A Novel Composite Membrane from QPSU and SiO₂ for Solid Alkaline Fuel Cell Applications

Abstract

The goal of this work is to develop a novel composite membrane from quaternized polysulfone (QPSU) and silica (SiO₂), to fabricate alkaline membrane electrode assemblies (MEAs) and to subsequently test the MEAs in 5 cm × 5 cm single cell configuration using Pt/C and Ag/C as anode and cathode catalysts, respectively. The composite membranes were characterized in terms of water absorption, ion exchange capacity and ionic conductivity. The physicochemical studies Fourier transform infra red (FT-IR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) studies, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and universal testing machine (UTM) were used to investigate the relation between the structure and performance of the composite membranes. The results show that the SiO₂ was compatible with the QPSU membrane. The thermal stability and ionic conductivity of the QPSU/SiO₂ composite membranes were higher than that of quaternized polysulfone (QPSU) membrane. The maximum performance was achieved for 10 wt.% SiO₂ with power density of 149.6 mW/cm² at current density of 440 mA/cm².

Keywords:

• Anion exchange membrane
• Silica filler
• Ionic conductivity
• Alkaline membrane fuel cell
• TEM

Additional information

Funding

Financial support from the Department of Science and Technology (DST), New Delhi, India (Letter No. SR/S2/CMP-06/2008, dated 21-08-2008) is gratefully acknowledged.