Abstract
Phase formation of sodium bismuth titanate (Na0.5Bi0.5TiO3 or NBT) and its solid solution with barium titanate (BaTiO3 or BT) during the calcination process is studied using in situ high-temperature diffraction. The reactant powders were mixed and heated to 1000°C, while X-ray diffraction patterns were recorded continuously. Phase evolutions from starting materials to final perovskite products are observed, and different transient phases are identified. The formation mechanism of NBT and NBT–xBT perovskite structures is discussed, and a reaction sequence is suggested based on the observations. The in situ study leads to a new processing approach, which is the use of nano-TiO2, and gives insights to the particle size effect for solid-state synthesis products. It was found that the use of nano-TiO2 as reactant powder accelerates the synthesis process, decreases the formation of transient phases, and helps to obtain phase-pure products using a lower thermal budget.
| Original language | English |
|---|---|
| Pages (from-to) | 1330-1338 |
| Number of pages | 9 |
| Journal | Journal of the American Ceramic Society |
| Volume | 100 |
| Issue number | 4 |
| DOIs | |
| State | Published - Apr 1 2017 |
| Externally published | Yes |
Funding
This work was performed in part at the Analytical Instrumentation Facility (AIF) at North Carolina State University, which is supported by the State of North Carolina and the National Science Foundation (award number ECCS-1542015). The AIF is a member of the North Carolina Research Triangle Nanotechnology Network (RTNN), a site in the National Nanotechnology Coordinated Infrastructure (NNCI). D.H. thanks financial support of China Scholarship Council. E.A. acknowledges support from the Japan Society for the Promotion of Science. The authors thank Hanhan Zhou, Emily Lichtenberger, and Birgit Andersen for the thermogravimetric measurements.
Keywords
- X-ray methods
- heat treatment
- perovskites