Soft doping of phosphorus into cobalt nanoparticle-embedded nestlike nitrogen-rich carbon nanotube clusters for efficient oxygen reduction

Low-temperature plasma glowing on solid materials has proven to be effective for surface engineering. Plasma treatment can alter their surface structure and composition but causes negligible damage to the main framework under a proper condition. In this work, we achieved phosphorus (P) doping into nestlike clusters of nitrogen-rich carbon nanotubes embedded with cobalt nanoparticles (CoNCnc) using microwave plasma in the presence of a stable and nontoxic salt, NaH 2 PO 4 , to enhance the catalytic efficiency of oxygen reduction reactions (ORR). The results indicate that P was successfully implanted onto the surface of CoNCnc through microwave plasma irradiation. The nestlike structure and cobalt nanoparticles (Co NPs) distribution were barely affected by the plasma treatment, while its ORR catalytic activity was significantly enhanced with excellent durability and methanol tolerance. Due to the high efficiency and low energy consumption of microwave plasma, the proposed doping strategy can be a potential way for boosting the performance of earth-abundant elements based electrocatalysts.