A flower-like Co/Ni bimetallic metal-organic framework based electrode material with superior performance in supercapacitors

In this paper, a Co/Ni bimetallic metal-organic framework (ZIF-67 @Ni-salicylate) is successfully synthe-sized through a two-step method. By increasing the reaction time to 48 h, the effect of the hydrothermal treatment on structure changes and electrochemical properties of ZIF-67 @Ni-salicylate is demonstrated. Electrochemical measurements show that the ZIF-67 @Ni-salicylate hydrothermal-treated with 48 h pos-sesses a high specific capacitance of 1493 F g-1 at 1 A g-1 and simultaneously excellent cycle stability. Impressively, the capacitance retention rate can reach 86.8% even under a high current density of 40 A g-1, which is much better than that in previous reports. Furthermore, an asymmetric supercapacitor (ASC) is assembled and two ASCs connected in series can light up a red LED for more than 30 min as demonstrated by the current-time curve. Our work will be useful for the preparation of high-performance supercapacitor electrode materials.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

In this study, a Co/Ni bimetallic metal-organic framework material was successfully synthesized through a two-step method. The influence of hydrothermal treatment on its structure and electrochemical properties was investigated by increasing the reaction time to 48 hours. The results showed that the material treated with 48 hours of hydrothermal treatment exhibited high specific capacitance and excellent cycle stability. Additionally, an asymmetric supercapacitor was assembled and demonstrated stable and efficient performance under high current density.