In Site Growth of Crosslinked Nickel–Cobalt Hydroxides@Carbon Nanotubes Composite for a High‐Performance Hybrid Supercapacitor

Abstract Metal–organic frameworks materials have shown great potential in energy storage and conversion research, but their poor electrical conductivity and inferior chemical stability limit their applications. Herein, an in situ‐grown crosslinked nickel–cobalt hydroxides@carbon nanotubes composite with a nanosheet‐covered hollow structure is rationally designed and synthesized successfully from ZIF‐67@carbon nanotubes. Different from other studies, the carbon nanotubes in this composite penetrate the hollow structure, and the active nanosheets also grow on the parts protruding from the hollow boxes via this in situ synthetic route. Compare with pure nickel–cobalt hydroxides, the composite exhibits enhanced electroactivity in terms of the specific capacity and cycling performance. In particular, it delivers a high specific capacity of 916.8 C g −1 at 1 A g −1 and ≈79.0% of its initial value preserves after 4000 cycles. This facile synthetic approach enables the preparation of crosslinked metal–organic framework materials with the potential to meet the demands of energy storage and conversion devices as well as supercapacitors.