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

Abstract

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.