Electrochemical fabrication and characterization of lepidocrocite (γ-FeOOH) nanowire arrays

We report on the fabrication of γ-phase iron oxyhydroxide (γ-FeOOH, lepidocrocite) nanowire (nw) arrays within the alumina pores by electrodeposition. An aqueous solution, friendly to alumina matrix, was generated and applied in this study for uniform deposition of γ-FeOOH nw arrays directly through the alumina barrier layer using an alternating current (ac) mode. As-deposited nanowired products were characterized using 57Fe Mössbauer spectroscopy (MS), atomic absorption spectrophotometry analysis, field-emission scanning electron microscopy, UV–vis transmission spectroscopy, transmission electron microscopy and X-ray diffraction. The formation of pure lepidocrocite nw arrays in the alumina pores with the average Øpore of 45 and 150 nm was verified by transmission MS at cryogenic temperatures.