One-step combustion synthesis of carbon-coated NiO/Ni composites for lithium and sodium storage

Using carbon dioxide and nickel nitrate as the carbon and nickel sources respectively, a carbon-coated NiO/Ni (NiO/Ni@C) composite was synthesized via a one-step solution combustion method. Ethanolamine was used as the CO₂ adsorption solution, with nickel nitrate dissolved in it to form the combustion precursor at a molecular level. The as-obtained NiO/Ni nanoparticles exhibited spherical morphology with an average size of 30 nm, and controlled carbon content ranging from 50 to 90 wt%. The NiO/Ni@C composites were investigated as anode material for lithium and sodium ion batteries, exhibiting high reversible specific capacity and excellent rate performance. The NiO/Ni@C-0.25 sample showed a reversible capacity of 125 mAh g⁻¹ with a specific current of 0.1 A g⁻¹ as sodium ion anode, and a capacity of 791 mAh g⁻¹ with a specific current of 0.1 A g⁻¹ after 150 cycles as lithium ion anode. Owing to the novel one-step combustion process and resulting superior electrochemical performance, the NiO/Ni@C composite is demonstrated as a prospective anode material for rechargeable lithium and sodium ion batteries.