煅烧温度对钛酸钡晶相的影响

Effect of Calcining Temperature on Crystal Phase of BaTiO3

采用溶胶-凝胶法，制备钛酸钡干凝胶。通过DSC对其进行热分析，确定两个煅烧温度：780℃和900℃。通过DSC，XRD对这两种温度煅烧得到的钛酸钡进行晶相结构表征。结果表明，随着煅烧温度升高，晶粒尺寸逐渐增大，（111）面间距d（111）和a轴逐渐减小，c轴逐渐增大。说明可以通过提高煅烧温度得到常温下为铁电性的四方相钛酸钡晶体，解决了溶胶-凝胶法制备钛酸钡在常温下为顺电性的立方相晶体这一问题。

The BaTiO3 xerogel powders were prepared through sol-gel method and calcined at different temperatures with the analysis of the DSC of BaTiO3 xerogel. Their crystal phases were characterized by XRD and DSC. Results show that with the increase of calcining temperature, the grain becomes larger and d（111）and an axis becomes shorter while c axis becomes longer gradually. It also indicates that the tetragonal ferroelectric phase of BaTiO3 can be prepared by increasing the calcining temperature.