Preparation and structural properties of Cu-Zn-Al-oxides: a comparative study between the hydrodynamic-cavitational and classical route

Series of Cu-Zn-Al oxides have been prepared using a mixture of aqueous Na2CO3 and NaOH solutions for precipitation to investigate the influence of these agents on the formation of the precipitates and, subsequently, on the structure of the oxides. Two synthesis routes are applied, one classical in a well stirred beaker and a second one using a cavitational device. Differences in phase compositions, crystallite sizes and strain are observed for the calcined materials. One further series was performed varying solvent, precipitation agents and pH. The controlled production of crystallite sizes in a range from 5 to 10 nm and the insertion of strain into the material have been verified. The cavitational preparation route offers new fundamental insights in the formation of this important mixed oxide system and favours investigations in direction of the design of nanoscopic materials. The results are discussed in terms of cavitational effects and compared to results obtained from classical experiments. (C) 2003 Kluwer Academic Publishers.