Ni(OH)2 nanodot-decorated Co-Co LDH/C hollow nanocages for a high performance supercapacitor.

A novel Co-Co LDH/C/Ni(OH)2 nanostructure was constructed by loading Ni(OH)2 nanodots on hollow Co-Co LDH/C nanocages derived from MOFs. The Co-Co LDH/C/Ni(OH)2 nanostructure revealed a high specific capacitance of up to 1426 F g-1 at 1 A g-1 and an outstanding rate capability with 90.2% retention at 10 A g-1 owing to the cooperative effect of the Ni(OH)2 nanodots and hollow Co-Co LDH/C nanocages. The electrochemical kinetic analysis showed that the Co-Co LDH/C/Ni(OH)2 electrode was dominated by surface capacitance control, demonstrating the origins of performance improvement. This work may provide an effective strategy by combining nanodots with hollow porous structures for low-cost and efficient energy storage materials.