Facile synthesis of single-crystal mesoporous CoNiO₂ nanosheets assembled flowers as anode materials for lithium-ion batteries

Mesoporous CoNiO₂ microflowers assembled with single-crystal nanosheets were successfully synthesized by a hydrothermal method and subsequent annealing process and their lithium storage capacity were investigated. The structural and compositional analysis of the mesoporous CoNiO₂ microflowers has been studied by X-ray diffraction, field emission scanning electron microscopy and high-resolution transmission electron microscopy. The Bruauer-Emmett-Teller specific surface area of CoNiO₂ microflowers has been calculated by the nitrogen isotherm curve and pore size distribution has been determined by the Barret-Joyner-Halenda method. It has been found that the as-prepared CoNiO₂ electrodes delivered satisfied capacity, good cycling stability and rate capability. The improved electrochemical performance is attributed to the mesoporous nature and the 3D assembled structure. Therefore, such a structure can be considered to be an attractive candidate as an electrode material for lithium-ion batteries. © 2014 Elsevier Ltd.