Proliferating Oxygen Reduction Reaction by High Volume of Mesopores in Regular Nickel–Nitrogen Codoped Carbon Nanocubes

Abstract

AbstractTheoretically, nickel–nitrogen codoped carbon (Ni–N/C) is a promising oxygen reduction reaction (ORR) catalyst. However, precisely controllable synthesis of Ni–N/C nanostructures with large surface area and high volume of mesopores remains insurmountable challenge. In this work, a mesoporous nickel–nitrogen codoped carbon nanocube (denoted as Ni–N/C‐NCs) catalyst with high specific surface area of 1085 m2 g−1 is illustrated. The high volume of mesopores is confirmed to not only allow the great exposure of highly active C‐N site, but also facilitates the mass transfer and gas diffusion, resulting in promotion of ORR activity and kinetics. In 0.1 m KOH, a diffusion‐limited current density of 6.61 mA cm−2 is achieved, which is 20% higher than that of commercial 20 wt% Pt/C and superior to most catalysts reported to date. The Ni–N/C‐NCs prepared by the new synthetic route not only show excellent ORR performance, but also exhibit high structural thermostability, which makes it a promising catalyst for industrial applications.