Porous platinum electrodes derived from the reduction of sputtered platinum dioxide films

Abstract

The present study was undertaken to establish whether highly porous platinum dioxide ®lms deposited by reactive sputtering of platinum in an oxygen plasma could serve as precursor to high speci®c surface area electrodes of platinum. The chemistry underlying such process is quite simple and has as its precedent the wide use of platinum dioxide, also known as Adams' catalyst, as the precursor of ®nely divided metallic platinum in the hydrogenation of organic compounds [1]. Metallic electrodes with high speci®c surface areas may be advantageously incorporated in batteries, fuel cells and sensors [2±4] because of considerations such as ef®ciency and the ultimate size of the device. High surface area electrodes may be prepared by controlling electrodeposition parameters [5] or as described by Attard et al. [2] through the use of the ordered pore structure of a lyotropic liquid crystalline phase. Additional methods include thermal decomposition of a precursor [6] or through sputtering [7]. The latter method provides a great deal of exibility since complex targets may be sputtered and also the chemistry of the process may be modi®ed through the participation of a reactive plasma medium [8].