Fabrication of superhydrophilic porous carbon materials through a porogen-free method: Surface and structure modification promoting the two-electron oxygen reduction activity.

Hypothesis: Electrochemical manufacture of HO through the two-electron oxygen reduction reaction (2e ORR), providing prospects of the distributed production of HO in remote regions, is considered a promising alternative to the energy-intensive anthraquinone oxidation process.

Experiments: In this study, one glucose-derived oxygen-enriched porous carbon material (labeled as HGC) is developed through a porogen-free strategy integrating structural and active site modification.

Findings: The superhydrophilic surface and porous structure together promote the mass transfer of reactants and accessibility of active sites in the aqueous reaction, while the abundant CO species (e.g., aldehyde groups) are taken for the main active site to facilitate the 2e ORR catalytic process. Benefiting from the above merits, the obtained HGC possesses superior performance with a selectivity of 92 % and mass activity of 43.6 A g at 0.65 V (vs. RHE). Besides, the HGC can operate steadily for 12 h with the accumulation of HO reaching up to 4090±71 ppm and a Faradic efficiency of 95 %. The HO generated from the electrocatalytic process in 3 h can degrade a variety of organic pollutants (10 ppm) in 4-20 min, displaying the potential in practical applications.