부산대학교 도서관

With well-defined structure and high stability, covalent organic framework (COF) inspires the preparationof new ion-conducting materials for anion exchange membrane (AEM) in alkaline fuel cell. In orderto reveal the influence of micro-nano structure within COF ordered channels on the hydroxide diffusion,we construct a multi-dimensional composite membrane by combining two-dimensional lamellar COFwith one-dimensional polymer chains. The quaternary ammonium-modified COF-LZU1 (QAmCOFLZU1)is incorporated into quaternized poly (2,6-dimethyl-1,4-phenylene oxide) (QAPPO) to fabricateQAmCOF-LZU1/PPO composite membranes. The rapidly diffusion of hydroxide ions in the first solventshell formed by the huge amount of quaternary ammonium groups in the ordered COF channels is investigatedby molecular dynamics simulations. Afterwards, sulfonated graphene oxide (GO) is coated onboth surfaces of the membranes via ionic interactions and p-p interactions to obtain GO@QAmCOFLZU1/PPO sandwich membranes, which would avoid excessive swelling of membranes and leakage ofQA groups. Especially, the GO-sandwiched membrane exhibits strikingly high stabilities and excellentH2/O2 fuel cell performance with a peak power density of 242 mW cm 2 at 60 C. This study providesan effective strategy to construct ion-conducting COF-based composite membranes for highperformancealkaline fuel cell.