The effect of photo-irradiation in hydrolysis and condensation of silicon alkoxide

A silicon alkoxide-water-ethanol mixed solution was irradiated with ultraviolet rays, and the change of the silicon alkoxide molecular structure was evaluated by ²⁹Si nuclear magnetic resonance and Fourier transform infrared spectroscopies. Silicon alkoxide was hydrolyzed and the Si-OH bonds were produced by UV irradiation without any chemical catalyst for hydrolysis. The Si-O-Si bonds were also produced, and viscosity of the alkoxide solution became higher due to condensation of alkoxide.