Three-dimensional porous Co3O4 hexagonal plates grown on nickel foam as a high-capacity anode material for lithium-ion batteries

Abstract Three-dimensional (3D) hierarchical hexagonal plate-like Co3O4 microstructure arrays were directly synthesized on nickel (Ni) foam via a simple solvothermal process and consequent annealing treatment. The NH4F was employed as a template in the preparation of hexagonal plate-like Co3O4 microstructure arrays. The 3D hexagonal plate-like Co3O4 microstructure synthesized at 140 °C (Co3O4@NF-140) exhibited better morphology and higher energy storage performance compared to the samples obtained at 160 °C (Co3O4@NF-160) and 180 °C (Co3O4@NF-180). Remarkably, as-synthesized materials were used as an anode material for lithium-ion batteries and the optimized electrode (Co3O4@NF-140) exhibited superior charge storage performance, i.e., noteworthy rate capability and good cycling performance. The outstanding capacity values of 500 and 390 mA h g-1 were obtained at 1 and 2 A g-1, respectively over 500 cycles. The specific capacity of the optimized electrode (Co3O4@NF-140) could also retain the 606 mA h g-1 at 500 mA g-1 after 100 cycles with less capacity fading and also exhibited excellent rate performance. The superior performance is ascribed to the proficient charge transportation from the 3D hierarchical Co3O4 microstructures to the substrate, improved solid interface with the current collector, and strongly adhered microstructures related to the cyclic charge-discharge process.