Synthesis of single-crystalline octahedral LiMn sub(2)O sub(4) as high performance cathode for Li-ion battery

In this paper, we reported the synthesis of single-crystalline octahedral LiMn sub(2)O sub(4) particles by a two-step method in which well-shaped octahedral Mn sub(3)O sub(4) was easily obtained by the hydrothermal reaction of KMnO sub(4) in water/N, N-dimethyl formamide (DMF) mixed solution and then transferred to LiMn sub(2)O sub(4) by the solid-state lithiation process. High crystallinity and phase purity were also observed. When used as a cathode for Li-ion battery, the octahedral LiMn sub(2)O sub(4) particles have demonstrated superior electrochemical properties in comparison with the LiMn sub(2)O sub(4) particles by sol-gel method. A high initial discharge capacity of 122.7 mAh g super(-1) was exhibited at 1C-rate and 104 mAh g super(-1) maintained after 200 cycles for octahedral LiMn sub(2)O sub(4). And good rate capability has also been achieved. The excellent electrochemical properties should be mainly attributed to the special octahedral morphology, single crystalline nature and high crystallinity.