Catalysis, Architecture and the Electrochemical Performance of Microfibrous Cathodes for Hydrogen Peroxide Based Fuel Cells

摘要

A novel cathode morphology has been developed for use in magnesium- hydrogen peroxide semi-fuel cells. A direct electrostatic flocking method is used to prepare the carbon microfiber arrays that are subsequently catalyzed with a Pd/Ir alloy by electrochemical deposition. The microfibers protrude from a current collector like the bristles of a brush. Flocking under different voltage field strengths and in various atmospheres is reported upon. A pulse potential deposition technique is compared to the baseline cyclic potential method. XRD data represented to conclude that a homogenous alloy of Pd and Ir is obtained by both techniques. Polarization and constant current results sow these electrodes significantly improve the rate capability of the Mg-hydrogen peroxide cell. Individual electrode potential measurements show that most of the polarization occurs on the cathode. Combinations of Co, W, and Mo with Pd and Ir have been studied to improve catalytic activity. Bipolar electrode fabrication has been accomplished. Long term performance data of single cells and two cell stacks are presented Electrode performance modeling was undertaken.