The effect of magnesium salt on the morphological development of MgO powders synthesized by the evaporative decomposition of solutions (EDS) technique is presented. Thermal analysis at 10 and 100 °C min-1 was used to determine the effect of increased heating rate on the decomposition temperatures of Mg(C2H3O2)2·4 H2O, MgCl2·6 H2O, and Mg(NO32·6 H2O. Full decomposition to MgO powder was only achieved during EDS with magnesium acetate and magnesium nitrate. The decomposition of the chloride precursor during EDS was incomplete as a result of kinetic limitations imposed by the high heating rate (∼ 300 °C s-1) associated with the EDS process. Generally, the particle morphology consists of large aggregates when produced from the chloride and nitrate salts. However, fine, dispersed, sub-micrometer particles are formed from magnesium acetate under oxidizing conditions. These differences are demonstrated to be a direct result of the decomposition path of the magnesium salt.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Physical and Theoretical Chemistry