高掺杂稀土PBA玻璃的制备及其化学稳定性研究

The preparation and chemical durability study of high doped rare earth PAB glass

稀土掺杂磷酸盐玻璃具有优异的光学和光谱特性,在激光介质材料、有色滤光材料等领域中有着重要的应用。在研究P2O5-BaO-Al2O3-Sm2O3(PBAS)玻璃形成能力的基础上,借助NMR、红外吸收光谱等分析手段,研究了玻璃的结构特点以及在各种化学介质条件下玻璃的化学稳定性能、玻璃的组成和结构对化学稳定性的影响。结果表明:玻璃结构主要由磷氧四面体[PO4]3-和铝氧八面体[AlO6]3-构成;Al3+含量越高,玻璃结构越稳定,玻璃的耐水性和耐酸性也越好;玻璃结构中阳离子的极化能力越强,玻璃的耐酸性越好,侵蚀过程中玻璃表面形成的“缺碱层”在一定程度上减缓了化学介质的侵蚀程度;在碱性介质中,磷酸盐长链末节的金属离子被水化,产生P—O—P断键,形成正磷酸盐溶解到溶液中,稀土离子含量的增加,在一定程度上恶化了玻璃的耐碱性能。

The phosphate glasses doped with rare earth ions have been widely used in laser mediums and optical filter materials for their outstanding optical and spectrum characteristics. The structure and its effect on the chemical durability, under different chemical solutions, based on Sm2O3 doped PAB （P2O5-Al2O3-BaO） glasses were investigated by MAS NMR, FT-IR and other technical methods systemically. The results shows that the main structure unit of PBAS glass is [ PO4 ] and [AlO6 ] ; with the increasing of Al^3＋ and Sm^3＋ content, the structure of glass tends to more stability, and the water resistance performance is more excellent; the corrosion of glass in acid media depends on the polarize ability （Z^2/r）, the acid resistance performance can be improved when the Z^2/r is increasing, moreover, the dissolution rate decreases because of a hydrated layer. The corrosion mechanism of glass in alkali media is that the metal ions of phosphate long chain are hydrated; the P-O-P bond is disentangled and dissolved in the form of orthophosphate. The results display that with the increasing of Sm^3＋ ions, the alkali resistance performance decreases.