The sucrose-assisted NiCo2O4@C composites with enhanced lithium-storage properties

Abstract

In this paper, porous NiCo2O4@amorphous carbon (NCO@C) composites have been designed and fabricated via a sucrose-assisted hydrothermal method where sucrose act as carbon sources and chelating agent, followed by annealing in air atmosphere. The synthesized NCO@C composites exhibited porous, polycrystalline, and carbon-coated nature. When it was used as anode material for lithium-ion batteries, the porous NCO@C composite electrode delivered a high discharge specific capacity of 1224.8 mAh g−1 with 133.6% of the second reversible capacity over 190 cycles at a current density of 500 mA g−1. Even at a current density as high as 4000 mA g−1, a reversible capacity of 675.4 mAh g−1 was still obtained. The enhanced Li-storage performance should be attributed to the porous and firm nanostructure coated with a thin amorphous carbon layer (∼2 nm), as well as synergistic effects of NCO@C composites.