Controllable introduction of edged nitrogen sites in CVD-derived carbon materials for enhanced fenton-like reactions

Nitrogen doped carbon materials have great potential in the peroxymonosulfate based advanced oxidation processes due to their high efficiency. However, because of the limitation of prepared method, the doped N species are usually uncontrollable. In this work, a series of metal-free N-doped carbon materials are synthesized by chemical vapor deposition (CVD) with a CaO template and through regulating the deposition temperature we achieve the gradient control of the edged-N species. Taken phenol as the pollutant probe, the catalytic performances of N-doped carbon material are investigated, and 700 °C is determined to be the optimal deposition temperature for carbon material with a reaction rate constant of 0.335 min −1 . After the analysis of kinetics and the N species, we demonstrate that the content of pyrrolic N has an exponential relationship with the activity. Radicals quenching experiments, electron paramagnetic resonance and electrochemical test are also employed to verify that O 2 •– , 1 O 2 , and direct electron transfer are the dominated reactive oxidation species rather than typic hydroxyl and sulfate radicals. Overall，this doped strategy through CVD give a new insight of controlling doped species in carbon materials preparation.