An IR-spectroscopic study of solid solutions in the systems, Ce2Si2O7 ? Y2Si2O7 and La2Si2O7 ? Y2Si2O7

Solid state reactions of nanocrystalline Ce0.5Yb0.5O1.75 mixed oxide with high surface area silica in oxidizing and reducing atmosphere

“…Formation of A-type Ce 2 Si 2 O 7 as a first silicate phase in the mixed oxide-silica systems contrasts with pure CeO 2 -SiO 2 system, where I-Ce 2 Si 2 O 7 disilicate occurred first at around 1000 1C[16]. We could not find in the literature information on mixed disilicates containing exclusively lanthanide ions, though there are a few works on (Y-Ln) 2 Si 2 O 7 systems, where Ln¼ lanthanide[31,32,46,47,48]. Mixed (Y-Ln) 2 Si 2 O 7 silicates, where Ln¼Gd, Yb, Lu, prepared by ceramic method, i.e., solid state reaction of crystalline oxides (Ln 2 O 3 , Y 2 O 3 and SiO 2 ) at high temperatures, were studied by Maier et al…”

“…Andreev et. al., [48] reported IR-spectroscopic studies on Ce 1 À x Y x Si 2 O 7 mixed silicates obtained at 1450-1500 1C in reducing atmosphere. Similarly to our findings they observed for certain content of smaller Y 3 þ ions, x 41.6, sudden change in IR spectra indicating phase transformation from high temperature G-Ce 2 Si 2 O 7 into A-form, which at this temperature is a stable polymorph for lanthanides with ionic radius smaller than Ce 3 þ .…”

Optical properties of Ce-doped SiO2 films: From isolated Ce3+ ions to formation of cerium silicate

“…According to the literature [21,22], these peaks can be attributed to the formation of a cerium silicate phase, most probably Ce 2 Si 2 O 7 . This compound shows luminescence around 400 nm [21,15] which is compatible with our PL measurements (Fig.…”

Observation of a nanoscale phase separation in blue-emitting Ce-doped SiO1.5 thin films

“…The intensity of this band increases as the Ce content in the films increases, thus suggesting that this feature is related to the presence of Ce. In the literature, 24,25 several closely spaced peaks have been identified in the range 826-975 cm À1 , which may be due to the formation of the Ce 2 Si 2 O 7 or Ce 4.667 (SiO 4 ) 3 O compounds. Our FTIR investigations thus confirm the formation of a cerium silicate for high annealing temperatures.…”