Influence of the electrolyte content of oxygen carbon gas-diffusion electrodes on their electro-chemical performance in acid solutions

Abstract

Five different methods of Teflon deposition onto the carbon surface were used to study the influence of different electrolyte contents in the carbon gas-diffusion electrodes on their electrochemical performance in acid solution. It was shown that the electrolyte content can be controlled also by the addition of carbon black and by promotion of active carbon with platinum. Electrodes prepared in accordance with these five methods of Teflon deposition differ in electrolyte content over a wide range and therefore the rate of mass transport is considerably influenced especially when the electrodes are working with air. The catalytic activity of pure active carbon is relatively low but the current—voltage characteristics of the electrodes could be positively influenced in the range controlled by the rate of mass transport and ionic conductivity, using a suitable method of Teflon deposition and by the addition of carbon black. The electrochemical performance of electrodes with active carbon promoted with platinum can be improved by the presence of optimum electrolyte content in the electrode using a suitable method of Teflon deposition and the addition of carbon black.