Synthesis of monodisperse mesoporous TiO2 spheres with tunable sizes between 0.6 and 3.1 μm and effects of reaction temperature, Ti source purity, and type of alkylamine on size and monodispersity.

We report a novel method for synthesizing monodisperse mesoporous TiO(2) spheres (sizes = 0.6-3.1 μm) by hydrolysis of titanium isopropoxide (TIP) in a mixture of C(8)-C(16)n-alkylamine, water, and ethanol. The size increases with decreasing temperature, TIP concentration, and water concentration, and upon purifying TIP. n-Dodecylamine gives the highest monodispersity.