标题:
层状晶体结构铌酸盐KNb3O8粉体的凝胶–燃烧法合成与表征Synthesis of KNb3O8 Powders with Layered Structure by a Gel-Combustion Method
作者:
袁晓曼, 张俊计, 武斌, 张琼, 陶霜
关键字:
层状结构, KNb3O8, 凝胶–燃烧法Layered Niobate; KNb3O8; Gel-Combustion
期刊名称:
《Material Sciences》, Vol.2 No.2, 2012-04-26
摘要:
本文以水合氧化铌(Nb2O5•nH2O)为铌源,硝酸钾(KNO3)为钾源,采用柠檬酸凝胶–燃烧法合成了层状结构铌酸盐KNb3O8粉体。采用同步热分析仪(TG/DSC)分析了前驱体粉末的热分解过程。借助X射线衍射(XRD)和扫描电镜(SEM)对合成样品的物相组成及微观形貌进行了表征。结果表明,在600℃时KNb3O8开始结晶,粉体呈规则的条状。随着煅烧温度的升高,KNb3O8粉体的结晶度提高,形貌由条状逐渐过渡为类片状。
The niobate (KNb3O8) powders with layered structure were successfully synthesized via the citric acid gel-combustion process using KNO3 and Nb2O5•H2O as the raw materials. Thermal behavior of the precursor was determined by TG-DSC techniques. The phase composition and morphology of the synthesized samples were characterized by using the X-ray diffraction and scanning transmission electron microscope. It was found that KNb3O8 phase was crystallized directly from the amorphous precursor at about 600˚C. The SEM images of the samples showed that the particles were bar-like under calcination temperature of 600˚C. However, the morphology of the particles transformed into flakes gradually as the calcination temperature increasing.