论文标题:纳米氧化锆（ZrO_2）材料的发光机制及光学特性研究
The Luminescence of Nano-sized ZrO_2 and Its Optical Characters
论文作者 江昕
论文导师 李福利,论文学位 硕士,论文专业 光学
论文单位 首都师范大学,点击次数 118,论文页数 54页File Size2184k
2002-05-01论文网 http://www.lw23.com/lunwen_577971277/ 纳米氧化锆;固体发光;吸收和跃迁;微波;超声;亲水性;亲油性
nano-sized ZrO_2,photoluminescence(PL),microwave,ultrasonic,hydrophilic,oleophilic
20世纪80年代末诞生并发展起来的纳米科学技术有可能成为21世纪的主导技术。纳米材料具有许多传统材料无法媲美的奇异特性和特殊功能，在各行各业中将有空前的应用前景。氧化锆作为陶瓷材料的一种，其特殊的发光机制及在不同波长激光光束照射下发生的亲水性亲油性的转化特性，近年来吸引了众多研究者的兴趣。氧化锆(ZrO_2)纳米微粒由于其特殊的光电特性和潜在的应用前景吸引着更多的关注。这些应用前景如光学器件的制造与改善，电化学电容电极，氧气传感器，燃料，催化剂(包括光催化)以及新型陶瓷材料等等。 本论文的主要结果： (1)用超声法和微波法，分别制备出稳定的四方相的氧化锆纳米微粒。用X射线衍射、透射电子显微镜测试，发现氧化锆纳米颗粒结晶良好，粒径较小，分布均匀，退火前平均粒径为1.0-2.0nm。 (2)对于超声法制备的氧化锆纳米微粒，用波长254nm激发光激发，得到的发射光谱较宽，其中两个较明显的峰在458nm和482nm处；用波长为412nm的激发光激发，得到的发射光谱在550nm-625nm之间，峰值在615nm处。 (3)对于微波法制备的氧化锆纳米微粒，用波长为254nm激发光激发，发射光谱峰值在402nm、420nm和459nm；用波长为412nm激发光激发，得到的发射光谱有两个较为明显的峰，分布位于530nm和608nm处，其中608nm处发光相对强度远高于530nm处的发光相对强度。对于超声法与微波法制备的样品荧光光谱产生差别的机理，也进行了分析讨论。 (4)对于氧化锆材料在一定波长激光光束照射下发生亲水性亲油性的转化特性，也进行了初步实验。 论文共有六章，引言主要对纳米材料光学机制研究的意义，纳米氧化锆的发光特性，以及固体发光理论作了概述。 第一章是固体发光理论部分，对固体材料尤其是半导体材料的发光从理论上建立基础。 第二章对纳米材料的特性进行探讨，侧重讨论与传统材料不同的性质，详细 纳米巩化钻发光机制及光学特付汕X 总结了纳米尺度对材料发光性能的影响。 第三、四章是论文的核心部分。第三章是实验部分，在纳米氧化铬材料的制 备上，为了得到较好的样品，采用微波及超声这两种手段制备，并使用X射线 衍射以＊D）、透射电子显微镜（＊＊M）、荧光光谱＊L（N。N1u加nescence）对 产品的物化特性进行了表征。在第四章中，对前一章的得到的实验结果进行了讨 论，重点在于建立理论模型，对纳米氧化铅材料的发光光谱进行解释，并对纳米 半导体材料光学特性的理论模型的建立进行了初步探索。 第大章是补充实验部分，由于氧化钳薄膜在不同波长激光光束照射下能发牛 余水性来汕性的转化，可应用到计算机直接制版技术卜。使川溶胶一凝胶法制折 双化钻纳米微粒，采用浸涂法将之涂抹在钢板卜，迫火后重复浸涂过札1，攸测板 表而氧化钻腆达到一定厚度。使用YA G激光器照射，用表而角测量仪观察照射 部分朵水亲汕性的转化。 第六章是结征语，对本论文进行总结，并对今后的研究方向提出建议。
Nanoscale physics and technology, developed from the early 1980s, will be the leading technology in the near future. Since nanoscale materials take much more advantages than traditional materials, they will be applied to many kinds of industrial fields. As an ordinary ceramic material, Zr O2 has many special characters in luminescence. Moreover, when a surface of zirconia ceramic is exposed to a laser under controlled conditions, this area is transformed from a hydrophilic to an oleophilic state, the same condition occurs in the counter procedure. This special character is intriguing more and more researchers in recent years. Nanometric ZrO2 powders are a technologically important class of materials with a wide range of applications and the powders with narrow size distribution are intensively sought as raw materials for advanced ceramics. These applications including optical devices and electrochemical capacitor electrodes, oxygen sensor, fuel cells, photocatalysts and advanced ceramics, etc.Summarize: there are several conclusions in this thesis:(1) Under room temperature, we got stabled tetragonal nanometric ZrO2 powder synthesized by microwave-irradiation and ultrasonic respectively.We utilized XRD, TEM to characterize these nano- ZrOi samples, we found it is clear that these samples are crystal and distributed well, and the average particle diameter is 1.0-2.0nm (before annealed).(2) We utilized PL spectra (Photoluminescence spectra) to characterize the samples synthesized by microwave-irradiation. When the samples were excited by 254nm ray, we got a widen emission luminescence band, there are two clear crests corresponded to 458nm and 482nm; When the samples were excited by 412nm ray, the emission luminescence band is between 550nm and 625nm, and the crest is 615nm.(3) We also utilized PL spectra (Photoluminescence spectra) to characterize the samples synthesized by ultrasonic. When the samples were excited by 254nm ray, the emission luminescence band is corresponding to three crests: 402nm, 420nm, 459nm; When the samples were excited by 412nm ray, the two clear crests are 530nm and 608nm, and the relative intensity of 608nm crest is much higher than the 530nm crest. The cause of the photoluminescent difference between naon-ZrO2 synthesized by microwave and ultrasonic wasalso discussed in the thesis.(4) In order to validate the special character of ZrO2 that the transformation between a hydrophilic state and an oleophilic state when the surface of zirconia ceramic is exposed to a laser under controlled conditions, we have done some experiments.This thesis is composed of seven sections, including the introduction, which give a brief introduction to the significance of studying nanoscale materials" luminescent characters and the theory of solid materials luminescence.Chapter one is the theoretical part of solid materials luminescence, in this section, we discuss the theoretical model of solid materials luminescence, especially semiconductors.Chapter two offers a particular discussion on the special characters of nano-sized materials, especially on the difference between traditional materials and nanoscale materials. We also discuss luminescent effects caused by the nanometer.Chapters three and four are the kernel of this thesis. Chapter three is a detailed presentation about experiments we have taken, in order to get good samples, we took two simple methods for the preparation of stabilized ZrO2 nano-powders. We utilize XRD (X-ray diffraction), TEM(Transmission Electron Microscope) and PL spectra(Photoluminescence spectra) to characterize these samples. In Chapter four, we analyze the photoluminescence(PL) excitation and emission spectra of the nano-ZrC>2 powders and focus on offering a reasonable interpretation about the luminescent characters of ZrOa nanocrystal. Moreover, we explore on setting up the theoretical model of other oxide nanocrystals" luminescent procedures.Chapter five is the complementary experiment of the research on luminescent mechanism
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