Hierarchically ordered porous nickel oxide array film with enhanced electrochemical properties for lithium ion batteries

Hierarchically ordered porous nickel oxide array film was prepared by electrodeposition through monolayer polystyrene spheres template. The as-prepared film had a highly porous structure of interconnected macrobowls array possessing nanopores. As anode material for lithium ion batteries, the porous array NiO film exhibited weaker polarization, higher coulombic efficiency and better cycling performance in comparison with the dense NiO film. After 50 cycles, the discharge capacity of porous array NiO film was 518 mAh g− 1 at 1 C rate, higher than that of the dense NiO film (287 mAh g− 1). The enhancement of the electrochemical properties was due to the unique hierarchical porous architecture, which provided fast ion/electron transfer and alleviated the structure degradation during the cycling process.