Porous nanotubes derived from a metal-organic framework as high-performance supercapacitor electrodes

In this work, porous Co3O4 nanotubes were prepared by calcining nanoscale Co-MOF-74 crystals at an optimized temperature. The shell of the Co3O4 nanotubes consisted of small interconnected nanoparticles. Supercapacitors were successfully constructed using the resulting porous Co3O4 nanotubes as electrode materials. Electrochemical data demonstrated that the Co3O4 nanotubes exhibited good capacitive behavior with a specific capacitance of 647 F g−1 at a current density of 1 A g−1. Apart from high capacitance, the Co3O4 nanotubes also demonstrated excellent cycling stability with no obvious decrease after 1500 cycles at 2 A g−1, which indicated that it can be promising electroactive materials for supercapacitors. The remarkable performance of the nanotubes could be attributed to their special morphology and appropriate pore-size distribution.