Ternary doped porous carbon nanofibers with excellent ORR and OER performance for zinc-air batteries

The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) play an important role in the air electrode reactions of rechargeable Zn-air batteries. However, noble metal-based catalysts for the ORR and OER always suffer from high cost and poor stability. Carbon-based materials with many advantages such as low cost, good conductivity, a large specific surface area and considerable durability are considered as promising alternatives to noble metal-based catalysts. In particular, the doping of heteroatoms into carbon has been proven to be an effective method to improve catalytic performance. Herein, we synthesized N, F, P ternary doped macro-porous carbon fibers (NFPC) as a bifunctional catalyst for primary and rechargeable Zn-air batteries for the first time via an electrospinning method with subsequent thermal annealing. The uniform distribution of heteroatoms in the macroporous carbon fibers induced a greatly improved catalytic efficiency towards the ORR and OER, showing exceptional properties in Zn-air systems.