Net-structured Co3O4/C nanosheet array with enhanced electrochemical performance toward lithium storage

• Published in: Materials research bulletin Vol. 51; pp. 112 - 118
• Main Authors: Yu, Y.X., Liu, X.Y., Xia, X.H., Xiong, Q.Q., Wang, X.L., Gu, C.D., Tu, J.P.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.03.2014
• Subjects: A. Surfaces; B. Chemical synthesis; C. Electrochemical measurements; D. Electrochemical properties; D. Energy storage; B. Chemical synthesis; D. Electrochemical properties; C. Electrochemical measurements; A. Surfaces; D. Energy storage
• ISSN: 0025-5408; 1873-4227
• DOI: 10.1016/j.materresbull.2013.11.043

•Co3O4/C nanosheet array on nickel foam was synthesized by hydrothermal method, followed by magnetron sputtering of a carbon layer.•The Co3O4/C nanosheet array electrode delivers an initial discharge capacity of 1340.4mAhg−1 at 0.1C.•After 100 cycles, the capacity retention of the Co3O4/C is 88.8% of its initial discharge capacity.•The enhanced electrochemical performances are attributed to the porous nanosheet array and the thin carbon layer coated on Co3O4 nanosheets. Freestanding Co3O4/C nanosheet array growing directly on nickel foam substrate was synthesized using a hydrothermal approach, followed by a direct current magnetron sputtering of a thin carbon layer. The Co3O4 nanosheets with thicknesses of 10–20nm are interconnected with each other, forming a highly open net-structure. The Co3O4/C nanosheet array electrode delivers an initial discharge capacity of 1340.4mAhg−1 at 0.1C, and maintains a high specific capacity of 912.1mAhg−1 at room temperature and can still remain 88.8% of its initial discharge capacity at 55°C at 1C after 100 cycles. The enhanced electrochemical performances are attributed to the porous nanosheet array and the thin carbon layer coated on Co3O4 nanosheets, which cannot only facilitate Li+ and electron transportation in the electrode, but also improve its structure stability during cycling.