【摘要】 采用水解氧化法制备Y₂O₃稀土材料,其工艺特点是先将稀土钇与石墨在真空感应炉中熔炼得到碳化钇合金,再经水解、热处理后即可得到Y₂O₃粉末.采用X射线衍射（X-ray diffration,XRD）等测试手段对所制备的Y₂O₃粉末的组成、微观结构和荧光性能等进行了研究,得到以下结果:将碳化钇合金研碎成1 mm左右的颗粒,并与去离子水按质量浓度比为1∶20配置,将PEG-400与去离子水按体积比为8∶100比例配置,放置于磁力恒温搅拌器上,在25?C下搅拌24 h后抽滤、洗涤,在80?C烘箱中烘干后得到Y（OH）₃粉末,最后经过400～1 000?C热处理后得到Y₂O₃粉末.碳化钇合金水解后得到的Y（OH）₃粉末经过400?C热处理后得到PDF卡片编号为No.65-3178的立方晶型Y₂O₃,但需要继续加热到800?C后才具有荧光性能.由此工艺制得的Y₂O₃荧光粉在激发波长为355 nm的氙光照射下,在430～600 nm波长范围内分别在468和578 nm处有明显的荧光峰出现,且所发的光为蓝白光.样品的发光机理是由于C元素在Y₂O₃晶格中形成COOY和C—OY这两种结构断裂后,所引起的光电子耦合所致.更多还原

【Abstract】 A novel and convenient hydrolysis and oxidation method is used in preparing Y₂O₃ powders.In this work,yttrium carbide was obtained from yttrium and the graphite by melting in a vacuum melting furnace.Y₂O₃ powders were prepared with a hydrolysis and oxidation method.The composition,crystal structure,photoluminescence properties,morphology and microstructure of Y₂O₃ powders were investigated with X-ray diffration（XRD）,etc.The following results had been obtained.The triturated alloys sized about 1mm were introduced into deionized water with 1∶20 mass ratios and PEG-400 and deionized water with 8∶100 volume ratio under agitation for 24 h at 25℃.After filtering,washing and deionized water drying in a cabinet at 80℃,and 400～1 000?C heat treatment,Y₂O₃ powders were obtained.Crystallization peaks appeared around 400℃.These XRD data were entirely consistent with the PDF card No.65-3178,showing that the samples were cubic Y₂O₃.When the annealing temperature was raised to 800℃,the sample exhibited fluorescence.The obtained powders showed good bluish-white PL emissions,ranging from 430 to 600 nm,with peaks at 468 and 578 nm,under xenon light excitation.The luminescent mechanism was ascribed to the breakage of C—OY and COOY structures,giving rise to photoluminescence through a strong electron-photon coupling.更多还原