Dandelion-like nickel/cobalt metal-organic framework based electrode materials for high performance supercapacitors

Shuwen Gao; Yanwei Sui; Fuxiang Wei; Jiqiu Qi; Qingkun Meng; Yaojian Ren; Yezeng He

doi:10.1016/j.jcis.2018.07.044

Dandelion-like nickel/cobalt metal-organic framework based electrode materials for high performance supercapacitors

J Colloid Interface Sci. 2018 Dec 1:531:83-90. doi: 10.1016/j.jcis.2018.07.044. Epub 2018 Jul 17.

Authors

Shuwen Gao¹, Yanwei Sui¹, Fuxiang Wei¹, Jiqiu Qi¹, Qingkun Meng¹, Yaojian Ren¹, Yezeng He²

Affiliations

¹ School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 221116, People's Republic of China.
² School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 221116, People's Republic of China. Electronic address: hyz0217@hotmail.com.

PMID: 30025331
DOI: 10.1016/j.jcis.2018.07.044

Abstract

Metal-organic frameworks (MOFs), serving as a promising electrode material in the supercapacitors, have attracted tremendous interests in recent years. Here, through modifying the molar ratio of the Ni²⁺ and Co²⁺, we have successfully fabricated Ni-MOF and Ni/Co-MOF by a facile hydrothermal method. The Ni/Co-MOF with a dandelion-like hollow structure shows an excellent specific capacitance of 758 F g^-1 at 1 A g^-1 in the three-electrode system. Comparing with Ni-MOF, the obtained Ni/Co-MOF has a better rate capacitance (89% retention at 10 A g^-1) and cycling life (75% retention after 5000 circulations). Besides, the assembled asymmetric supercapacitor based on Ni/Co-MOF and active carbon exhibits a high specific energy density of 20.9 W h kg^-1 at the power density of 800 W kg^-1. All these results demonstrate that the mixed-metal strategy is an effective way to optimize the morphology and improve the electrochemical property of the MOFs.

Keywords: Ni-MOF; Ni/Co-MOF; Supercapacitors.