| Abstract
| - One-pot self-assembled hybrid films were synthesized by the cohydrolysis of methyltriethoxysilaneand tetraethoxysilane and deposited via dip-coating. The films show a high “defect-free” mesophaseorganization that extends throughout the film thickness and for domains of a micrometer scale, as shownby scanning transmission electron microscopy. We have defined these films defect-free to describe thehigh degree of order that is achieved without defects in the pore organization, such as dislocations ofpores or stacking faults. A novel mesophase, which is tetragonal I4/mmm (space group), is observed inthe films. This phase evolves but retains the same symmetry throughout a wide range of temperatures ofcalcination. The thermal stability and the structural changes as a function of the calcination temperaturehave been studied by small-angle X-ray scattering, scanning transmission electron microscopy, and Fouriertransform infrared spectroscopy. In situ Fourier transform infrared spectroscopy employing synchrotronradiation has been used to study the kinetics of film formation during the deposition. The experimentshave shown that the slower kinetics of silica species can explain the high degree of organization of themesostructure.
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