Synergistic Amplification of Water Oxidation Catalysis on Pt by a Thin-Film Conducting Polymer Composite

Abstract

Despite their potential for facilitating high activity, thin-film conducting polymer supports have, historically, expedited only relatively weak performances in catalytic water oxidation (with current densities in the μA/cm2 range). In this work, we have investigated the conditions under which thin-film conducting polymers may synergistically amplify catalysis. A composite conducting polymer film has been developed that, when overcoated on a bare Pt electrode, amplifies its catalytic performance by an order of magnitude (into the mA/cm2 range). When poised at 0.80 V (vs Ag/AgCl) at pH 12, a control, bare Pt electrode yielded a current density of 0.15 mA/cm2 for catalytic water oxidation. When then overcoated with a composite poly(3,4-ethylenedioxythiophene) (PEDOT) film containing nanoparticulate Ni (nano-Ni) catalyst and reduced graphene oxide (rGO) conductor in the specific molar ratio of 4.5 (C; PEDOT): 1 (Ni): 9.5 (C; other), the electrode generated water oxidation current densities of 1.10–1.15 mA/cm...