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以硝酸稀土为原料,碳酸氢铵作沉淀剂,PVA为分散剂,通过控制一定的反应条件,制得易沉降、过滤的碳酸钆(铕),此前驱物在一定温度下焙烧即可得到Gd2O3:Eu纳米晶.通过红外光谱、差热-热重、X射线衍射、扫描电镜等多种分析测试方法,研究了碳酸钆(铕)的组成、分解过程,以及Gd2O3:Eu的形成过程、微观形貌和粒度.结果表明:前驱物碳酸钆(铕)在较低的温度(700℃)焙烧即可制得Gd2O3:Eu纳米晶的纯相,属立方晶系,颗粒呈球形.当焙烧温度从700℃升高到1000℃时,粒径从约50nm增大到70nm.对样品的激发光谱、发射光谱测定表明:Gd2O3:Eu纳米晶在265nm光激发下,发红光,发射光谱谱峰在611nm;与体材料相比,激发光谱中电荷迁移带(CTB)明显红移,从体材料的255nm移至265nm.
Using rare earth nitrate as raw material, ammonium bicarbonate as precipitating agent and PVA as dispersant, gadolinium carbonate (europium) which is easily settled and filtered can be prepared by controlling certain reaction conditions, and the precursor can be calcined at a certain temperature to obtain Gd2O3 : Eu nanocrystals.The composition and decomposition process of gadolinium carbonate (europium) and the formation process of Gd2O3: Eu were investigated by means of infrared spectroscopy, differential thermal-thermogravimetry, X-ray diffraction and scanning electron microscopy. Morphology and particle size.The results show that the pure phase of Gd2O3: Eu nanocrystal can be obtained by calcination of gadolinium carbonate (europium carbonate) at a relatively low temperature (700 ℃) From 700 ℃ to 1000 ℃, the particle size increased from about 50nm to 70nm. The excitation and emission spectra of Gd2O3: Eu nanocrystals showed red emission at 265nm and emission spectrum peaks At 611 nm, compared with the bulk material, the charge transfer band (CTB) in the excitation spectrum red-shifted significantly from 255 nm to 265 nm in the bulk material.