The fluorine-doped and defects engineered carbon nanosheets as advanced electrocatalysts for oxygen electroreduction

Abstract

We present the scalable salt-templated synthesis of two-dimensional porous fluorine-doped carbon (FC) nanosheets. Due to the larger special surface area (1031 m2 g−1) and high active sites, FC-900 (pyrolyzed at 900 °C) shows impressive oxygen reduction reaction (ORR). The synergistic effect of fluoride doping and defects provides richer density of active sites in these nanosheets. When the samples are further calcined at 900 °C for different hours, the ORR activity of the resulting samples shows a little improvement, indicating the influence of the defects on the ORR performance is much inferior to the doped fluorine. The formation of FC structures is beneficial to the ORR activity, and supported by First-principles density functional theory. The results reveal F dopants and defects important role in efficient ORR electrocatalysis owing to the synergistic effect, which is important for comprehending the origin of ORR, and it is also strong evidence to search advanced carbon-based catalysts.