Miniature 250 mu m thick fuel cell with monolithically fabricated silicon electrodes

A fabrication technique of miniature fuel cell electrodes was developed from Si wafers. The fuel channels, porous layer, and catalyst layer were formed in the Si wafer. The fuel channels were fabricated by photolithographic patterning and subsequent wet etching on the Si. The porous layer was formed by anodization of Si from the polymer electrolyte membrane side through the bottom of the fuel channels. Catalyst metals were deposited inside the porous layer by wet plating. The two electrodes were hot-pressed with a Nafion 112 sheet. Open-circuit voltage of 840 mV and maximum power density of 1.5 mW/cm(2) were observed by hydrogen feed. (C) 2004 The Electrochemical Society.