Size-controllable Co₃O₄ nanograin-decorated Co(OH)₂ sheets synthesized with MOF templates for highperformance all-solid-state asymmetric supercapacitor electrodes

13^th International Conference on Electrochemistry

May 27-28, 2019 | Barcelona, Spain

Gyeongseop Lee

Seoul National University, South Korea

Posters & Accepted Abstracts: J Biosens Bioelectron

Abstract :

In this study, a novel hybrid structure of homogeneously distributed Co3O4 nanograins on a hexagonal Co(OH)2 plate (CNG/Co(OH)2) is synthesized using a one-pot hydrothermal reaction of zeolitic imidazolate framework-67 (ZIF-67). Particularly, because Co-containing ZIF-67 serves as a self-template during the hydrothermal conversion process, various-sized CNG/Co(OH)2 can be prepared using different sizes of ZIF-67 as the precursor material. The unique structural features of CNG/Co(OH)2 effectively boost the electrochemical activation of the active materials (i.e., Co3O4, Co(OH)2) by preventing aggregation. Among the various-sized CNG/Co(OH)2, large-sized CNG/Co(OH)2 (L_CNG/Co(OH)2) exhibits the highest capacitance (1284 F gâ??1 at 1 A gâ??1), indicating that the electrochemical performance is improved as the size of the hybrid architecture increases. Furthermore, multifarious all-solid-state asymmetric supercapacitors (ASCs) are successfully fabricated with various-sized CNG/Co(OH)2 as the positive electrode and mesoporous plasma-reduced graphene oxide (MPRGO) as the negative electrode. Owing to the synergistic contributions from the two electrodes, the L_CNG/Co(OH)2-based ASC delivers a maximum energy density of 41.2 Wh kgâ??1 at 2.8 kW kgâ??1, and holds 31.5 Wh kgâ??1, even at the highest power density of 45 kW kgâ??1, demonstrating great potential for next-generation energy storage devices.

Biography :

Gyeongseop Lee received his BSc in Chemical and Biological Engineering from the Sogang University in 2014. He is currently pursuing a PhD degree in Chemical and Biological Engineering at the Seoul National University under the supervision of Prof. Jyongsik Jang. His research mainly focuses on zeolitic imidazolate framework-derived materials and their composites for supercapacitor applications.