Effect of thermal annealing on structures and properties of Yb3+/Al3+/P5+ co-doped silica glasses

Publication date: 15 October 2019Source: Journal of Non-Crystalline Solids, Volume 522Author(s): Mengting Guo, Chongyun Shao, Feng Shi, Fan Wang, Shikai Wang, Chunlei Yu, Lei Zhang, Jinjun Ren, Lili HuAbstractHomogeneous 89.9SiO2-4Al2O3-6P2O5–0.1Yb2O3/Eu2O3 glasses were fabricated via a sol−gel method and sintered under vacuum at high temperature, and subsequently they were annealed at 850 °C for 15 and 75 h. Effect of thermal annealing time on structures and properties of glasses was systematically investigated. Solid state nuclear magnetic resonance (SSNMR) and Raman scattering spectra were employed to characterize the network structures. Pulse electron paramagnetic resonance (EPR) techniques and the emission and excitation spectra of Eu3+ ions were used to study the local environment of Yb3+ ions. SSNMR and Raman results indicate that AlPO4 units increase at the expense of AlV, AlVI and P(3) groups after annealing. The glass network structures have a significant influence on density and refractive index. EPR and Eu3+ spectra indicate an increase in Al around Yb3+ ions and a reduction in the asymmetry degree of Yb3+ ligands. A correlation between structures and properties of glasses is developed.
Source: Journal of Non Crystalline Solids - Category: Chemistry Source Type: research