A facile N doping strategy to prepare mass-produced pyrrolic N-enriched carbon fibers with enhanced lithium storage properties

Abstract

Carbon-based nanomaterials with suitable morphology, structure and composition are promising candidates for lithium-ion battery (LIB) anode materials. In this work, the chemical vapor deposition technique followed by a facile gas-solid phase doping strategy is exploited to prepare mass-produced pyrrolic N-enriched carbon fibers (PN-CFs). The effect of N doping on the morphology, structure, composition and LIB performance of PN-CFs is investigated. The results show that intrinsic structure defects existing in raw carbon fibers act as active sites for effective N doping. The obtained PN-CFs possess unique spiral nanofiber morphology, high defect degree and dominated pyrrolic N (∼96% for the total doped N), which result in super-long cycling lifespan (370.9 mAh g−1 at 5 A g−1 after 1000 cycles) and superior high-rate capability (171.1 mAh g−1 at 20 A g−1) when used as LIB anode material.