Nanoscale membrane electrode assemblies based on porous anodic alumina for hydrogen-oxygen fuel cell

In this paper, we demonstrate that nanoscale membrane electrode assemblies, functioning in a H-2/O-2 fuel cell, can be fabricated by impregnation of anodic alumina porous membranes with Nafion((R)) and phosphotungstic acid. Porous anodic alumina is potentially a promising material for thin-film micro power sources because of its ability to be manipulated in micro-machining operations. Alumina membranes (Whatman, 50 mu m thick, and pore diameters of 200 nm) impregnated with the proton conductor were characterized by means of scanning electron microscopy, X-ray diffraction, and thermal analysis. The electrochemical characterization of the membrane electrode assemblies was carried out by recording the polarization curves of a hydrogen-oxygen 5 cm(2) fuel cell working at low temperatures (25 divided by 80 degrees C) in humid atmosphere. Our assemblies realized with alumina membranes filled with phosphotungstic acid and Nafion((R)) reach respectively the peak powers of 20 and 4 mW/cm(2) at room temperature using hydrogen and oxygen as fuel and oxidizer.