Ultralong cadmium hydroxide nanowires: Synthesis, characterization, and transformation into CdO nanostrands

Ultralong Cd(OH)₂ nanowires were fabricated by a hydrothermal method from Cd(CH₃COO)₂·2H₂0 (0.01 mol/L) and C₆H₁₂N₄ (0.015 mol/L) aqueous solution at 95°C for 16 h without using any templates and were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and high-resolution transmission electron microscopy (HRTEM). The length of the nanowires reached several micrometers, giving an aspect ratio of a few thousands. The formation mechanism of the nanowires is attributed to the oriented attachment of small particles. The growth method for the ID nanostructure presented here offers an excellent tool for the design of other advanced materials with anisotropic properties. The Cd(OH)₂ nanowires efficiently captured negatively charged dye, and the adsorbed dye molecules can be released after the addition of EDTA. The Cd(OH)₂ nanowires as template compounds were further transformed into CdO semiconductor nanomaterials with similar morphology by calcination under 350°C in air for 3 h.