Proton Transport in Aluminum-Substituted Mesoporous Silica Channel-Embedded High-Temperature Anhydrous Proton-Exchange Membrane Fuel Cells.

ABSTRACT: Polymer composite membrane technology is promising for enhancing the performance of membrane electrode assemblies for high-temperature fuel cells. In this study, we developed a novel anhydrous proton-exchange polybenzimidazole (m-PBI) composite membrane using Al-substituted mesoporous silica (Al-MCM-41) as a proton-carrier support. The surface-substituted Al-MCM-41 formed effective proton-transport pathways via its periodic hexagonal channel and improved the proton conductivity. The proton conductivity of an m-PBI filled with 9 wt.% filler was 0.356?S?cm^-1 at 160?°C and 0% humidity, representing an increase of 342% compared to that of a pristine m-PBI. Further, the current density at 0.6?V and maximum power density of m-PBI composite membranes were increased to 0.393?A?cm^-2 and 0.516?W?cm^-2, respectively. The enhanced fuel-cell performance was attributed to the proton-transfer channels and H₃PO₄ reservoirs formed by the mesopores of the Al-MCM-41 shell. The results indicated that Al-MCM-41 is suitable with respect to the hybrid homologues for enhancing the proton transport of the m-PBI membrane.

SUBMITTER: Seo K 

PROVIDER: S-EPMC7316861 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature