Room-temperature synthesis of Mg(OH)2 nanorods and nanowires in Mg-H2O-NaC1 reaction system

A novel method based on the reaction between Mg foil and water in the presence of NaCl has been employed to synthesise one-dimensional (1D) Mg(OH)₂ nanostructures. It is found that the presence of NaCl not only increases the reaction rate but also results in the formation of 1D Mg(OH)₂ nanostructures with their morphologies being related to the NaCl concentration. Nanorods with 100-400 nm in width and more than 1 μm in length are observed when the NaCl concentration is low, whereas nanowires with 20-120 nm in diameter and several micrometres in length and their self-assembled nest-like structures are formed in the case of high NaCl concentration. The authors´ results have also shown that both nanorods and nanowires grow along the [110] direction. Based on experimental observations, a possible mechanism is proposed for the growth of 1D Mg(OH)₂ nanostructures and their self-assembled structures.