Journal of Colloid and Interface Science, Vol.564, 276-285, 2020
Template synthesis of two-dimensional ternary nickel-cobalt-nitrogen co-doped porous carbon film: Promoting the conductivity and more active sites for oxygen reduction
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 m(2) 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. (C) 2019 Elsevier Inc. All rights reserved.
Keywords:Ternary doping;2D porous carbon film;Oxygen reduction reaction;Synergistic interaction;Electrocatalysts