초록 |
In this study, Co3O4 nanograin-decorated Co(OH)2 sheet (CNG/Co(OH)2) is synthesized by the hydrothermal reaction of zeolitic imidazolate framework-67 (ZIF-67). Particularly, because ZIF-67 serves as a self-template during the hydrothermally conversion process, various-sized CNG/Co(OH)2 could be prepared by using different size of ZIF-67. Among them, large-sized one (L_CNG/Co(OH)2) exhibits the highest capacitance (1284 F g–1 at 1 A g–1), indicating that the electrochemical performance is improved as the size of hybrid architecture increases. Furthermore, the multifarious asymmetric supercapacitors (ASCs) are fabricated with various-sized CNG/Co(OH)2 as the positive electrode and mesoporous plasma-reduced graphene oxide as the negative electrode. Notably, the L_CNG/Co(OH)2 based ASC delivers a maximum energy density of 41.2 Wh kg–1 at 2.8 kW kg–1. |