Rational design of FeTiO3/C hybrid nanotubes: promising lithium ion anode with enhanced capacity and cycling performance

Abstract

Ilmenite FeTiO₃ has the advantage of high theoretical capacity and abundant sources as an anode material for lithium-ion batteries (LIBs). However, it suffers inferior rate capability caused by the aggregation of particles. To solve this problem, FeTiO₃ nanoparticles embedded in porous CNTs were developed by the sol–gel route and subsequent calcination. The unique hybrids have a uniform distribution of FeTiO₃ nanoparticles (5–20 nm) in the carbon matrix. Electrochemical tests prove that the porous FeTiO₃/C hybrid nanotubes deliver a high capacity of 612.5 mA h g⁻¹ at 0.2 A g⁻¹ after 300 cycles. Moreover, they present remarkable rate capability and exceptional cycling stability, possessing 163.8 mA h g⁻¹ at 5 A g⁻¹ for 1000 cycles. The enhanced electrochemical performance of the FeTiO₃/C hybrid is derived from the shortened Li⁺ transport length, good structure stability and conductive carbon matrix, which simultaneously solves the major problems of pulverization and agglomeration of FeTiO₃ nanoparticles during cycling.