▎ 摘　　要

alpha-Ni(OH)(2) has attracted great attention as a cathode material for alkaline secondary batteries (ASBs) because of its high theoretical capacity and small volume change during charge/discharge cycles. However, poor cycling stability and low electronic conductivity of alpha-Ni(OH)(2) severely hinder its development and practical applications in ASBs. In this work, alpha-Ni(OH)(2)/graphene nanosheet composite was successfully fabricated by a facile homogeneous precipitation method. The nanocomposite is composed of alpha-Ni(OH)(2) nanoflowers decorated homogeneously on the surfaces of graphene nanosheets. When evaluated as cathode material for ASBs, this alpha-Ni(OH)(2)/graphene nanocomposite exhibits much enhanced high-rate capability and cycling stability compared to the pure alpha-Ni(OH)(2) due to the improved electrochemical reaction kinetic, enhanced electronic conductivity, and hierarchical nanostructure. For example, the alpha-Ni(OH)(2)/graphene nanocomposite presents a rate retention of 74.8% as the current density increasing from 250 to 5000 mA g(-1), much higher than that (49.0%) of pure alpha-Ni(OH)(2); moreover, at a current density of 2000 mA g(-1), the alpha-Ni(OH)(2)/graphene nanocomposite still maintains a reversible capacity of 177 mA h g(-1) after 200 cycles, which is four times higher than that (41 mA h g(-1)) of the pure alpha-Ni(OH)(2). The attractive electrochemical performances and facile synthesis route made the prepared alpha-Ni(OH)(2)/graphene nanocomposite become a promising electrode material for ASBs.