Facile fabrication of hierarchically porous NiO microspheres as anode materials for lithium ion batteries

Abstract

In this work, we report a novel and facile route for the large-scale fabrication of hierarchically porous NiO microspheres, which involves the thermal decomposition of β-Ni(OH)2 precursor at 450 °C in air for 2 h. The superstructures exhibit high specific surface area, large porous volume, and broad pore size distribution. The electrochemical properties of the hierarchically porous NiO microspheres were examined by cyclic voltammetry and galvanostatic charge/discharge studies. The results demonstrate that the hierarchically porous NiO microspheres are promising anode materials with enhanced lithium storage capacity and excellent cycling stability. The hierarchically porous NiO microspheres can retain a reversible capacity of 612 mA h g−1 after 50 cycles at a current density of 100 mA g−1. The improved electrochemical performance is attributed to their hierarchical structure and large amounts of mesopores within the nanosheets, which can effectively improve structural stability, reduce the diffusion length for lithium ions and electrons, and buffer volume expansion during the charge/discharge processes.