New insight on nanostructure assembling of high-performance electrode materials: synthesis of surface-modified hexagonal β-Ni(OH)2 nanosheets as an example

Hexagonal β-Ni(OH) 2 nanosheets with thickness of ∼12 nm were synthesized by a hydrothermal method at 150 °C using nickel chloride as nickel source and morpholine as alkaline. Electrodes for application in pseudocapacitor were assembled through a traditional technique: pressing a mixture of β-Ni(OH) 2 nanosheets and acetylene black onto nickel foam. Due to the hexagonal shape of rigid β-Ni(OH) 2 nanosheet and the mediation of surface-modified glycerol during electrochemical charge–discharge cycles, a nanostructure of electrode material with facile interior pathway for the transfer of electrolyte was formed. As a result, the as-formed electrodes presented high specific capacitance of 1,917 F g −1 at current density of 1.6 A g −1 in 3 mol L −1 KOH solution. At high charge and discharge current density of 31.3 A g −1 , the electrodes still remained a high specific capacitance of 1,289 F g −1 . The interesting results obtained from this investigation may provide a new insight for the synthesis of electrode materials with high electrochemical performance.