Photoinduced High-Quality Ultrathin SiO 2 Film from Hybrid Nanosheet at Room Temperature

Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
Journal of the American Chemical Society (Impact Factor: 12.11). 10/2008; 130(36):11848-9. DOI: 10.1021/ja803852w
Source: PubMed


The paper describes a flexible approach to building up high-quality ultrathin SiO2 films under deep UV light irradiation at room temperature. The ultrathin hybrid nanosheet possessing polyoctahedral silsesquioxane (POSS) has been designed to prepare densely packed ultrathin POSS films by the Langmuir-Blodgett (LB) technique. The LB technique enables POSS to have a multilayered structure with nanoscale precision. The films' hardness and modulus changed considerably from 0.1 and 2.6 GPa to 1.7 and 32.2 GPa, respectively, after deep UV light irradiation. Subsequent FTIR measurements revealed that the organic components were removed completely and that the POSS cage structure turned to an Si-O-Si network structure. X-ray photon spectroscopy also confirmed high-quality SiO2 formation with no suboxides.

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