Raspberry-like hollow Ni/NiO nanospheres anchored on graphitic carbon sheets as anode material for lithium-ion batteries

Raspberry-like hollow NiO nanospheres anchored on graphitic carbon sheets (GCS) are synthesized by anchoring Ni2+ to a polymeric matrix of citric acid and ethylene glycol in the presence of NaCl as morphology controller. In situ formed Ni(0) nanoparticles served as catalysts in the graphitization of the formed carbon sheets, which led to the enhanced conductivity of the carbon sheets. The Ni(0) particles are subsequently transformed into NiO nanoparticles. The NiO/GCS composite exhibits improved electrochemical performance with a reversible capacity of 1076.2 mA h g(-1) after 50 cycles at 0.1C within the voltage range of 0.01-3.0 V when compared to those of bare NiO (similar to 285.8 mA h g(-1)). In addition, the NiO/GCS composite can discharge large reversible capacities of approximately 1073.6 mA h g(-1) at 0.5C and 966.6 mA h g(-1) at 1 C after 300 cycles. (C) 2019 Elsevier B.V. All rights reserved.