Rational synthesis of bimetallic CoFe-MOF-74 grown on Ni foam converted into bamboo-shoot-like α-Co(OH)2/CoFe2O4 nanorods for high-performance supercapacitors

Owing to the high specific surface area, rich active sites, well-controlled morphology and structural stability with tunable compositional components, the rational combination of hybrid nanostructured materials from metal-organic frameworks templates has become highly attractive and still of great challenge for supercapacitors. In this work, three bimetallic metal–organic frameworks Co1-xFex-MOF-74/NF (x = 0.25, 0.5 and 0.75) nanoarrays with different proportional Co/Fe ratios on nickel foam have been successfully designed and fabricated via in-situ interfacial growth method, which were further controllable converted to α-Co(OH)2/CoFe2O4 nanoarrays with different proportional Co/Fe ratios CF-x/NF (x = 0.25, 0.5 and 0.75) without structure collapse through alkaline etching process. Among them, the transformation of the bamboo-shoot-like CF-0.75/NF electrode displays excellent electrochemical properties with high area capacitance (3941.14 mF/cm2 at 2 mA/cm2), good rate capability, low resistances and remarkable cycling stability. The CF-0.75//AC ASC device delivers a high energy density of 0.16 mWh/cm2 at a power density of 0.756.1 mW/cm2. And this CF-0.75//AC ASC device exhibits a good cycling stability and practical application in energy storage field. This strategy could be extend to form other unique bimetallic hybrids nanoarrays architectures with enhanced electrochemical activity for high-performance energy storage devices.