Aoyagi Takuya, Kohara Shinji, Naito Takashi, Onodera Yohei, Kodama Motomune, Onodera Taigo, Takamatsu Daiko, Tahara Shuta, Sakata Osami, Miyake Tatsuya, Suzuya Kentaro, Ohara Koji, Usuki Takeshi, Hayashi Yamato, Takizawa Hirotsugu
Hitachi Research Laboratory, Hitachi Ltd., 7-1-1 Omika, Hitachi, Ibaraki, 319-1292, Japan.
Tohoku University, 6-6-07 Aoba-yama, Sendai, Miyagi, 980-8579, Japan.
Sci Rep. 2020 Apr 28;10(1):7178. doi: 10.1038/s41598-020-63786-y.
Understanding the structure-property relationship of glass material is still challenging due to a lack of periodicity in disordered materials. Here, we report the properties and atomic structure of vanadium phosphate glasses characterized by reverse Monte Carlo modelling based on neutron/synchrotron X-ray diffraction and EXAFS data, supplemented by Raman and NMR spectroscopy. In vanadium-rich glass, the water durability, thermal stability and hardness improve as the amount of PO increases, and the network former of the glass changes from VO polyhedra to the interplay between VO polyhedra and PO tetrahedra. We find for the first time that the coordination number of oxygen atoms around a V is four, which is an unusually small coordination number, and plays an important role for water durability, thermal stability and hardness. Furthermore, we show that the similarity between glass and crystal beyond the nearest neighbour distance is important for glass properties. These results demonstrate that controlling the oxygen coordination and valence of the network-forming cation is necessary for designing the properties of glass.
由于无序材料缺乏周期性，理解玻璃材料的结构-性能关系仍然具有挑战性。在此，我们报告了基于中子/同步加速器X射线衍射和扩展X射线吸收精细结构（EXAFS）数据，并辅以拉曼光谱和核磁共振（NMR）光谱的逆蒙特卡罗模拟所表征的钒磷酸盐玻璃的性能和原子结构。在富钒玻璃中，随着PO含量的增加，耐水性、热稳定性和硬度提高，玻璃的网络形成体从VO多面体转变为VO多面体与PO四面体之间的相互作用。我们首次发现V周围氧原子的配位数为4，这是一个异常小的配位数，对耐水性、热稳定性和硬度起着重要作用。此外，我们表明，超出最近邻距离的玻璃与晶体之间的相似性对玻璃性能很重要。这些结果表明，控制网络形成阳离子的氧配位和价态对于设计玻璃性能是必要的。
