TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The catalyst further comprises at least one of platinum, gold, ruthenium, rhodium, osmium, iridium, silver, nickel, copper, cobalt, iron, chromium, lead, vanadium or tungsten; Pd, PdPt, PdAu, PdPtRu, PdPtIr, PdPtAu, PdPtRuIr, PdPtRuOs or PdPtRuIrOs. The ion-exchange electrolyte is a cation exchange electrolyte.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The catalyst further comprises at least one of platinum, gold, ruthenium, rhodium, osmium, iridium, silver, nickel, copper, cobalt, iron, chromium, lead, vanadium or tungsten; Pd, PdPt, PdAu, PdPtRu, PdPtIr, PdPtAu, PdPtRuIr, PdPtRuOs or PdPtRuIrOs. The ion-exchange electrolyte is a cation exchange electrolyte. EXAMPLE - An electroplating mixture contained (NH4)2PdCl4 (12 wt.%), octaethylene glycol monohexadecyl ether (C16EO8) (47 wt.%), heptane (2 wt.%) and deionized water (39 wt.%). The mixture was subjected to three heating-cooling cycles (temperature limits 20 and 80degreesC) with vigorous shaking using a vortex mixer until a homogeneous mixture was formed. The mixture was then allowed to stand at room temperature overnight. A conventional three-electrode system using a large-area platinum counterelectrode together with a saturated silver/silver chloride (Ag/AgCl) was used to perform the electrodeposition. Mesoporous palladium films were produced by electrochemical deposition from the electroplating mixture at +0.16 V vs Ag/AgCl onto a gold film. The thickness of the palladium films were controlled by recording the total charge passed during deposition. Typical deposition charge was 20 C cm-2. Following deposition, the palladium films were rinsed repeatedly in acetone and deionized water to remove impurities (surfactant, electrolyte and organic solvents). Low resolution SEM images of the film deposited on a gold foil showed a smooth, dense and uniform surface. High resolution SEM image exhibited uniform morphology characteristic of leaf-like laminae. A conductive electrode with an electrodeposited mesoporous palladium was pressed into direct contact with a Nafion (RTM; exchange membrane). Utilization of a small amount of soluble Nafion solution on the electrode surface before the interface was formed followed by curing at 120degreesC aids which was the long-term stability of the interface. The activity of the catalyst system was carried and the rate of methanol oxidation was found to be so high on the plateau which was evident in slow-scan voltammograms at 2 mV s-1 and strongly suggested that the electrode reaction was diffusion controlled at high overpotential. Thus the significant enhancement in catalytic activity was seen when mesoporous palladium which was used in contact with a solid polymer electrolyte.