本文選題：TiO2 + 稀土摻雜��； 參考：《吉林大學(xué)》2015年博士論文

【摘要】：在過去的數(shù)十年中，因?yàn)橄⊥翐诫s的納微米材料在熒光粉、先進(jìn)平板顯示器、生物和化學(xué)標(biāo)簽等領(lǐng)域具有潛在的應(yīng)用價值，所以它們受到了研究學(xué)者的廣泛關(guān)注。TiO2作為半導(dǎo)體材料中應(yīng)用最廣的一種，它具有特殊的晶體結(jié)構(gòu)、高折射率、低聲子能量、足夠的熱學(xué)和環(huán)境穩(wěn)定性等特點(diǎn)，因此將其用作稀土摻雜的主體材料已經(jīng)被廣泛的研究。眾所周知，材料的物理、化學(xué)性質(zhì)和其形貌密切相關(guān)，因此可控的合成具有特定尺寸、維度和結(jié)構(gòu)的TiO2納微米功能材料已經(jīng)成為了當(dāng)前的研究熱點(diǎn)之一。 本論文用水熱和溶劑熱法合成了多種形貌的稀土摻雜TiO2納微米材料，通過X射線衍射儀、傅里葉紅外光譜儀、掃描電子顯微鏡、透射電子顯微鏡、和選區(qū)電子衍射儀等手段對樣品進(jìn)行了表征測試。此外，通過熒光光譜系統(tǒng)的研究了各種稀土摻雜TiO2納微米材料的發(fā)光機(jī)理和影響樣品發(fā)光性能的因素。主要的研究工作包括以下幾個方面： 1、以檸檬酸和乙二胺作為晶面控制劑，通過一種容易的水熱合成路線制備了具有高結(jié)晶度和形貌一致的TiO2:Eu3+紡錘形納米棒。實(shí)驗(yàn)結(jié)論表明檸檬酸和乙二胺的加入量能夠明顯的影響所得樣品的形貌和尺寸。在最佳實(shí)驗(yàn)條件下所得的納米棒為紡錘形結(jié)構(gòu)，中心直徑為60nm，長度為460nm。在紫外光激發(fā)下，未經(jīng)過后續(xù)煅燒處理的TiO2:Eu3+紡錘形納米棒顯示紅光發(fā)射，這對應(yīng)于Eu3+的5D0-7F2躍遷。以相同的激發(fā)波長激發(fā)兩種不同形貌的TiO2:Eu3+樣品，可以發(fā)現(xiàn)TiO2:Eu3+紡錘形納米棒比TiO2:Eu3+納米粒子具有更高的發(fā)光強(qiáng)度。這主要是由于納米粒子相比納米棒具有更多的表面缺陷引起的。此外，通過低溫位置選擇光譜證明了Eu3+在TiO2晶體中處于無序的表面位置。 2、通過簡單的水熱法制備了一種新穎的三維（3D）花狀TiO2:Eu3+微球。經(jīng)過隨后的高溫煅燒過程（500oC，3h），其花狀形貌能夠完整的保持，且能得到具有高結(jié)晶度的銳鈦礦晶相。掃描電鏡圖像顯示，所得的三維花狀TiO2:Eu3+微球樣品表面呈現(xiàn)寬松多孔的花狀結(jié)構(gòu)，并且是由不規(guī)則形狀的表面光滑的納米片交叉組裝而成，納米片的厚度大約為10nm。根據(jù)所得樣品的掃描電鏡圖像發(fā)現(xiàn)，檸檬酸（H3Cit）、乙二胺（En）和氫氟酸（HF）在花狀微球的形成過程中起到至關(guān)重要的作用。此外，在紫外光激發(fā)下，煅燒后得到的三維花狀TiO2:Eu3+微球樣品展現(xiàn)了優(yōu)良的紅光發(fā)射，這對應(yīng)于Eu3+的5D0-7F2躍遷發(fā)射。 3、以碳球?yàn)橛材０�，鈦酸四丁酯為鈦源，乙醇為溶劑，聚乙烯吡咯烷酮為分散劑，硝酸釤為釤源，通過一種簡單的溶劑熱法制備了C@TiO2:Sm3+核殼微球，在電阻爐中煅燒得到TiO2:Sm3+空心球。XRD結(jié)果顯示，在500°C煅燒2h所得的TiO2:Sm3+空心球?yàn)殇J鈦礦相。透射電鏡顯示，，樣品為尺寸均一的空心球結(jié)構(gòu)，空心球內(nèi)徑為55-75nm，殼層厚度為10-14nm。在紫外光激發(fā)下，TiO2:Sm3+空心球發(fā)射出特有的橙紅色光，這與Sm3+的特征發(fā)射（4G5/2-6H7/2）相一致。此外，TiO2:Sm3+空心球的發(fā)光強(qiáng)度與Sm3+的摻雜濃度密切相關(guān)，當(dāng)Sm3+的摻雜濃度為2mol%時，TiO2:Sm3+空心球有最強(qiáng)的熒光發(fā)射。 4、用EDTA作為螯合劑，通過一種簡單方便的水熱法成功制備了三維TiO2和TiO2:Eu3+核殼微球。XRD結(jié)果顯示，經(jīng)過水熱反應(yīng)得到的樣品不需經(jīng)過煅燒就表現(xiàn)為銳鈦礦晶相。所得產(chǎn)物由許多不規(guī)則形狀的直徑為0.5-1.5μm的核殼微球組成。這種核殼微球的比表面積達(dá)到了134.32m2/g，遠(yuǎn)遠(yuǎn)高于P25的比表面積(50±15m2/g)。表面積大導(dǎo)致樣品具有大量的表面缺陷，因此在紫外光激發(fā)下，由于能量經(jīng)過非輻射躍遷的損失使TiO2:Eu3+核殼微球幾乎不發(fā)光。然而，在紫外光的照射下，TiO2核殼微球?qū)谆人芤壕哂辛己玫墓獯呋到庑Ч�，遠(yuǎn)遠(yuǎn)強(qiáng)于常用的光催化劑P25。這與樣品具有大的表面積密切相關(guān)，大的表面積使樣品表面具有更多的表面活性位點(diǎn)并能夠吸附更多的染料分子。因?yàn)槠渚哂袃?yōu)良的光催化活性，所以在降解廢水中的有機(jī)染料方面有廣闊的應(yīng)用前景。
[Abstract]:Over the past few decades, rare earth doped nanofilms have potential applications in the fields of phosphors, advanced flat panel displays, biological and chemical labels, so they have been widely concerned by researchers as one of the most widely used.TiO2 materials, with special crystal structure, high refractive index, and high refractive index. Low phonon energy, sufficient thermal and environmental stability, so it has been widely studied as the main material of rare earth doping. It is well known that the physical and chemical properties of the materials are closely related to their morphology. Therefore, the TiO2 nano functional materials with specific dimensions, dimensions and structures have become the present. One of the hotspots of research.
In this paper, a variety of rare earth doped TiO2 nanometer materials were synthesized with water heat and solvothermal method. The samples were characterized by means of X ray diffractometer, Fourier infrared spectrometer, scanning electron microscope, transmission electron microscope, and electoral electron diffractometer. The mechanism of luminescence and the factors affecting the luminescence properties of TiO2 doped nanmicron materials are mainly studied.
1, with citric acid and ethylenediamine as the crystal control agent, the TiO2:Eu3+ spindle shaped nanorods with high crystallinity and the same morphology were prepared through an easy hydrothermal synthesis route. The experimental results show that the addition of citric acid and ethylenediamine can obviously affect the shape and size of the obtained samples. The rice rod is a spindle shaped structure with a center diameter of 60NM, and the length of 460nm. is excited by ultraviolet light, and the TiO2:Eu3+ spindle nanorods without subsequent calcinations show red light emission. This corresponds to the 5D0-7F2 transition of Eu3+. With the same excitation wavelength, two different morphologies of TiO2: Eu3+ samples can be excited, and TiO2:Eu3+ spinning nanorods can be found. The luminescence intensity is higher than that of TiO2:Eu3+ nanoparticles. This is mainly due to the more surface defects of nanorods than nanorods. In addition, the location of Eu3+ in the TiO2 crystal is proved to be in a disordered surface by the low temperature position selective spectroscopy.
2, a novel three-dimensional (3D) flower like TiO2:Eu3+ microsphere was prepared by a simple hydrothermal method. After the subsequent high temperature calcination process (500oC, 3H), the flower morphology of the microspheres could be kept intact and the crystalline phase of anatase with high crystallinity was obtained. The scanning electron microscope images showed that the surface of the three-dimensional flower like TiO2:Eu3+ microspheres showed loose surface. The porous, flower like structure is formed by the cross assembly of irregular surface smooth nanoscale. The thickness of the nanoscale is about 10nm., according to the scanning electron microscope images of the obtained samples, the citric acid (H3Cit), the ethylenediamine (En) and the hydrofluoric acid (HF) play a vital role in the formation of the flower shaped microspheres. The three dimensional flower like TiO2:Eu3+ microspheres samples prepared by calcination showed excellent red emission, corresponding to the 5D0-7F2 transition emission of Eu3+.
3, using carbon sphere as a hard template, four butyl titanate as a titanium source, ethanol as a solvent, polyvinylpyrrolidone as a dispersant, samarium nitrate as a samarium source, C@TiO2:Sm3+ nuclear shell microspheres were prepared by a simple solvent heat method. The result of the calcined TiO2:Sm3+ hollow sphere.XRD results in a resistance furnace showed that the TiO2:Sm3+ hollow spheres obtained from the calcined 2h of 500 degree C were anatase. The transmission electron microscope shows that the sample is a homogeneous hollow sphere structure, the inner diameter of the hollow sphere is 55-75nm, the shell thickness is 10-14nm. excited by the ultraviolet light, the TiO2:Sm3+ hollow sphere emits unique orange red color light, which is in accordance with the characteristic emission of Sm3+ (4G5/2-6H7/2). In addition, the luminescence intensity of the TiO2:Sm3+ hollow sphere is closely related to the doping concentration of Sm3+. Cut correlation, when the doping concentration of Sm3+ is 2mol%, the TiO2:Sm3+ hollow spheres have the strongest fluorescence emission.
4, using EDTA as a chelating agent, three dimensional TiO2 and TiO2:Eu3+ core shell microspheres have been successfully prepared by a simple and convenient hydrothermal method. The results show that the samples obtained by hydrothermal reaction are anatase phase without calcination. The product is composed of a number of irregular shaped nuclear shell microspheres with a direct diameter of 0.5-1.5 micron. The core shell is a core shell. The specific surface area of the microspheres reached 134.32m2/g, far higher than the specific surface area of P25 (50 + 15m2/g). The large surface area caused the samples to have a large number of surface defects. Therefore, under ultraviolet light, the TiO2:Eu3+ nuclear shell microspheres were almost not luminescent due to the loss of energy through the non radiation transition. However, under ultraviolet light, the TiO2 core shell microspheres were used. Methyl orange aqueous solution has a good photocatalytic degradation effect, far stronger than the common photocatalyst P25. which is closely related to the large surface area of the sample. The large surface area makes the surface of the sample more surface active site and can adsorb more dye molecules. Because of its excellent photocatalytic activity, the wastewater is degraded in the wastewater. The organic dyes are widely used in the future.

【學(xué)位授予單位】：吉林大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2015
【分類號】：TB383.1;O614.411

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 單爽;吳昊;譚明乾;馬小軍;;稀土上轉(zhuǎn)換熒光納米材料的制備與生物應(yīng)用[J];生物化學(xué)與生物物理進(jìn)展;2013年10期

本文編號：1796849