Microstructure-controlled synthesis of nickel oxide nanowires by thermal oxidation of nickel nanowires

A simple, low-cost and controllable transformation of Ni nanowires into NiO nanowires is managed through a thermal oxidation process. Ni nanowires, with an average diameter of 40 nm, were prepared as sacrificial templates and thermally oxidized at an elevated temperature to synthesize NiO nanowires. By adjusting the thermal oxidation temperature, the microstructure of the NiO nanowires could be tuned from having a highly porous structure to a dense one with connected large crystallites. The synthesized NiO nanowires have a wide range of applications in supercapacitors, lithium ion batteries, catalysts and ReRAM because of their dimensionalities and controllable microstructures.