PNNL

Abstract

The development of processes for electrochemical energy conversion and chemical production could benefit from new strategies to interface chemical redox reactions with electrodes. Here, we employ a diffusible low-potential organic redox mediator, 9,10- anthraquinone-2,7-disulfonic acid (AQDS), to promote efficient electrochemical oxidation of H2 at an off-electrode heterogeneous catalyst. This unique approach to integrate chemical and electrochemical redox processes accesses power densities up to 228 mW/cm2 (528 mW/cm2 with iR-correction). These values are significantly higher than those observed in previous mediated electrochemical H2 oxidation methods, including those using enzymes or inorganic mediators. The approach described herein shows how traditional catalytic chemistry can be coupled to electrochemical devices. Financial support for this project was provided by the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. Supplemental funds from the Wisconsin Alumni Research Foundation (WARF) through the WARF Accelerator Program provided partial support for YP and CWA. NMR spectroscopy facilities were partially supported by the NSF (CHE-1048642) and the NIH (S10 OD012245).