Low temperature synthesis of nanocrystalline magnesium aluminate spinel by a soft chemical method

A new simple soft chemical method – synthesizing nanocrystalline MgAl₂O₄ spinel powder with oxalic acid as organic template and nitric acid as an oxidizing agent – is described. The method was developed with the objective of obtaining phase pure nanocrystalline MgAl₂O₄ spinel powder with uniform particle size and morphology at a much lower temperature than that used by conventional methods. The synthesized powders were characterized by X-ray diffractometry (XRD), thermogravimetry (TGA), Fourier transform infrared spectroscopy (FTIR), surface area analysis (BET) and field emission scanning electron microscopy (FE-SEM). The average crystallite size of the single phase material was 30 nm. Through this method, porous MgAl₂O₄ powder with a high surface area of 162.2 m²g⁻¹ and 141 m²g⁻¹ was obtained at 600 °C and 700 °C, respectively.