Effects of deposition potential and anneal temperature on the hexagonal nanoporous nickel hydroxide films

In this study, improvement in the electrochemical performance of the nickel hydroxide film electrode has been pursued by (i) using nonionic surfactant Brij 56 as the structure-directing agent, (ii) varying the deposition potentials, and (iii) varying the anneal temperatures. Nanoporous nickel hydroxide films are successfully electrodeposited onto titanium substrates from the hexagonal lyotropic liquid crystal template of Brij 56. The films are physically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) to determine the effects of deposition potentials and anneal temperatures on the surface morphology. Electrochemical techniques such as cyclic voltammetry (CV) and chronopotentiometry are used to systematically study the effects of deposition potentials and anneal temperatures on the capacitance of the films. The specific capacitance as high as 578 F g(-1) is achieved for the H-I-e Ni(OH)(2) film deposited at -0.70 V versus SCE and heat-treated at 100 degrees C for 1.5 h, indicating its potential application as a low-cost, high-performance electrode material in electrochemical capacitors.