Preparation and bactericidal property of MgO nanoparticles on gamma-Al2O3.

After being impregnated in the solution containing Mg(NO3)2 x 6H2O, gamma-Al2O3 was dried and calcined at 500 degrees C which results in the production of a bactericide, highly dispersed MgO loaded on the surface of gamma-Al2O3. The threshold value of the monolayer dispersion of MgO on gamma-Al2O3 is 14.97%, and MgO crystal formed when the load amount beyond this value. The samples with different load amount were characterized by X-ray Diffraction (XRD), Low-temperature N2 adsorption-desorption, Inductively Coupled Plasma (ICP) and High Resolution Scan Electronic Microscope (SEM). The results showed that these MgO microcrystals are highly dispersed and have regular size in the range of 4 to 10.8 nm. The specific surface, pore volume and pore size of the sample decreases with the increase of load amount. It is demonstrated that gamma-Al2O3 with highly dispersed MgO on the surface is efficient bactericide, and the one with 20% load amount of MgO can kill more than 99% bacteria and spore cells.