Mechanism of Surfactant Removal from Ordered Nanocomposite Silica Thin Films by Deep-UV Light Exposure

摘要

In recent years, methods have been developed for the generation of complex ordered nanocomposite materials through organic templating of inorganic structures. One approach involves preparation of composite materials by an evaporation induced self-assembly process involving organization of organic surfactants and formation of inorganic silica from soluble precursors. Recently, we have shown that deep-UV light (185-254nm) is efficient at removing the surfactant microphase for a routine production of well-ordered mesoporous silica thin films. Here we probe the evolution of surfactant removal from nanocomposite thin film silica inesophases as a function of deep-UV exposure using a combined application of FTIR and single wavelength ellipsometry. Taken together, these data indicate that surfactant removal occurs in a step-wise fashion with the formation of oxidized intermediates prior to complete removal of the surfactant from the thin film.