Unassisted electrochemical H2O2 production coupled to glycerol oxidation

Abstract

Hydrogen peroxide (H2O2) is not only a key eco-friendly oxidizer but also a promising energy carrier with an energy density comparable to that of compressed hydrogen. The industrial production of H2O2 relies on the energy-intensive and environmentally detrimental anthraquinone process, necessitating the exploration of greener alternatives. Here we demonstrate sustainable and unassisted electrochemical H2O2 production (via the two-electron oxygen reduction reaction) coupled to the oxidative valorization of glycerol, a biomass energy by-product, operating without external electric or solar energy inputs. We applied bismuth-loaded Pt and oxidized carbon nanotube electrocatalysts, for glycerol oxidation reaction and two-electron oxygen reduction reaction, respectively, which possess onset potentials close to the theoretical values for the electrochemical reactions. With this system, we achieved a high H2O2 production rate of approximately 8.475 μmol cm−2 min−1 and high glycerate selectivity for in situ glycerol oxidation reaction (74%), while producing renewable electricity on-site. Hydrogen peroxide (H2O2) is an eco-friendly oxidizer and a promising energy carrier, but it is primarily synthesized through the energy-intensive anthraquinone process. Here sustainable and unassisted electrochemical H2O2 production coupled to glycerol oxidation is reported, operating without an external bias or solar energy input.