Controlled synthesis of Ni0.25Co0.75(OH)2 nanoplates and their electrochemical properties

Abstract

Hexagonal Ni_0.25Co_0.75(OH)₂ nanoplates with rough and smooth surfaces have been synthesized with various amounts of CTAB by a mild wet chemical approach. The diameters of these two nanoplates are estimated to be ~150 nm and their thicknesses are ~30 nm. The electrochemical properties of the hexagonal nanoplates have also been investigated by using a three-electrode system under alkaline conditions. The scobinate Ni_0.25Co_0.75(OH)₂ nanoplates show enhanced supercapacitor capacity compared with the smooth samples. For scobinate nanoplates, the specific capacitance is 306 F g⁻¹ at a current density of 0.5 A g⁻¹ and remains 90% as the current density increases 16 times. At a current density of 3 A g⁻¹, the specific capacitance still remains 98% after 7000 cycles.