Synergistic effect of bimetal (Zn/Ni)–organic framework/reduced graphene oxide for high-performance supercapacitor

• Published in: Applied surface science 2023-04, Vol.615, p.156435, Article 156435
• Main Authors: Jin, Jiuzeng, Wang, NaiYi, Wang, Yi, Wang, Yuhong, Sun, Ting
• Format: Article
• Language: English
• Subjects: MOF; rGO; Supercapacitor; Synergistic effect
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2023.156435

[Display omitted] •In the Zn/Ni-MOF/rGO composite, the distribution structure of Zn/ Ni-MOF can be controlled by changing the dosage of GO.•There is a synergistic effect which prevents each other from stacking between Zn/Ni-MOF and rGO. Meanwhile, rGO as conductive substrate enhances the conductivity of the compound.•The synthesized GMOF-25 has a high specific capacitance of 1644F/g. After 3000 cycles of charge–discharge, the capacitance retention rate is still 85.1%.•GMOF-25 has a flower-bud structure with a considerable specific surface area. Supercapacitors with the advantages of large capacitance, long cycle life and high energy density are prominent for innovation in energy storage components. Herein, Zn/Ni-MOF/rGO composites are successfully synthesized through a one-step solvothermal method. The MOF/rGO compounds exhibit mutually beneficial synergies in structure: rGO sheets prevent MOF microspheres from serious agglomeration, while MOF microspheres could be spacers for inhibiting the overlapping of rGO. When the mass of GO was 25 % of the mass of the metal salt, Zn/Ni-MOF microspheres are well-dispersed among cross-linked rGO sheets (GMOF-25). The GMOF-25 delivers a splendid specific capacitance of 1644 F/g at a current density of 1 A/g and acceptable stability (85.1 % of the capacitance retention rate after 3000 cycles). In addition, the GMOF-25//activated carbon asymmetric supercapacitor displays a high energy density of 47.4 Wh/kg at a power density of 825 W/kg. The synergistic effect has been proved to play a vital role in promoting the electrochemical performance of supercapacitors via XRD, Raman and FTIR. This work provides a research approach for the design and manufacture of high-performance supercapacitors.