Mildly oxidized and phenol-enriched carbon nanotubes as efficient and selective electrocatalysts for the 2e- oxygen reduction reaction

The electrochemical 2e- oxygen reduction reaction (ORR) represents a green, cost-effective strategy towards hydrogen peroxide (H2O2) production other than a promising and more sustainable alternative to the currently anthraquinone-based technology. Light-weight hetero-doped carbon networks, particularly oxidized systems containing variables O-functionalities, have been deeply investigated as promising and selective metal-free electrocatalysts for the process. Following previous and positive outcomes from our team on the tailored surface engineering of complex C-nanocarbon networks with phenolic dangling groups as effective O-functionalities engaged for the molecular oxygen activation and its selective (2e-) electroreduction, we propose hereafter a facile, scalable and highly reproducible one-pot protocol for the mild and controlled oxidation of multi-walled carbon nanotubes. The as-prepared materials have shown a phenolic enriched surface and a superior ability to foster the almost chemoselective 2e- ORR process already under low overpotential values.