Constructing Proton Transfer Channels Using CuO Nanowires and Nanoparticles as Porogens in High-Temperature Proton Exchange Membranes

Constructing proton-transfer channels is considered as an efficient method to improve the performance of cross-linked phosphoric acid (PA)-doped polybenzimidazoles’ membranes. In this study, copper(II) oxide nanowires and nanoparticles are used for the first time as porogens to construct different proton-transfer channels in a high-temperature membrane. Membranes with different porous structures are successfully prepared. The results indicate that the successful construction of continuous porous proton-transfer channel makes positive contributions to improve the performances of a membrane fuel cell. Among them, a continuous proton-transfer channel (continuous pore structure) can be constructed at a lower porogen content using nanowires (which is indicated in the change of conductivity at the ratio of 3:10). Using nanowires also can enable constructing a more effective proton-transfer channel at the same porogen content (at the ratio of 5:10) than using nanoparticles. However, the increase of porogen content is not conducive to the stability of PA retention. The KH560 cross-linked membrane (3:10W-0.01KH560) achieves excellent comprehensive performances. The results indicate that the membranes prepared using nanowires are promising for actual use in high-temperature proton exchange membrane fuel cells.