H3PO4-imbibed three-dimensional polyacrylamide/polyacrylamide hydrogel as a high-temperature proton exchange membrane with excellent acid retention

We herein report the use of polyacrylamide/polyacrylamide interpenetrating polymer network (PAM/PAM IPN) hydrogel as a matrix to imbibe proton conducting H3PO4, forming a robust proton exchange membrane (PEM) suitable for high-temperature PEM fuel cells by combining excellent acid retention, simple synthesis, and low cost. Its extraordinary ability to absorb large quantity of aqueous solution is fully utilized to achieve high H3PO4 loading, showing a proton conductivity of 0.0833 S cm(-1) at 183 degrees C in dry air. The synthesized membrane also shows excellent acid retention even under mechanical load and high humidity. These profound advantages along with simple and low-cost synthesis promise the new membrane to be a strong candidate as a high-temperature PEM.