Recent progress of electrospun porous carbon-based nanofibers for oxygen electrocatalysis

Oxygen electrocatalysis including oxygen reduction reaction and oxygen evolution reaction is key to improve conversion efficiency of metal–air batteries. Noble metals are accepted for oxygen electrocatalysis, but their scarcity and poor durability largely inhibit their wide commercial application. One-dimensional (1D) porous carbon-based materials (e.g. carbon-supported transition metals and heteroatom-doped carbon) are the promising alternatives for noble metal–based catalysts, owing to more exposed active sites, high electronic conductivity, and good mechanical strength. However, achieving favorable 1D porous carbon-based materials remains a great challenge. Electrospinning technology accompanied by post-treatments (e.g. preoxidation and annealing) is considered to be a facile and universal strategy for the preparation of porous carbon-based nanofibers. This review focuses on recent progress in designing of porous carbon-based nanofibers via electrospinning technology for oxygen electrocatalysis. A brief introduction of the electrospinning principles is provided and discussed firstly. Then, a classified introduction and discussion of electrospun porous carbon-based nanofibers in terms of preparation and application in oxygen electrocatalysis is highlighted. Finally, the current challenges and future perspectives on the synthesis and electrocatalytic applications of electrospun porous carbon-based nanofibers are proposed.