Morphology–controlled synthesis of the porous Co3O4 with rugby–shaped and spherical structures and theirs electrochemical properties as negative materials for Li–ion batteries

Morphology‒controlled porous Co3O4 electrode materials with rugby‒shaped and spherical structures are synthesized through a facile solvothermal method followed by annealing treatment, and the regulation of the morphologies is accomplished by simply adjusting the concentration of the reactants. According to the N2 adsorption–desorption isotherm curves, the samples have a relatively rich mesoporous structure, and the Barrett–Joyner–Halenda (BJH) pore size distributions are found at 2.5 and 32.8 nm for the Co3O4 sample with rugby‒shaped structure (denoted as R–Co3O4), and 2.2 nm for the spherical Co3O4 sample (denoted as S–Co3O4). Simultaneously, the Brunauer–Emmett–Teller (BET) surface areas of the R–Co3O4 and S–Co3O4 samples are 31.3 and 26.7 m2 g−1, respectively. Electrochemical properties of the samples as anode materials for Li‒ion batteries show that the R–Co3O4 electrode material has higher specific capacity, better rate performance and superior cycle stability than the S–Co3O4 for the higher specific surface area, richer pore size distribution, nanosized particles, lower charge transfer resistance and better reaction reversibility. [Display omitted] •Co3O4 samples with different micro‒nano structures are prepared in this work.•No hard or soft template is adding during the synthesis process.•The Co3O4 samples exhibit excellent rate capability and cycling stability.