Rational design of hierarchical Ni embedded NiO hybrid nanospheres for high-performance lithium-ion batteries

Abstract

Novel hierarchical Ni/NiO hybrid nanospheres were fabricated by a simple solvothermal synthesis method followed by thermal oxidation. The hybrid nanospheres are uniform-sized and composed of tiny Ni embedded NiO nanoparticles. Galvanostatic battery tests show that the corresponding electrode can deliver a high reversible capacity of 712 mA h g⁻¹ for the second discharge and a capacity of 825 mA h g⁻¹ was obtained after 132 cycles at a rate of 0.2C. Good rate performance was achieved even when the rate is as high as 12C with a high capacity of 453 mA h g⁻¹, and a capacity of 800 mA h g⁻¹ was retained when it returned to 0.2C after 300 cycles. The excellent cycling stability and rate performance are derived from the special nanostructural characteristics of the prepared hybrid nanospheres, indicating that they are a promising anode material for high-performance lithium-ion batteries.