Synthesis of porous, high surface area MgO microspheres

Abstract

Porous MgO microspheres with nanocrystallites have been prepared by a wet precipitation process using ammonium hydrogen carbonate and ammonium hydroxide as precipitants. The as-precipitated powders are composed of crystalline Mg 5(OH) 2(CO 3) 4.4H 2O microspheres with porous and hollow microstructure and are decomposed and transformed to nanocrystalline cubic MgO after being calcined at 500 °C. The average crystallite size of MgO microspheres increases from 10 nm to 31.6 nm with increasing temperature from 500 °C to 1100 °C. The surface area of the MgO powder decreases from 90.7 m 2/g to 31.5 m 2/g with increasing temperature from 500 °C to 1100 °C.