Abstract
A supported thin palladium membrane was fabricated using electroplating coexisting with supercritical carbon
dioxide, named supercritical electroplating. In this unique electroplating, immediate dissolution of hydrogen formed
via water electrolysis into supercritical carbon dioxide as well as fabrication of a dense metallic film consisting of
nano-size crystals will be expected by dispersion of conductive plating solution into inconductive supercritical carbon
dioxide. Commercially available palladium plating baths, however, cannot be applied to supercritical electroplating
aqueous solution with acidic property, because they were developed to extend the service life by the formation of stable palladium complex in ammonium aqueous solution with basic property. In this study, a new bath composed of
PdCl2, KBr, KNO2, H3BO3, Glycine and surfactant was developed for the supercritical palladium plating. As a result,
a defect-free palladium film could be fabricated on a porous conductive support.
