NiS nanorod-assembled nanoflowers grown on graphene: morphology evolution and Li-ion storage applications

Abstract

This paper reports the morphology, size and phase control of NiS nanoflowers on a graphene substrate. The growth mechanisms of various building blocks for NiS nanoflowers such as nanosheets, nanoflakes, and nanorods are explored under varied experimental conditions. All the obtained NiS nanoflowers were found to be uniformly dispersed on graphene nanosheets, forming a sandwiched nanostructure. When fabricated as an anode material for Li-ion batteries, the graphene supported NiS nanorod-assembled nanoflower shows better cycling performances than pristine NiS and other NiS–graphene composites. It shows a large unprecedented reversible lithium-extraction capacity of 887 mA h g⁻¹ after 60 cycles at 59 mA g⁻¹ and good high-rate capability among NiS-based anodes.