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Microwave-Assisted Synthesis of NiCo₂O₄ Double-Shelled Hollow Spheres for High-Performance Sodium Ion Batteries.

ABSTRACT: The ternary transitional metal oxide NiCo₂O₄ is a promising anode material for sodium ion batteries due to its high theoretical capacity and superior electrical conductivity. However, its sodium storage capability is severely limited by the sluggish sodiation/desodiation reaction kinetics. Herein, NiCo₂O₄ double-shelled hollow spheres were synthesized via a microwave-assisted, fast solvothermal synthetic procedure in a mixture of isopropanol and glycerol, followed by annealing. Isopropanol played a vital role in the precipitation of nickel and cobalt, and the shrinkage of the glycerol quasi-emulsion under heat treatment was responsible for the formation of the double-shelled nanostructure. The as-synthesized product was tested as an anode material in a sodium ion battery, was found to exhibit a high reversible specific capacity of 511 mAh g^-1 at 100 mA g^-1, and deliver high capacity retention after 100 cycles.

SUBMITTER: Zhang X

PROVIDER: S-EPMC6199058 | biostudies-literature |

REPOSITORIES: biostudies-literature

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