Cu-doped alpha-FeOOH nanowires with diameters of 30-40 nm and lengths up to 1 mu m 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), Mossbauer and Fourier transform infrared (FT-IR) spectroscopies were also investigated. Obtained results indicated that alpha-(Fe, Cu) OOH nanowires were formed up to x = 2.5, whereas alpha-(Fe,Cu)(2)O-3 nanocubes alone were obtained at x = 10, where m(Fe:Cu) = 100:x. (C) 2012 Elsevier B. V. All rights reserved.