Influence of Solution pH on Pt Anode Catalyst in Direct Formic Acid Fuel Cells

Abstract

Formic acid has great potential for use as fuel in direct formic acid fuel cells (DFAFC). Because the catalytic activity of Pt for formate oxidation is sluggish in alkaline media, researchers have focused on using acid media in DFAFC technology. Recently, Osawa's group demonstrated that the best reaction performance can be achieved at pH approximate to pK(a). A systematic investigation of the HCOOH/HCOO- oxidation in an actual single cell over a wide pH range has not yet been performed. Here, single-cell experiments confirm the direct formate pathway in HCOOH/HCOO- oxidation, which leads to better oxidation kinetics at the optimal pH.