摘要
以KOH和Nb2O5为原料,采用水热法制备了KNbO3粉体。采用X射线衍射(XRD)、扫描电镜(SEM)、红外光谱(FTIR)研究了KOH浓度和反应温度的变化对制备粉体的相组成及形貌的影响。研究发现水热温度为220℃、KOH的浓度为10mol/L时,可以合成出X射线衍射纯KNbO3晶体,所制备的晶体发育完整,为片状晶体,晶体尺寸为0.5～1.5μm。当水热温度为180℃、KOH的浓度为10mol/L时,制备的X射线衍射纯KNbO3晶体发育也很完整,大部分仍为片状晶体,有少量晶体呈狭长形状,晶体尺寸为0.5～1μm。当水热温度为180℃、KOH的浓度为6mol/L时,制备的X射线衍射纯KNbO3晶体发育完整,KNbO3晶体为片状,晶体大小较均匀,晶体尺寸为0.4～1μm,有部分晶体聚集成棒状,长度约为10μm。FTIR光谱表明所制备的样品出现了Nb=O和Nb-O-Nb的振动峰,反应温度的变化并未使这两个振动峰的位置发生明显的变化。
The potassium niobate were prepared with niobium pentoxide and potassium hydroxide as source materials by hydrothermal synthesis method. The product was characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). We also studied the effect of the concentration of potassium hydroxide solution and hydrothermal temperature on the component and morphology. The pure KNbO3 crystal could be prepared when it was synthesized at 220 oC and the concentration of potassium hydroxide solution was 10 mol/L. The as-synthesized crystal shows sheet shape with the size of 0.5-1.5 μm. When the concentration of potassium hydroxide solution was kept at 10 mol/L and the temperature was decreased to 180 oC, the product was still pure KNbO3 crystal with sheet shape and the size became 0.5-1 μm and some crystals also showed long and narrow morphology. The pure KNbO3 powder could be obtained at 180 oC when the concentration of potassium hydroxide solution was 6 mol/L, and the size of crystal was 0.4-1 μm. Some KNbO3 assemble the club-shaped crystal with the length of 10 μm. FTIR results indicate that the crystal showed Nb=O and Nb-O-Nb vibration peak. The reactive temperatures have no influence on the positions of the Nb=O and Nb-O-Nb peaks.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2010年第S2期487-489,共3页
Rare Metal Materials and Engineering
基金
深圳市科技计划项目(08CXY-21)
关键词
KNBO3
水热法
potassium niobate
hydrothrmal synthesis
