Oxygen and nitrogen co-doped ordered mesoporous carbon materials enhanced the electrochemical selectivity of O2
Meichun Qin1, Shiying Fan1, Liang Wang1
1State Key Laboratory of Fine Chemicals, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
Abstract:
Electrochemical hydrogen peroxide production from two-electron oxygen reduction reaction, a cost-effective, sustainable and reliable method compared with the traditional anthraquinone process, is attracting growing attention. However, it is challenged by the selectivity of electrocatalysts. In this context, nitrogen and oxygen co-doped ordered mesoporous carbon materials have been successfully fabricated. Benefiting from the ordered pore structure, better dispersion behavior and valid doping effect, a high selectivity (~95.00%), good activity and stability toward H2O2 production were achieved. Systematic characterizations like physical adsorption, zeta potential, X-ray photoelectron spectroscopy and density functional theory (DFT) calculation revealed that interactive effects between pyridinic N and functional groups of COOH/COC largely facilitated the desorption of intermediates (*OOH, * represents an unoccupied active site) in turn enhance the selectivity of electrocatalysts toward H2O2 production. Interestingly, H2O2 produced in situ was applied to Electro-Fenton, the formaldehyde mineralization rate was high to about 88.06%. These findings offer a rational chemical design of electrocatalysts toward H2O2 production and pollutant purification.


