Two-dimensional porous NiCo₂O₄ nanostructures for use as advanced high-performance anode material in lithium-ion batteries

Two-dimensional (2D) porous NiCo₂O₄ nanostructures (NCO NSs) were investigated for use as an anode material in lithium-ion batteries (LIBs). The 2D porous NCO NSs were synthesized using a solvothermal technique, followed by annealing at different temperatures of 300, 400, and 500 °C (referred to as NCO-300, NCO-400, and NCO-500, respectively). High-resolution scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy analyses were used to examine the synthesized NCO NSs. The initial lithiation/de-lithiation capacities of the NCO-300, NCO-400, and NCO-500 electrodes were 1068.05 mA h g⁻¹/816.55 mA h g⁻¹, 1061.08 mA h g⁻¹/805.78 mA h g⁻¹, and 904.73 mA h g⁻¹/701.95 mA h g⁻¹, respectively at 100 mA g⁻¹. The NCO-400 electrode displayed relatively excellent rate performance and outstanding reversibility compared with the other two electrodes because of its ultrafine thickness and highly porous structure. According to our electrochemical results, the 2D porous NCO-400 electrode appears to be very promising for use as an advanced anode in high-performance LIBs.