K-doped Li(2)ZnTi(3)O(8)/C as an efficient anode material with high performance for Li-ion batteries

Li(2)ZnTi(3)O(8)/C and Li(1.9)K(0.1)ZnTi(3)O(8)/C were successfully synthesized using the sol–gel method. Doping K apparently yielded a wider tunnel, helpful for increasing the rate of transport of lithium ions, and furthermore yielded excellent electrochemical properties. The first discharge capacity for Li(1.9)K(0.1)ZnTi(3)O(8)/C was 352.9 mA h g(−1) at a current density of 200 mA g(−1). Li(1.9)K(0.1)ZnTi(3)O(8)/C also performed stably, retaining a capacity of 323.7 mA h g(−1) at the 100th cycle, indicative of its excellent cycling properties. In the rate performance test, Li(1.9)K(0.1)ZnTi(3)O(8)/C showed at the first cycle a high discharge capacity of 379.5 mA h g(−1) for a current density of 50 mA g(−1) and a capacity of 258.9 mA h g(−1) at 1000 mA g(−1). The results indicated that K-doping should be considered a useful method for improving electrochemical performances.