Homogeneous nickel metal-organic framework microspheres on reduced graphene oxide as novel electrode material for supercapacitors with outstanding performance

• Published in: Journal of colloid and interface science 2020-03, Vol.561, p.265-274
• Main Authors: Zhong, Yuxue, Cao, Xueying, Ying, Liu, Cui, Liang, Barrow, Colin, Yang, Wenrong, Liu, Jingquan
• Format: Article
• Language: English
• Subjects: Hydrothermal and calcining process; Ni-MOF microspheres; rGO; Supercapacitor
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2019.10.023

[Display omitted] Herein, we designed and prepared nickel metal-organic framework microspheres anchored directly on reduced graphene oxide (Ni-MOF/rGO) by a facile hydrothermal and successive calcining process. The electrode for Ni-MOF/rGO composite annealed at an optimized temperature of 300 °C (Ni-MOF/rGO-300) shows desired conductivity, good cycling stability and high ion-accessible surface area, leading to an ultrahigh specific capacitance of 954 F g−1 at a current density of 1 A g−1 and a remarkable rate capability of 80.25% at 5 A g−1. Meanwhile, the assembled Ni-MOF/rGO-300//activated carbon asymmetric supercapacitor (ASC) shows a favorable energy density up to 17.13 Wh kg−1 at a power density of 750 W kg−1 in the potential window of 0–1.5 V. Moreover, the capacitance retention can still maintain 81.63% after 4000 cycles at a high current density of 5 A g−1. The excellent electrochemical properties can be credited to the synergistic effects between the unique structures of Ni-MOF and rGO, which makes the Ni-MOF/rGO composite a potential electrode material for high performance supercapacitors.