Abstract

Cobalt hydroxide with an interlayer spacing of 7.53 Å and needle-like morphology has been synthesized with the aid of ultrasound radiation. Characterization by powder X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, FT-IR spectroscopy, as well as elemental analysis, indicates the formation of α-cobalt hydroxide. Thermal decomposition of the hydroxide at 300 °C under air or argon yields nanometer-sized oxide particles of Co₃O₄ (ca. 9 nm) and CoO (ca. 6 nm), respectively.