Preparation and electrochemical properties of mesoporous NiCo₂O₄ double-hemisphere used as anode for lithium-ion battery

NiCo2O4 NiCo₂O₄NiCo₂O₄ 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 NiCo₂O₄ double-hemisphere (3–5 μm) with high surface area (270.68 m²·g⁻¹) and excellent electrochemical performances has been synthesized through a facile precipitation method followed with thermal treatment process. The prepared NiCo₂O₄ 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⁻¹ at 100 mA·g⁻¹), excellent cyclicity (908 mAh·g−1 at 100 mA·g⁻¹ after 60 cycles) and remarkable high rate performance (after 100 cycles, 585 mAh·g−1 at 400 mAh·g⁻¹, 415 mAh·g⁻¹ at 800 mAh·g⁻¹ and 320 mAh·g⁻¹ at 1600 mAh·g⁻¹ with coulombic efficiencies of almost 100%). The excellent performances of prepared NiCo₂O₄ 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.