SiO2 对Bi2O3-B2O3 玻璃体系光学、热学及结构的 影响

Glasses with compositions 50Bi<inf>2</inf>O<inf>3</inf>-xB<inf>2</inf>O<inf>3</inf>- (50-x)SiO<inf>2</inf>(x=0, 10, 20, 30, 40, 50) in mol% have been prepared by using a normal melt-quench technique. The effect of SiO<inf>2</inf> addition on thermal stability, optical properties and structural characteristic on Bi<inf>2</inf>O<inf>3</inf>-B<inf>2</inf>O<inf>3</inf> glass were systematically investigated by using XRD, DTA, ultraviolet-visible transmittance spectra, midinfrared transmittance spectra and Raman spectra. The experimental results demonstrate that, with the addition of SiO<inf>2</inf>, thermal stability of glass samples has been obviously improved. Once the amount of SiO<inf>2</inf> is too much, the glass samples tend to be phase seperation which results in the decrease of thermal stability. With increasing SiO<inf>2</inf> content, the UV cutoff edge firstly shifts to short-wave band and then shifts to long-wave band, and the transmittance of mid-infrared has been greatly improved. With substitution of SiO<inf>2</inf> for B<inf>2</inf>O<inf>3</inf>, the [BO<inf>3</inf>] triangles and [BO<inf>4</inf>] tetrahedral groups are gradually replaced by [SiO<inf>4</inf>]. [BiO<inf>6</inf>] octahedral and [SiO<inf>4</inf>] tetrahedral units are connected forming a vibrational mode of Bi-O-Si. The physical chemistry and optical performance of Bi<inf>2</inf>O<inf>3</inf>-B<inf>2</inf>O<inf>3</inf> glass were greatly improved by addition of SiO<inf>2</inf>.