Pyranoid-O-dominated graphene-like nanocarbon for two-electron oxygen reduction reaction

Exploring the high-efficient two-electron oxygen reduction reaction (2e- ORR) catalysts is greatly significant for promoting hydrogen peroxide (H2O2) electroproduction. Herein, we have constructed a pyranoid-O-dominated graphene-like nanocarbon (GLC) material with high surface area, hierarchical porous structure, and abundant edge defects, through the high-temperature alkali activation of cellulose-based precursor. Benefiting from its integrated merits, the GLC electrocatalyst exhibits excellent 2e- ORR performance with high H2O2 productivity and ultrafast wastewater degradation ability. Interestingly, whether changing the carbonaceous precursor or alkali activator, all the as-prepared pyranoid-O-dominated GLC-based materials display high 2e- selectivity for the ORR. Based on further analogical experiments and theoretical analysis, the results reveal that the nature of 2e- selectivity on carbon-based materials is highly associated with the pyranoid-O dopants, rather than the surface oxygen-containing functional groups declared by the previous reports. These findings may bring new insight into the 2e- ORR selectivity of carbon-based electrocatalysts for H2O2 production.