PAAm-graft-chitosan provides tremendous space for holding proton-conducting H3PO4. The highest anhydrous proton conductivity of 0.13 S cm-1 at 165 degree C is obtained. A fuel cell using a thick membrane as a PEM showed a peak power density of 405 mW cm-2 with O2 and H2 as the oxidant and fuel, respectively. Results indicate that the interconnected 3D framework provides superhighway for proton conduction. The valued merits on anhydrous proton conductivity, huge H3PO4 loading, and easy synthesis promise the new membranes to be good alternatives as high-temperature PEMs.