关键词: 尿素水热法, 片层花状MgCo₂O₄, 比电容, 循环性能

Abstract: The capacitive performance of spinel-type nanomaterials mainly depends on their particle size，specific surface area，microscopic morphology and structure. In order to obtain better electrode materials for supercapacitors，we prepared 3D MgCo₂O₄ with lamellar flower-like structures composed of nanosheets， using the urea-based hydrothermal method at a lower temperature（120 ℃）。The size of the nanosheet varied with a smaller size of approximately 7. 34 μm and a larger size of approximately 15. 38 μm. The thickness of the nanosheets was uniform，approximately 63. 9 nm. The sample was characterized by X-ray diffraction，scanning electron microscopy and electrochemical workstation. The result indicated that the specific capacity could reach 315. 6 F/g at the current density of 1 A/g. Additionally，after 4 000 cycles of MgCo₂O₄ material with lamellar flower-like structure，the loss was only 26. 5%，showing good cycling stability.

Key words: urea-based hydrothermal method, lamellar flower-like MgCo₂O₄, specific capacitance, cycling performance