Synergistic effect of bimetallic NiCo-MOF on foamed nickel for application in high-performance supercapacitors

In this study, a series of bimetallic NiCo-MOFs with nanorod-like structures were successfully prepared on a foamed nickel skeleton. By adjusting the elemental ratio of nickel-cobalt, the synergistic effect between them was enhanced, thus improving the performance of the electrode material. Interestingly, it was found that with an increase in the Co2+ content the diameter of the nanorods becomes slender, which is conducive to the performance of supercapacitors. The performance is best when the nickel-cobalt ratio is 1 : 4, and the specific capacitance reaches 1894.3 F g-1 when the current density is 1 A g-1. At a current density of 10 A g-1, the capacitance retention reaches 80.2% after 1000 GCD cycles. The button-type supercapacitor NiCo-MOF-2//AC assembled from it also has excellent electrochemical performance. When the current density was 5 A g-1, the measured specific capacitance of the button supercapacitor was as high as 300.7 F g-1. The stability of the device was tested at a current density of 10 A g-1 and the capacitance retention was 87.9% after passing 5000 charge and discharge cycles. Therefore, the bimetallic NiCo-MOF prepared in this study has great application potential in supercapacitors. In this study, a series of bimetallic NiCo-MOFs with nanorod-like structures were successfully prepared on a foamed nickel skeleton.