Self-contained Oxygen Supply for Self-regulating Miniature Fuel Cell

We report a microstructure, which if electrified in a hydrogen peroxide solution covers its top with a thin layer of oxygen gas in a self-regulating manner. In pursuit of realizing a full fuel cell with no moving part, we have successfully developed such an oxygen-generating surface and integrated it as a direct oxygen supply to the cathode of our previously developed miniature fuel cells. The resulting fuel cell showed a significant increase in current density, compared with the previous air-breathing counterpart. This unique oxygen supply takes up a much smaller volume than the existing designs, which require ancillary components, such as a pressurized oxygen tank with a regulator. In designing a fully functional (i.e., self-sustainable) miniature fuel cell, elimination of the need to access the ambient air allows a stackable configuration for higher power demands.