Abstract
[Display omitted]
•Ternary Ni/Co/N co-doped porous carbon film (Ni-Co-N@CF) is fabricated by a simple controllable and scalable strategy.•The Ni-Co-N@CF catalyst exhibits a large electrochemically active surface area and maximum diffusion limited current density.•The catalyst demonstrates a superior anti-poisoning capacity and long-term stability.•The excellent ORR activities are attributed to the synergetic interactions of ternary doping of Ni/Co/N in the film skeleton.•The ternary Ni/Co/N in the film can enhance electron conductivity and provide more Co-N active sites.
Rational design of a stable, highly active non-precious metal-based electrocatalysts for oxygen reduction reaction (ORR) is vitally important for industrial application of fuel cells technology. As a potential alternative of Pt/C catalyst, two-dimensional (2D) porous carbon materials are widely investigated due to the highly accessible surface area and active sites, wherein carbon films doped with a plurality of metals and non-metal elements are rarely reported due to an uncontrollable synthesis process. Here, a bi-metallic (NiCo alloy nanoparticles) and nonmetallic (N) co-doped porous carbon film (Ni-Co-N@CF) is fabricated by a simple controllable and scalable strategy comprising the synthesis of NiCo alloy nanoparticles, modification of organic molecules, and high-temperature carbonization process. The optimized Ni-Co-N@CF catalyst shows an excellent ORR electrocatalytic activity with a larger electrochemically active surface area (2.31 m2 g−1), a higher half-wave potential (0.86 V) and a lower diffusion limited current density (−4.43 mA cm−2) than all the prepared control catalysts. Moreover, the designated catalyst also exhibits high durability and superior methanol tolerance in alkaline media, significantly better than the commercial Pt/C (20 wt%). The superior ORR performance is attributed to the synergetic interactions of ternary doping of Ni/Co/N in the 2D film skeleton, which not only greatly enhances conductivity but also provides more Co-N active sites.