Temporal Evolution of Diffusion Barriers Surrounding ZrTiO4 Nuclei in Lithia Aluminosilicate Glass-Ceramics

详细信息    查看全文

• 作者：Thomas H枚che ; Christian Patzig ; Thomas Gemming ; Roman Wurth ; Christian R眉ssel ; Isak Avramov
• 刊名：Crystal Growth & Design
• 出版年：2012
• 出版时间：March 7, 2012
• 年：2012
• 卷：12
• 期：3
• 页码：1556-1563
• 全文大小：627K
• 年卷期：v.12,no.3(March 7, 2012)
• ISSN：1528-7505

文摘

Glasses are usually synthesized by quenching a melt rapidly enough to avoid crystallization. Nanocrystalline materials can subsequently be derived from glasses by controlled crystallization with applying a tailored heat treatment. Upon the latter, nucleation agents are widely used to adjust the desired nanostructures. Nano glass-ceramics often possess intriguing properties. For example, they can be ultratransparent; that is, they hardly scatter light or possess thermal expansion coefficients very close to zero. Such properties have a high potential for future applications in optical devices. In this paper, the role of zirconia and titania used as nucleation agents in a lithia aluminosilicate glass is studied on the nanoscale using cutting edge analytical and imaging techniques performed using the transmission electron microscope. Precipitation of ZrTiO₄ nanocrystals [Bhattacharyya, S., et al. Nano Lett. 2009, 9, 2493] was found earlier to be accompanied by the formation of a circumjacent diffusion barrier consisting of alumina. In addition to this, here we study the temporal evolution of the alumina barrier and the size distributions of ZrTiO₄ nanocrystals and lithia aluminosilicate high-quartz solid solution crystals promoted by the nucleation agent. In the light of these findings, the theory of self-limited growth is refined.