Inorganic Electrolyte Membrane for High-temperature PEM fuel cell: Conception, Preparation and Performance

Abstract

A novel conception of inorganic proton exchange membrane for elevated temperature PEM fuel cell was proposed in this research. The inorganic electrolyte was approached by trapping heteropolyacid (HPA) molecules inside mesoporous silica structure via a self-assembly route assisted with a structure-directing surfactant, and then construct an inorganic membrane based on mesoporous silica matrix and HPA proton conducting sites. Such mesoporous HPA/silica significantly enhance the stability of HPA molecules, and provided continuous proton transfer channels with diameter of 3~4 nm, resulting high proton conductivity of about 0.05 S/cm at 300°C. A PEMFC based on the mesoporous HPA/silica inorganic PEM and a non-platinum cathode catalyst achieved a power density of 102 mW/cm² at 300°C, closing to the performance of the cell with Pt catalyst at temperature of 80 °C.

Key findings

• ▸Proton conductivity of 0.05 S/cm at 300°C was achieved using mesoporous HPA/silica inorganic PEM.
• ▸A PEMFC with non-platinum cathode catalyst achieved 102 mW/cm² at 300°C, comparable to Pt catalyst at 80°C.
• ▸Mesoporous HPA/silica structure enhances stability of HPA molecules and provides continuous proton transfer channels.

Keywords

Identifiers

DOI

10.1149/1.2981908

Journal

ECS Transactions

Year

2008