Facile synthesis of loaf-like ZnMn₂O₄ nanorods and their excellent performance in Li-ion batteries.

Binary transition metal oxides have been attracting extensive attention as promising anode materials for lithium-ion batteries, due to their high theoretical specific capacity, superior rate performance and good cycling stability. Here, loaf-like ZnMn2O4 nanorods with diameters of 80-150 nm and lengths of several micrometers are successfully synthesized by annealing MnOOH nanorods and Zn(OH)2 powders at 700 °C for 2 h. The electrochemical properties of the loaf-like ZnMn2O4 nanorods as an anode material are investigated in terms of their reversible capacity, and cycling performance for lithium ion batteries. The loaf-like ZnMn2O4 nanorods exhibit a reversible capacity of 517 mA h g(-1) at a current density of 500 mA g(-1) after 100 cycles. The reversible capacity of the nanorods still could be kept at 457 mA h g(-1) even at 1000 mA g(-1). The improved electrochemical performance can be ascribed to the one-dimensional shape and the porous structure of the loaf-like ZnMn2O4 nanorods, which offers the electrode convenient electron transport pathways and sufficient void spaces to tolerate the volume change during the Li(+) intercalation. These results suggest the promising potential of the loaf-like ZnMn2O4 nanorods in lithium-ion batteries.