Polymerized Riboflavin and Anthraquinone Derivatives for Oxygen Reduction Reaction

Hydrogen peroxide (H2O2) is identified as a promising reagent for fuel cells, reducing the dependency on carbon-based fuels. In this work, electrochemically synthesized polymers are employed to improve the efficiency of the oxygen (O2) reduction reaction, thus producing H2O2 in an environmentally friendly way. Two aminoanthraquinones, as well as riboflavin (vitamin B2), are successfully immobilized via oxidative electropolymerization onto both glassy carbon and carbon paper. Of the investigated compounds, polyriboflavin shows a high Faradaic efficiency toward O2 reduction, even at a very low potential of only -0.1 V versus SHE. This catalytic effect is present in neutral and alkaline conditions, using both glassy carbon and carbon paper, but highly pronounced in neutral, aqueous solutions. Two aminoanthraquinones, as well as riboflavin (vitamin B2), are immobilized via oxidative electropolymerization onto both glassy carbon and carbon paper. Polyriboflavin shows a high Faradaic efficiency toward O2 reduction, even at a low potential of -0.1 V versus SHE. This catalytic effect is present in neutral and alkaline conditions.image