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

• Published in: Journal of colloid and interface science Vol. 531; pp. 83 - 90
• Main Authors: Gao, Shuwen, Sui, Yanwei, Wei, Fuxiang, Qi, Jiqiu, Meng, Qingkun, Ren, Yaojian, He, Yezeng
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.12.2018
• Subjects: capacitance; carbon; cobalt; coordination polymers; electrochemistry; electrodes; hot water treatment; Ni-MOF; Ni/Co-MOF; nickel; specific energy; Supercapacitors; Supercapacitors; Ni-MOF; Ni/Co-MOF
• ISSN: 0021-9797; 1095-7103; 1095-7103
• DOI: 10.1016/j.jcis.2018.07.044

[Display omitted] 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.