Nitrogen-Doped Carbon Nanotube-Buffered Fese2 Anodes For Fast-Charging And High-Capacity Lithium Storage

Fast-charging and high-capacity have become indispensable requirements for next-generation energy storage systems. However, large-scale fabrication of high-capacity anode materials for fast Li+ storage remains a huge challenge. Herein, natural hematite is employed as the starting material to achieve scal-able synthesis of nitrogen-doped carbon nanotube-buffered FeSe2 (FeSe2@N-CNT) through a facile cat-alyzing & selenizing process. The readily-available raw materials and simple processing procedures are suitable to industrial-level batch production. In this FeSe2@N-CNT composite, the FeSe2 particles are efficiently encapsulated into the interwoven carbon nanotube network, which can enlarge the contact area with electrolyte, enhance the electrical conductivity, shorten the Li+/e(-) diffusion length and buffer the drastic volume variation of FeSe2 during lithiation/delithiation. As an anode material of lithium ion batteries (LIBs), the FeSe2@N -CNT electrode delivers a significantly high specific capacity of 806 mAh g(-1) at a high current density of 20 A g(-1) (relative to 915 mAh g(-1) at 0.1 A g(-1)). More importantly, long-term cycle stability (953 mAh g(-1) after 1500 cycles at 10 A g(-1)) is achieved, which outperforms most FeSe2-based Li+ storage anodes reported so far. The easy-to-implement mass production and the high Li+ storage property enable FeSe2@N-CNT as a promising candidate as a commercial anode for LIBs. (C) 2021 Elsevier Ltd. All rights reserved.