Preparation and electrochemical properties of mesoporous NiCoO double-hemisphere used as anode for lithium-ion battery.

NiCoO is a potential anode material for lithium ion battery due to its many advantages, such as high theoretical capacitance, low cost, and good electrochemical activity. In this study, mesoporous NiCoO double-hemisphere (3-5 μm) with high surface area (270.68 m·g) and excellent electrochemical performances has been synthesized through a facile precipitation method followed with thermal treatment process. The prepared NiCoO is pure phase and can be indexed as a face-centered-cubic with a typical spinel structure. Electrochemical tests show the prepared material has high specific capacities (910 mAh·g at 100 mA·g), excellent cyclicity (908  mAh·g at 100 mA·g after 60 cycles) and remarkable high rate performance (after 100 cycles, 585 mAh·g at 400 mAh·g, 415 mAh·g at 800 mAh·g and 320 mAh·g at 1600 mAh·g with coulombic efficiencies of almost 100%). The excellent performances of prepared NiCoO are mainly caused by the unique double-hemisphere structure, which has large surface area, gives material more opportunity to contact with electrolyte and facilitates lithium ion spreading into the material along the radical direction, resulting in a promising application for next-generation lithium-ion batteries.