摘要
以K-Nb-H2O三元体系为研究系统,在Lencka-Riman热力学模型的框架内,对水热法合成KNbO3粉体进行了理论设计,得到了体系稳定产出相图和优化的合成条件包括反应温度、反应物浓度和溶液的pH控制等重要信息.研究结果表明,前驱物浓度和pH调节(矿化剂KOH浓度)是形成纯相KNbO3必需的条件.在此基础上,利用简单的五氧化二铌和KOH做前驱物,在523K反应温度,高强碱性溶液条件下,常规水热法成功合成了纯相的KNbO3粉体.实验研究和理论设计十分吻合.
In the framework of Lencka–Riman thermodynamic model,we studied on the theoretical design for synthesis of KNbO3 powder by hydrothermal processing in the K-Nb-O system.As the result of the calculations,stability and yield diagrams of the investigated system were obtained.Thus,the optimum conditions(i.e.,temperature,synthesis precursor concentrations,solution pH) for the hydrothermal synthesis of phase-pure KNbO3 were presented.The calculated results suggested that the concentrations of precursors and pH-adj...
出处
《襄樊学院学报》
2008年第2期18-22,51,共6页
Journal of Xiangfan University
关键词
水热合成
KNBO3
热力学模型
稳定产出相图
Hydrothermal synthesis
KNbO3
Thermodynamic model
Stability and yield diagrams