NiCo Alloy Nanoparticles Decorated on N-Doped Carbon Nanofibers as Highly Active and Durable Oxygen Electrocatalyst

The exploring of catalysts with high-efficiency and low-cost for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is one of the key issues for many renewable energy systems including fuel cells, metal-air batteries, and water splitting. Despite several decades pursuing, bifunctional oxygen catalysts with high catalytic performance at low-cost, especially the one that could be easily scaled up for mass production are still missing and highly desired. Herein, a hybrid catalyst with NiCo alloy nanoparticles decorated on N-doped carbon nanofibers is synthesized by a facile electrospinning method and postcalcination treatment. The hybrid catalyst NiCo@N-C2 exhibits outstanding ORR and OER catalytic performances, which is even surprisingly superior to the commercial Pt/C and RuO2 catalysts, respectively. The synergetic effects between alloy nanoparticles and the N-doped carbon fiber are considered as the main contributions for the excellent catalytic activities, which include decreasing the intrinsic and charge transfer resistances, increasing C=C, graphitic-N/pyridinic-N contents in the hybrid catalyst. This work opens up a new way to fabricate high-efficient, low-cost oxygen catalysts with high production.