Hydrogen sorption properties of Pd nanoparticles dispersed on graphitic carbon studied with a cavity microelectrode

The hydrogen sorption properties of nanosized palladium particles dispersed in high surface area graphite powders are studied by both solid/gas and electrochemical methods. Using either classical powder electrodes or a cavity microelectrode we show that cyclic voltammetry peaks coming from the hydrogen sorption/evolution, that are usually strongly overlapped in powder electrodes, can be resolved at low scan rates. With the cavity microelectrode, we could measure voltammograms over a 3-decade range of potential scan rates and thus describe the sorption processes in this hybrid material.