High surface area homogeneous nanocrystalline bimetallic oxides obtained by hydrolysis of bimetallic μ-oxo alkoxides

Homogeneously dispersed bimetallic oxides in nanocrystalline or amorphous forms, of the type MAl2O4 (where M=Mg, Ca, Mn, Co, Fe, and Zn) were prepared from bimetallic oxo-bridged alkoxides [(RO)(2)Al-O-M-OAl (OR)(2)], where the Al-O-M-O-Al bonds were not hydrolytically cleaved. This approach yields hydroxides [(HO)(2)Al-O-M-O-Al(OH)(2)] which, upon thermal dehydration, yield oxides [OAl-O-M-O-AlO], such that M is homogeneously dispersed with an empirical formula of MAl2O4. These materials were obtained in high surface area forms and were characterized by X-ray diffraction, electron microscopy, surface area analyses, and solid-state Al-27 NMR. Comparative studies of the hydrolysis of alkoxo-bridged alkoxides yielded mixed metal oxide phases with lower surface areas.