Electrophoretic deposition of nanographitic flakes/Co3O4 nanocomposite layers synthesized by solvothermal process for improved lithium-ion-battery anode

Different morphologies of Co3O4 nanopoarticles formed on nanographitic flakes are synthesized based on the decomposition of cobalt acetate precursor in ethylene glycol at 180 ​°C for 18 ​h by a solvothermal process followed with a heat treatment at the different temperatures of 350, 450, and 550 ​°C. Then, an electrophoretic deposition process is used to form the composite layers on the stainless steel plates. Among those temperatures, the layer prepared at 450 ​°C shows superior morphology and less aggregated nanoparticles, which is consistent with the electrochemical battery experiments. The electrode fabricated at 450 ​°C shows a charge capacity of 428 ​mA/g after 50 cycles at 1 A/g with a total retention of 90% which is higher than the charge capacities of the other electrodes heated at 350 and 550 ​°C. The cycling and rate performance results for the fabricated electrode heated at 450 ​°C manifest the superior distribution of the Co3O4 nanoparticles on the nanographitic flakes.