Raman study of fluorine effects on silica with embedded SnO2 nanoparticles

Silica samples with embedded SnO2 nanoparticles have been produced by sol–gel method with a synthesis modified by the introduction of fluorinated silicon precursors. The structural features of silica network and SnO2 nanophase have been mapped inside the samples by means of confocal micro-Raman scattering spectroscopy. The results show that the detection of residual fluorine into the matrix as Si–F groups is accompanied by network dehydration, by intensity depletion of the D2 peak assigned to three-member rings of coordinated tetrahedra, and by SnO2 nanoparticles with much larger sizes than in fluorine-free material.