An assembled-nanosheets discus-like Ni(OH)2 hierarchical structure as a high performance electrode material for supercapacitors

An assembled-nanosheets discus-like Ni(OH)2 hierarchical structure is synthesized through a facile solvothermal method without any surfactant used in the synthesis. The morphology and microstructure of the Ni(OH)2 products can be tuned using the solvothermal temperature. The as-prepared Ni(OH)2 samples are investigated as electrode materials for supercapacitors. It is found that the assembled-nanosheets Ni(OH)2 hierarchical structure exhibits excellent capacitive performance with a specific capacitance as high as 1830.3 F g−1 at a current density of 1.0 A g−1, great electrochemical stability with a capacitance retention of 98.9% after 1000 cycles at a constant current density of 10 A g−1, and a high energy density of 146.4 W h kg−1. The remarkable capacitive performance can be attributed to the unique hierarchical structure of the Ni(OH)2 product, which can facilitate the penetration and migration of electrolyte ions, shorten the diffusion distance of charges and increase the utilization of active materials. The excellent capacitive performance makes the Ni(OH)2 hierarchical architecture a promising electrode material for electrochemical energy storage applications.