Wettability-modulated ordered mesoporous carbon electrodes for electrocatalytic reactions involving gases

Abstract

Herein, a series of ordered mesoporous carbon (OMC) electrodes with switchable surface wettability were developed. These electrodes are favorable for water electrolysis at high current densities and increase the production of H2O2 in the oxygen reduction reaction. The hydrophilic OMC electrodes can promote the oxygen evolution reaction performance by separating O2 bubbles promptly. The hydrophobic OMC electrodes provide a directional diffusion channel for O2 transport to improve the efficiency of O2 utilization. The hydrophobic OMC electrode is used for green synthesis of H2O2 with a production rate of 48.1 mmol gcat−1 h−1, Faraday efficiency of 86.3%, and minimum energy consumption of 3.07 kWh kg−1. The constructed electro-Fenton system reached 87% and 73% removal rate of rhodamine B and methyl orange within 60 min, respectively. The hydrophilic/hydrophobic electrodes are expected to have an important function in electrocatalytic reactions involving gases.