Preparation and Characterization of Phosphoric Acid Doped Polyacrylamide/β-Cyclodextrin High-Temperature Proton Exchange Membrane

The development of high-temperature proton exchange membrane fuel cells calls for better membrane, and a polyacrylamide/beta-cyclodextrin hydrogel proton exchange membrane is prepared by solution polymerization of beta-cyclodextrin (beta-CD) and acrylamide (Am), for which ammonium persulfate (APS) and N, N ''-(methylene)bisacrylamide (MBA) is used as initiator and crosslinking agent, respectively. The observed proton conductivity of the membrane reaches 12.3 S m(-1) at room temperature, when the ratio of beta-CD, APS, MBA to Am monomer is 0.42 mol%, 0.37 mol%, and 0.14 mol%, respectively, and the primary concentration of doped phosphoric acid is 8 mol L-1. The observed proton conductivity evolution on temperature obeys Arrhenius' law, indicating that the proton conduction mainly follows the hopping mechanism. In addition, the prepared PAM/beta-CD proton exchange membrane has a mass loss of only 8.47% at 205 degrees C, showing good thermal stability compared with PBI membrane. It also has good antioxidative stability as well as promising potential application in high-temperature fuel cells.