Rational design of Fe-doped K0.8Ti1.73Li0.27O4@rGO as a high-rate and long-cycle-life anode for lithium-ion batteries

K0.8Ti1.73Li0.27O4 (KLTO) is an important titanium-based anode material for lithium-ion batteries (LIBs) and is expected to become an alternative to carbonaceous materials on account of its nontoxicity, low cost, and high safety performance. However, it suffers from poor specific capacity at high charge–discharge rates due to its low conductivity and obstructed Li-ion diffusion. In this work, an Fe-doped KLTO@rGO (Fe-KLTO@rGO) composite prepared by following a simple electrostatic assembly process and its high-rate and long-cycle-life-performance as an anode in LIBs is obtained. The Fe-KLTO@rGO composite sample has an excellent specific capacity of 330 and 105 mAh g−1 at a current density of 1 C (1 C = 175 mA g−1) and 50 C, respectively. In addition, the Fe-KLTO@rGO composite sample can carry out a long cycle of 3000 cycles at a rate of 50 C, and the specific capacity remains at 127 mAh g−1.