A Zinc-Quinone Battery for Paired Hydrogen Peroxide Electrosynthesis

Abstract

Hydrogen peroxide is a commodity chemical with immense applications as an environmentally benign disinfectant for water remediation, a green oxidant for synthetic chemistry and pulp bleaching, an energy carrier molecule and a rocket propellant. It is typically synthesized by indirect batch anthraquinone process, where sequential hydrogenation and oxidation of anthraquinone molecules generates H2O2. This highly energy demanding catalytic sequence necessitates the advent of new reaction pathways with lower energy expenditure. Here we demonstrate a Zn-quinone battery for paired H2O2 electrosynthesis at the three phase boundary of its cathodic half-cell during electric power generation. The catalytic quinone half-cell of the Zn-quinone battery, mediates proton coupled electron transfer with molecular oxygen during its chemical regeneration thereby pairing peroxide electrosynthesis with electricity generation. Hydrogen peroxide synthesizing Zn-quinone battery (HPSB) demonstrated a peak power density of ~90 mW/cm2 at a peak current density of ~145 mA/cm2 while synthesizing ~230 mM of H2O2. HPSB offers immense opportunities as it distinctly couples electric power generation with peroxide electrosynthesis which in-turn transforms energy conversion in batteries truly multifunctional.