均相沉淀法論文稀土摻雜氧化物納米發(fā)光材料的制備與性能研究

1、均相沉淀法論文：稀土摻雜氧化物納米發(fā)光材料的制備與性能研究【中文摘要】稀土發(fā)光材料在平板顯示、綠色照明、光通訊及激光器件等領域有著廣泛應用。稀土氧化物是優(yōu)良的發(fā)光基質材料；而且,稀土摻雜納米發(fā)光材料表面包覆一層無摻雜的基質材料降低表面缺陷,對納米材料的發(fā)光性能具有一定的改善。本文采用均相沉淀法、水熱法和溶膠-凝膠法制備出了不同形貌的氧化物發(fā)光材料以及表面包覆基質的發(fā)光材料。獲得了一些有意義的研究結果：1.采用均相沉淀法成功的合成出均勻球形的Gd2O3:Eu3+發(fā)光材料和不同殼層厚度的Gd2O3:Eu3+Y2O3核-殼結構的發(fā)光材料,重點研究了Gd2O3:Eu3+表面包覆不同厚度的基質Y203后

2、對發(fā)光性的影響,發(fā)現(xiàn)當核層與殼層的厚度比R=4：1時的發(fā)光強度比未包覆的Gd2O3:Eu3+增強,認為核-殼型樣品降低了納米Gd2O3:Eu3+表面效應給發(fā)光強度帶來的負面影響。2.采用均相沉淀法成功的合成出了不同Eu3+摻雜濃度的球形Y2O3:Eu3+發(fā)光材料和不同摻雜濃度的Y203:Eu3+Gd203核殼結構發(fā)光材料。熒光光譜表明：Y2O3:Eu3+球形顆粒的表面包覆基質Gd2O3后,發(fā)光強度比未包覆的Y2O3:Eu3+增強,核殼結構粒子和單一粒子發(fā)光強度的差別與Eu3+離子的猝滅濃度有關。3.采用水熱法制備出了球形的YVO4:Eu3+發(fā)光材料,并用該法在其表面包覆基質材料GdVO4,形成

3、核殼結構的YVO4:Eu3+GdVO4發(fā)光材料。熒光光譜表明,YVO4:Eu3+表面包覆GdVO4之后,發(fā)射光強度比未包覆的YVO4:Eu3+曾強。4.(1)利用溶膠-凝膠法制備出了表面光滑的GdVO4:Eu3+粒子以及核殼結構的GdVO4:Eu3+GdVO4發(fā)光材料。包覆前直徑約310nm,包覆層厚度約45nm左右。(2)采用水熱法制備出了三明治結構的GdVO4:Eu3+以及核殼結構的GdVO4:Eu3+ YVO4發(fā)光材料,包覆前直徑約310nm,厚度約110nm左右。包覆層厚度為10nm。熒光光譜表明：以上兩種方法制備出的核殼結構的GdVO4:Eu3+LnVO4 (Ln=Gd,Y)發(fā)光強度

4、比未包覆的增強?！居⑽恼縍are earth luminescence materials are widely used in the fields of flat panel display, green lighting, optical communications and laser devices. Rare earth oxides are excellent matrixes for luminescent materials. Rare earth doped luminescent nanomaterials coated with a layer of undoped

5、 matrix materials can reduce surface defects of nanomaterials, which would improve the photoluminescence properties. In this dissertation, rare earth oxides luminescence nanomaterials with different morphologies were synthesized with homogeneous precipitation, hydrothermal and sol-gel method. Some m

6、eaningful results were obtained. The results were summarized as follows:1. Uniform spherical Gd2O3:Eu3+ luminescence nanomaterials with different Eu3+ doping concentration and Gd2O3:Eu3+Y2O3 core-shell structural composite particles with different shell thickness were prepared by homogeneous precipi

7、tation method. Photoluminescence properties of Gd2O3:Eu3+ nanoparticles coating with different thickness of Y2O3 host on the surface were mainly studied. It is found that when the coating thickness is suitable, that is Gd2O3:Eu3+/Y2O3 ratio of R=4:1, the luminescence intensities of core-shell partic

8、les are higher than that of the Gd2O3:Eu3+ core nanocrystals, it is thought that the core-shell samples decrease the negative effects of nanoparticles on the luminescence properties.2. Uniform spherical Y2O3:Eu3+ luminescence nanomaterials and Y2O3:Eu3+Gd2O3 core-shell structural composite particles

9、 with different Eu3+ doping concentration were prepared by homogeneous precipitation method. Photoluminescence properties show that the luminescence intensities of core-shell composite particles are higher than that of the Y2O3:Eu3+ core nanocrystals. It is thought that the intensity difference betw

10、een core-shell structure and un-coated nanoparticles was related to the quenching concentration of Eu3+3. Spherical YVO4:Eu3+ luminescence nanoparticles and YVO4:Eu3+GdVO4 core-shell structural composite particles were synthesized by hydrothermal method. Photoluminescence spectra show that the lumin

11、escence intensities of YVO4:Eu3+GdVO4 core-shell composite particles are higher than that of the YVO4:Eu3+ core particles.4. (1) GdVO4:Eu3+ and GdVO4:Eu3+GdVO4 luminescence materials with smooth surface were prepared by sol-gel method. The diameter of un-coated sample is 310 nm, and the thickness of

12、 coating layer is about 45 nm.(2) Sandwich structure GdVO4:Eu3+ and GdVO4:Eu3+YVO4 core-shell structural particles were prepared by hydrothermal method. The diameter of un-coated samples is 335 nm and the thickness is 110 nm. The thickness of coating layer is about 10 nm.Photoluminescence spectra sh

13、ow that the luminescence intensities of core-shell GdVO4:Eu3+LnVO4 (Ln=Gd, Y) composite particles are higher than that of GdVO4:Eu3+ core particles fabricated by the above two methods.【關鍵詞】均相沉淀法 水熱法 溶膠-凝膠法 核殼 納米發(fā)光材料 稀土氧化物 表面效應 濃度猝滅【英文關鍵詞】Homogeneous precipitation Hydrothermal method Sol-gel Core-she

14、l Huminescence nanomaterials Rare earth oxides Surface effect Concentration quenching【目錄】稀土摻雜氧化物納米發(fā)光材料的制備與性能研究摘要4-5ABSTRACT5目錄6-9第一章 緒論9-281.1 發(fā)光概述9-131.1.1 發(fā)光的基本原理91.1.2 稀土離子的能級和發(fā)光特性9-121.1.3 稀土離子的能量傳遞12-131.2 稀土納米發(fā)光材料的制備方法13-211.2.1 沉淀法14-151.2.2 水熱法15-181.2.3 溶膠-凝膠法18-201.2.4 微乳液法201.2.5 燃燒法201.2

15、.6 其他制備方法20-211.3 核殼結構的納米發(fā)光材料21-261.3.1 以稀土磷酸鹽為基質的核殼結構發(fā)光材料21-231.3.2 以稀土氟化物為基質的核殼結構發(fā)光材料23-251.3.3 以稀土氧化物為基質的核殼結構發(fā)光材料251.3.4 其他核殼結構的發(fā)光材料25-261.4 本文研究的目的和意義26-28第二章 實驗試劑、儀器及表征方法28-302.1 主要實驗試劑282.2 實驗儀器28-292.3 表征方法29-302.3.1 X射線衍射(XRD)分析292.3.2 傅立葉變換紅外光譜(FTIR)分析292.3.3 場發(fā)射環(huán)境掃描電子顯微鏡(FESEM)分析292.3.4 光電

16、子能譜(XPS)分析292.3.5 熒光光譜分析29-30第三章 Gd_2O_3:Eu(3+)和Gd_2O_3:Eu(3+)Y_2O_3發(fā)光材料的制備與發(fā)光性能30-393.1 概述303.2 實驗部分30-313.2.1 Gd_2O_3:Eu(3+)粒子的制備30-313.2.2 Gd_2O_3:Eu(3+)Y_2O_3復合粒子的制備313.3 結果與討論31-383.3.1 X射線衍射分析31-323.3.2 紅外光譜分析323.3.3 掃描電鏡分析32-353.3.4 光電子能譜分析35-363.3.5 熒光光譜分析36-383.4 本章小結38-39第四章 Y_2O_3:Eu(3+)和

17、Y_2O_3:Eu(3+)Gd_2O_3發(fā)光材料的制備與表征39-494.1 概述394.2 實驗部分39-404.2.1 不同摻雜濃度的Y_2O_3:Eu(3+)的制備394.2.2 不同摻雜濃度的Y_2O_3:Eu(3+)Gd_2O_3的制備39-404.3 結果與討論40-474.3.1 X射線衍射分析404.3.2 紅外光譜分析40-414.3.3 掃描電鏡分析41-444.3.4 光電子能譜分析44-454.3.5 熒光光譜分析45-474.4 本章小結47-49第五章 YVO_4:Eu(3+)和YVO_4:Eu(3+)GdVO_4發(fā)光材料的制備與表征49-575.1 概述495.2 實驗部分49-505.2.1 YVO_4:Eu(3+)粒子的制備49-505.2.2 YVO_4:Eu(3+)GdVO_4復合粒子的制備505.3 結果與討論50-565.3.1 X射線衍射分析505.3.2 紅外光譜分析50-515.3.3 掃描電鏡分析51-545.3.4 光電子能譜分析545.3.5 熒光光譜分析54-565.4 本章小結56-