Electrochemical reduction of oxygen to hydrogen peroxide in a gas-diffusion electrode based on mesoporous carbon

Abstract

Mesoporous carbon prepared by template synthesis using SBA-15 mesostructured silicate material was tested as an electrocatalyst for electrochemical synthesis of Н₂О₂ from О₂ in a two-layer gas-diffusion electrode. Preparative syntheses of Н₂О₂ in 0.06 to 2.0 M aqueous solutions of various electrolytes (pH 2–8) were performed at current densities in the interval 0.05–0.19 A cm^–2. Solutions with an Н₂О₂ concentration of 1–2.8 M were prepared with 46–70% current efficiency. Thus, the material tested shows promise as an electrocatalyst of two-electron reduction of oxygen to Н₂О₂.