Fast and Facile Synthesis of LiMn2O4 Nanorods for Li Ion Battery by Microwave Assisted Hydrothermal and Solid State Reaction Methods

A rapid and efficient two-steps growth strategy has been adopted to synthesize monodisperse singlecrystalline spinel LiMn2O4 nanorods. The first step is to synthesize crystalline β-MnO2 nanorods through rapid microwave hydrothermal process followed by second step as solid state reaction between β-MnO2 nanorods and LiOH.H2O to obtain pure spinel LiMn2O4 nanorods. In addition, the possible formation mechanism of the β-MnO2 and spinel LiMn2O4 nanorods was also discussed. The spinel LiMn2O4 nanorods have an average diameter of 190 nm and length of 0.8-1.3 μm. Galvanostatic battery testing shows that the spinel LiMn2O4 nanorods have delivered a stable charge and discharge capacities of 98 and 96 mAhg-1, respectively, after 50 cycles at 0.1C rate in the voltage range 3.1-4.4 V. The cathode material exhibits good electrochemical performance even at high C-rates. The developed LiMn2O4 nanorods show a higher coulombic efficiency and also good rate capability attributed to the formation of the single-crystalline spinel LiMn2O4 with nanorod morphology.