Effects of Cationic Surfactant in Sol-gel Synthesis of Nano Sized Magnesium Oxide

Abstract

In this study, sol-gel method was used to synthesize nano sized of magnesium oxide (MgO). Magnesium acetate tetrahydrate and tartaric acid have been dissolved in ethanol and formed a precursor before calcined at 600 ¡C for 6h to produce MgO nanoparticles. A cationic surfactant (cetyltrimethylammonium bromide, CTAB) had used in the sol-gel reaction to reduce agglomeration of the nanoparticles. Two samples (MgO and MgO-CTAB) were characterized using simultaneous thermogravimetric analyzer (STA), X-ray diffractometer (XRD), field emission scanning electron microscope (FESEM) and nitrogen adsorption-desorption measurement. Formation of the samples via a sol-gel route is discussed and confirmed using the STA results. The precursor formed was identified as magnesium tartrate and decomposed to MgO and MgO-CTAB after the calcinations, and gave a single phase of samples as shown by the XRD patterns. The used of CTAB in this sol-gel method gives the MgO nanoparticles with less agglomeration. This was proved by the FESEM micrographs, the MgO-CTAB has spherical shape and the agglomeration seems to be less than the MgO. It suggests that the cationic surfactant controls the morphology of the samples.