Nanoscale Magnesium Hydroxide and Magnesium Oxide Powders: Control over Size, Shape, and Structure via Hydrothermal Synthesis

Mg(OH)2 nanocrystallines with rod-, tube-, needle-, or lamella-like morphologies have been synthesized by a hydrothermal reaction using different magnesium precursors and solvents as the reactants. The products appeared to have narrow size distributions with a monodisperse nature. Subsequent thermal decomposition at 450 °C gave nanosized MgO, which preserved well the morphological features of the Mg(OH)2 samples. The specific surface areas of the MgO samples were determined by the BET technique, which gave a feature of high surface area generally larger than 100 m2/g. The channels formed in the thermal dehydroxylation process may account for this feature of the MgO nanocrystallines.