S, N co-doped pitch-based composite carbon nanofibers with enlarged interlayer distance as a superior potassium ion batteries anode

Abstract

Potassium ion batteries (PIBs), an alternative to traditional lithium ion batteries to large-scale energy storage device, have attracted tremendous attention, due to abundant reserves of potassium resources and low cost. However, it still remains challenge to fabricate suitable anode materials with high K storage capabilities. In this work, facile S/N co-doped pitch based composite carbon nanofibers has been fabricated by electrospinning of coal tar pitch and polyacrylonitrile, and followed by carbonization under H2S/Ar atmosphere. The formation of -C-S-Cbond effectively increased S utilization, and enlarged carbon interlayer distance to some degree. As anode for PIBs, the S/N co-doped carbon displayed enhancement of capacity, rate capability and cycle stability. This work would shed a light on the fabrication of S/N co-doped materials for both battery, supercapacitor and electrocatalytic electrodes.