Construction of flower-like spherical CoFe2O4@Co3O4 based on zeolitic imidazolate framework as high-performance electrode materials for supercapacitors

Ferrite, a class of transition metal oxides, has emerged as a promising material for electrochemical energy storage due to its cost-effectiveness and high theoretical capacity. However, the tendency of ferrite to agglomerate hinders its practical application. Here, we report a facile method to fabricate CoFe 2 O 4 @Co 3 O 4 flower-like sphere and form a unique core-shell structure. In this composite, flake Co 3 O 4 pile up to form shell which cladding the CoFe 2 O 4 core. Crumpled shell provide ultra-high specific surface area (128.54 m 2 /g) to expose more electrochemical active sites, benefiting effective electrons transfer. As a result, the optimized flower-like spherical structure electrode exhibited an exceptionally high capacity of 2834 F g −1 at a current density of 1 A g −1 . Additionally, the electrode demonstrated outstanding rate capability, retaining 78 % of its capacity at a current density of 10 A g −1 .