Graphene Oxide-Wrapped Porous Hollow Co₃O₄ Microspheres with Enhanced Lithium Storage Performance

Abstract

Porous\nhollow Co₃O₄ microspheres wrapped with graphene oxide were synthesized\nby a step solvothermal method and subsequent heat treatment. Benefiting\nfrom the design of special porous hollow microspheres, the effective\nspecific surface area was greatly increased, the sufficient contact\nbetween the porous hollow Co₃O₄ microspheres\nand electrolyte was achieved, and then a charge specific capacity\nof 888.59 mA h g^–1 was gained. Meanwhile, partial\nstress from the charging/discharging process was greatly relieved\ndue to the abundant pores and hollow structure, excellent cycling\nstability was realized, and the charge specific capacity of the 1000th\ncycle was 465.75 mA h g^–1 at 5 C (1 C = 890 mA g^–1). In addition, the conductivity of Co₃O₄ microspheres was effectively improved due to the tight\npackage of graphene oxide to Co₃O₄ microspheres,\nand superior rate performance was attained (280.99 mA h g^–1 at 10 C).