Sol-gel synthesis of monolithic tin-doped silica glass

The preparation of Sn-doped SiO 2 glasses with different Sn contents (Sn/(SiO 2 + SnO 2 ) ratio 0.01 to 10.0% w/w) was performed by two sol–gel routes. The first route (method A) used tin(IV) tert-butoxide as the tin precursor and in the presence of acetylacetone it resulted in transparent glasses with a maximum tin content of 0.1%. The precursor in the second route (method B) was dibutyltin diacetate; this was more efficient and transparent glasses of up to 1% tin content were obtained. As electron paramagnetic resonance can identify paramagnetic E′ Sn centres, defects that form when silica glass is subjected to X-ray irradiation, we assessed the tin centres that substituted silicon in the silica network.At higher tin contents (Sn ≥ 3%), method B gave crystalline nanosized particles of SnO 2 (6–10 nm) dispersed throughout the silica matrix.

[1]  J. Livage,et al.  Sol‐Gel Chemistry from Metal Alkoxide Precursors , 1991 .

[2]  C. Askins,et al.  Photoinduced grating and intensity dependence of defect generation in Ge‐doped silica optical fiber , 1992 .

[3]  G. Spinolo,et al.  Tin doped silica by sol–gel method: doping effects on the SiO2 Raman spectrum , 1998 .

[4]  A. E. Geissberger,et al.  Raman studies of vitreous Si O 2 versus fictive temperature , 1983 .

[5]  G I Stegeman,et al.  Correlation of defect centers with a wavelength-dependent photosensitive response in germania-doped silica optical fibers. , 1991, Optics letters.

[6]  K. Yu,et al.  MICROSTRUCTURAL CHANGE OF NANO-SNO2 GRAIN ASSEMBLAGES WITH THE ANNEALING TEMPERATURE , 1997 .

[7]  F. L. Galeener,et al.  Band limits and the vibrational spectra of tetrahedral glasses , 1979 .

[8]  Y. Qian,et al.  Study of the Raman spectrum of nanometer SnO2 , 1994 .

[9]  E. Friebele,et al.  Oxygen-associated trapped-hole centers in high-purity fused silicas , 1979 .

[10]  F. Babonneau,et al.  Chemical modification of alkoxide precursors , 1988 .

[11]  Clément Sanchez,et al.  Sol-gel chemistry of transition metal oxides , 1988 .

[12]  Linards Skuja,et al.  Isoelectronic series of twofold coordinated Si, Ge, and Sn atoms in glassy SiO2: a luminescence study , 1992 .

[13]  B. G. Potter,et al.  Photosensitivity in germano-silicate sol-gel thin films , 1994 .

[14]  D. Hand,et al.  Photoinduced refractive-index changes in germanosilicate fibers. , 1990, Optics letters.

[15]  M. Hampden‐Smith,et al.  Solid state and solution structural investigation of homoleptic tin(IV) alkoxide compounds. Part I. Sn(O—t-Bu)4 and [Sn(O—i-Pr)4•HO—i-Pr]2 , 1991 .

[16]  C. A. Murray,et al.  Intrinsic surface phonons in amorphous silica , 1979 .

[17]  G. Spinolo,et al.  Identification of Sn variants of the E' center in Sn-doped SiO 2 , 1998 .

[18]  K. Hill,et al.  Photosensitivity in optical fiber waveguides: Application to reflection filter fabrication , 1978 .

[19]  Victor Mizrahi,et al.  248 nm induced vacuum UV spectral changes in optical fibre preform cores: support for a colour centre model of photosensitivity , 1993 .

[20]  Shiv k. Sharma,et al.  Raman investigation of ring configurations in vitreous silica , 1981, Nature.

[21]  B. E. Yoldas.  Monolithic glass formation by chemical polymerization , 1979 .

[22]  Simon Poole,et al.  Photolytic Index Changes in Optical Fibers , 1993 .

[23]  F. L. Galeener.  Planar rings in glasses , 1982 .