Sm_2O_3掺杂对BaO-B_2O_3Al_2O_3-SiO_2玻璃形成及结构的影响

EFFECT OF Sm_2O_3 DOPED ON FORMATION AND STRUCTURE OF BaOB_2O_3Al_2O_3SiO_2 GLASS

借助魔角旋转核磁共振技术,探讨掺Sm2O3后BaOB2O3Al2O3SiO2(BBAS)玻璃(BBASS玻璃)的形成、结构及热处理条件下玻璃结构的变化情况。研究表明:随着稀土掺量的增加,BBASS玻璃的形成区域先扩大后缩小。在Sm2O3外掺摩尔分数为30%时BBASS玻璃具有最大的形成区域。在BBAS玻璃结构中,随着BaO含量的增加,硼氧三角体[BO3]逐渐向[BO4]转变,原先[AlO4],[AlO5],[AlO6]共存的铝氧多面体结构逐渐转变为大量[AlO4]和少量[AlO5]共存的结构。在BBASS玻璃结构中,随着Sm2O3掺入量的增加,Sm2O3对铝氧多面体结构变化的影响与BaO类似;对硼氧多面体而言,Sm3+强大的积聚作用使玻璃结构中硼氧多面体形成了巨大的网络。以上差异说明了Al3+比B3+更容易进入稳定的四面体结构。热处理对玻璃结构影响甚微。

The glass formation, structure and the structure change effected by heat-treatment of BaO-B2O3-Al2O3-SiO2 （BBAS） system doped with Sm2O3 （BBASS） glasses ware investigated by the magic angle spinning nuclear magnetic resonance spectroscopy technology. It is found that, the glass forming region of BBASS glasses expanded firstly than shrunken subsequently, with the content of rare earth oxide increasing. While the extra addition of Sm2O3 reached to 30% in mole, the largest glass forming region is attained. In the structure of the BBAS glass, with the addition of BaO, [BO3] gradually transforms into [BO4], and the aluminum coordination occurred in the structure gradually transforms from co-existing [AlO4], [AlO5] and [AlO6] to the co-existence of mainly [AlO4] and less [AlO5]. In the structure of the BBASS glasses, the Sm2O3 has the similar effect as BaO on the alumina coordination sites. While Sm^3＋ accumulates the boron network because of its high field strength, forming a large network structure. Aluminium ion is prior to B^3＋ to enter the stable structure of tetrahedron. Heattreatment has little effect on the glass structure.