Microstructure of porous network CoFeO@CoO/CNT based on zeolitic imidazolate framework as electrode materials for supercapacitors application.

Transition metal oxides (TMOs), especially spinel-type iron oxides, are widely used as electrode materials for supercapacitors due to their high specific capacitance. However, as a kind of pseudocapacitive electrode material, transition metal oxide undergoes volume changes during the charge-discharge process, leading to a decrease in its cycling stability. Carbon nanotubes (CNTs), as a common carbon-based material, exhibit excellent cycling stability. In this study, we have successfully synthetized CoFeO@CoO/CNT by utilizing zeolitic imidazolate framework (ZIF) as a template. The resultant material exhibits a porous network architecture and the synthesized material was subsequently utilized as an electrode in supercapacitor applications, exhibiting a remarkable specific capacitance of 641 C g at 1 A g. The stability of the electrode were evidenced by its ability to retain 62.3% of its initial capacitance after 5000 cycles at the high current density of 10 A g, indicating its potential for long-term energy storage applications.