A Sucrose-Mediated Sol-Gel Technique for the Synthesis of MgO-Y^sub 2^O^sub 3^ Nanocomposites

A sucrose-mediated aqueous sol-gel procedure was developed to synthesize MgO-Y^sub 2^O^sub 3^ nanocomposite ceramics for potential optical applications. The synthesis involves the generation of a precursor foam containing Mg2+ and Y3+ cations via the chemical and thermal degradation of sucrose molecules in aqueous solution. Subsequent calcination and crushing of the foam gave MgO-Y^sub 2^O^sub 3^ nanocomposites in the form of thin mesoporous flake-like powder particles with uniform composition and surface areas of 27-85 m^sup 2^ g^sup -1^, depending on calcination conditions. The flakes exhibited a homogeneous microstructure comprising intimately mixed nanoscale grains of the cubic MgO and Y^sub 2^O^sub 3^ phases. This microstructure was resistant to grain coarsening with average grain sizes of less than 100 nm for calcination temperatures of up to 1200°C. The results indicate that the sucrose-mediated sol-gel process is a simple effective method for making nanoscale mixed oxides. [PUBLICATION ABSTRACT]