Cathodic H 2 gas production through Pd alloy membrane electrodes

Abstract

The object of this study was to develop a high performance hydrogen-metal oxide cell. A hydrogen permeable membrane electrode (HPME)-H 2-NiOOH rechargeable cell was tested for this purpose and the performance of the cathodic hydrogen gas production through the membrane electrode was investigated. A Pd 66.6 wt%-Ag 13.4 wt%-Au 20 wt% alloy membrane electrode, of which one surface was covered with PdPt black catalyst and the other with Pd black, was used to make one of the walls of the hydrogen gas containing vessel. When the PdPt catalysed electrolyte-facing surface is cathodically polarized in concentrated KOH solutions, hydrogen atoms dissolve in the membrane by penetrating it and leave the other palladized surface as free hydrogen gas, which passes into the gas chamber. The influence of electrode potential, hydrogen pressure in the gas chamber, membrane thickness, electrolyte concentration and temperature on the hydrogen production rate and yield into the gas chamber was investigated and a refined analysis on the said phenomena was carried out.