溶胶-凝胶法制备(Y_1-xEu_x)₂O₃发光薄膜及其发光性能研究

【作者】 程建良；

【导师】 曾冬铭；

【作者基本信息】 中南大学 ， 应用化学， 2004， 硕士

【摘要】 本论文综述了荧光粉的发展历史、现状、发展趋势及其现在先进的显示技术对新型荧光材料的要求。薄膜荧光材料是今后荧光材料研究的热点和发展趋势。 本文研究了以Y（NO₃）₃和Eu（NO₃）₃溶液作为起始原料，六次甲基四胺法和柠檬酸络合法制备稳定的溶胶，并分别采用测定透过率和粘度的方法来检测所制备的溶胶。在硅片上旋涂后热处理制得均匀而且致密的(Y_1-xEu_x)₂O₃薄膜。 对溶胶—凝胶法制备的(Y_1-xEu_x)₂O₃薄膜进行XRD、AFM、SEM及发光性能测试表明，在650℃下烧结3小时得到的(Y_1-xEu_x)₂O₃薄膜的结晶完好，这比高温固相法的结晶温度降低了200℃，薄膜结构致密，无孔隙，属于立方晶系。激发和发射光谱显示，在240～260nm激发强度非常大，最大激发峰在248nm处；在254nm激发下，在612.5nm处有窄的强峰发射。对Eu³⁺的发光机理作了分析阐述，其激发带主要是Eu³⁺与O^2-之间的CTS激发，而发射光谱是Eu³⁺的⁵D₀→⁷Fj（j=0、1、2、3、4）的跃迁发射。 对两种不同方法所制备的薄膜发光强度检测发现，柠檬酸络合法制备的薄膜发光强度只有六次甲基四胺法的73％。经过不同浓度的Eu³⁺掺杂的发光性能检测表明，用溶胶—凝胶法制备Y₂O₃：Eu³⁺时，掺杂浓度从常规高温固相法的6％提高到了8％。更多还原

【Abstract】 The development history, actuality and new trend of phosphors ,as well as the requirement of the advanced technology in display were summarized in the paper. The film materials will be the focus and the development trend in the research field of phosphors from now on.In this paper, transparent sols of yttrium oxide doped with various concentration of europium were prepared from inorganic precursors(yttrium nitrate and europium nitrate) with hexamethylene tramine and citric acid used as complexant respectively. Transmittance and viscosity of the sols were measured .The thin film of Y2O3:Eu were deposited by spin-coating method on silicon substrates and heated in the air at different temprature .The thin films were charactered by XRD, AFM and SEM. The results show that the films have been crystalled at 650 C for sintering 3 hours. Comparing with tranditional high-temperature synthesis, its temperature was reduced 200 C.The thin films are uniform and dense. They belong to cubic lattice.The luminescent mechanism of Y2O3:Eu3+ was analysed. The excitation spectrum of thin films show a wide band between 240nm to 260nm with a peak at 248nm, which is attributed to transition towards the charge transfer state(CTS) due to Eu-O interaction. The emission spectrum excited by 254nm consists of lines in the red spectral area. These lines correspond to transition from the excited 5Do level to 7FJ (J=0,1,2,3,4) level of the Eu3+ ion. The most intense line at 612nm corresponds to the hypersensitive transition between the 5D0 and 7F2 level of the Eu3+ ion.Finally, Compared with the emission intensity of the films ,the film prepared by citric acide method is 73 precent of that prepared by hexamethylene tramine method. The quenching concentration of Eu3+ increased from 6% to 8% by Sol-gel method.更多还原