Hydrothermal synthesis and characterization of single crystalline Cu-doped α-FeOOH nanowires

Cu-doped α-FeOOH nanowires with diameters of 30–40 nm and lengths up to 1 μm were synthesized by a convenient hydrothermal method under mild conditions. X-ray powder diffraction (XRD) and high-resolution TEM (HRTEM) studies indicated that nanowires were single-crystalline with an oriented growth along the [1 3 0] direction. The effects of Cu-dopant content on the morphologies and crystalline phases characterized by field emission scanning electron microscopy (FE-SEM), Mössbauer and Fourier transform infrared (FT-IR) spectroscopies were also investigated. Obtained results indicated that α-(Fe,Cu)OOH nanowires were formed up to x = 2.5, whereas α-(Fe,Cu)2O3 nanocubes alone were obtained at x = 10, where m(Fe:Cu) = 100:x.