Electrochemical growth of gold nanostructures on carbon paper for alkaline direct glucosefuel cell

Abstract

Au nanocorals and nanoparticles were grown on carbon papers via a simple two-electrode electrochemical deposition process by reducing HAuCl₄ under constant potentials in mixtures containing cetyltrimethylammonium chloride (CTAC) and/or NaNO₃. Electrochemical characterizations showed that the nanocoral electrode exhibited high surface area and high electrocatalytic activity towards glucose oxidation in alkaline media. These Au nanostructures were employed as anodes and assembled with anion exchange membranes and Pt cathodes for alkaline direct glucose fuel cell (DGFC) investigations. Open-circuit voltages (OCVs) of the Au nanocoral and nanoparticle electrodes were 0.64 V and 0.61 V, and their maximum power densities were 0.847 mW cm⁻² and 0.336 mW cm⁻², respectively. The cells showed stable output over 5 h with a small decrease in OCV (6.9%). The electrodes could be refreshed after electrochemical reduction steps.