QQ客服 官方微博 反馈留言

题名	N31型掺钕磷酸盐激光玻璃水解的X射线光电子能谱研究
作者	李萌
学位类别	硕士
答辩日期	2015
授予单位	中国科学院上海光学精密机械研究所
导师	陈伟
关键词	掺钕磷酸盐激光玻璃 水解 X射线光电子能谱 化学稳定性
其他题名	Study on the Water Durability of N31 Nd-doped Phosphate Laser Glass with X-ray Photoelectron Spectroscopy
中文摘要	磷酸盐激光玻璃具有激活离子掺杂浓度高，热膨胀系数低，熔制温度低，易于制成大尺寸玻璃等优点，成为当前激光惯性约束核聚变装置的增益介质。然而受到P5+中3d轨道电子的影响，磷酸盐玻璃中磷氧四面体的整体连接程度较低，这降低了磷酸盐玻璃的化学稳定性，使其易被工作或贮存环境中的水所侵蚀并产生表面微裂纹。此类缺陷将降低激光玻璃的抗损伤阈值，并影响聚变激光驱动器的通量。本文围绕N31型掺钕磷酸盐激光玻璃的水解反应，通过电感耦合等离子体发射光谱、X射线光电子能谱、拉曼光谱、红外光谱等表征手段，开展对其水解过程、水解机理等方面的理论与实验研究。 第一章主要介绍了磷酸盐玻璃的应用、性质与结构，其中通过对二元磷酸盐玻璃结构的详细讨论，引出在现阶段研究中被普遍采用的磷酸盐玻璃结构模型。除此之外，本章还综述了磷酸盐玻璃水解研究的现状。 第二章主要介绍了本实验中所使用的研究方法与其理论基础，包括样品的制备以及各种仪器的测试。在本章中，较为详细的介绍了电感耦合等离子体发射光谱、X射线光电子能谱的理论基础与仪器构成，并讨论了本实验中所采用的测试参数。拉曼光谱与红外光谱的基本原理以及测试参数在本章中也有所提及。 第三章是本文的核心部分，详细研究了N31型掺钕磷酸盐激光玻璃在水解过程中表面的成分、结构变化，并以此为基础分析了N31型激光玻璃在纯水溶液中水解的反应机理与反应过程。首先，通过电感耦合等离子体发射光谱测试水溶液中各离子浓度随水解时间的变化，分别对N31型激光玻璃的短期水解和长期水解进行分析，表明该玻璃在纯水溶液中表现出非化学计量的水解方式，并且在水解反应初期阶段离子交换为主要反应机理。然后，以X射线光电子能谱为主要分析手段，对N31型激光玻璃表面成分、结构随水解时间的变化进行表征，表明在水解过程中玻璃表面的桥氧含量不断下降，铝氧含量不断上升，而磷氧四面体则发生降解。另外，在一段时间的水解之后，玻璃表面可能出现Al3+、Ba2+等离子的沉积。之后，以拉曼光谱与红外光谱为分析手段，进一步证明磷氧四面体在水解过程中的不断降解。最后，通过对前述表征的分析与总结，提出N31型激光玻璃总体的水解过程。 根据表面氧磷含量比随水解时间的变化，N31型激光玻璃的水解过程包括三个阶段。第一阶段水解以离子交换反应为主，在该阶段中，玻璃表面的氧磷含量比、桥氧比例、磷氧四面体种类均基本保持不变，而水溶液中磷离子浓度则表现出与水解时间的t1/2的关系；第二阶段水解以P-O-P结构的解链反应为主，伴随着磷氧四面体的迅速降解，表现为表面氧磷含量比升高，桥氧比例降低，铝氧比例升高，而水溶液中磷离子浓度则表现出正比于水解反应时间的关系，磷氧四面体的降解也被拉曼与红外光谱所证实；第三阶段水解以磷氧四面体网格的慢速降解与表面沉积反应为主。 论文的第四章是对本实验所有研究结果的总结，并指出了研究中存在的不足和需要进一步改进的地方。
英文摘要	With the properties of higher ion doped concentration, lower thermal expansion, lower melting temperature, as well as the mature access for large-scale glass, phosphate laser glass is selected for the current high-peak-power laser glass. However, due to the influence of the electron on P5+ 3d orbit, the overall connectivity of phosphate tetrahedras is relatively low. This structure property limits the chemical durability of phosphate glass, making it vulnerable to water from working and storage conditions and then results in the microcrack on the glass surface. This defect will reduce the threshold for laser damage of the glass, as well as decrease the laser flux of the inertial confined fusion laser facility. In Chapter I, the usages, properties and structure of phosphate glass are introduced. With the detailed discussion on the structure of binary phosphate glass, the structural model, which is nowadays widely accepted in the research of phosphate glass, is introduced. Moreover, the research status on the hydrolization of phosphate glass is also reviewed in this chapter. In Chapter II, the research methods and basic theories of this study are introduced, including the sample preparation and the testing methods. In this chapter, the basic theories and instrumental structure of inductively coupled plasma optical emission spectroscopy and the X-ray photoelectron spectroscopy are discussed in detail. The testing parameters for these two characterizations are also introduced. In addition, in this chapter we present the basic theories and testing parameters for Raman and infrared spectroscopy briefly. Chapter III is the core content of this dissertation. In this chapter, the evolution of surface composition and structure during the hydrolization of N31 Nd-doped phosphate laser glass are researched in detail. On this basis, we analyze the mechanisms and courses of the hydrolization of N31 Nd-doped phosphate laser glass. Firstly, the ionic concentration in the leached solution is measured by inductively coupled plasma optical emission spectroscopy. As is shown in both short-term and long-term hydrolization, the N31 glass shows an incongruent dissolution behavior in pure water, and the main hydrolization mechanism during the initial reaction is the ion exchange process. Secondly, with the assistance of the X-ray photoelectron spectroscopy, we characterize the surface evolution of N31 laser glass during the hydrolyzation process. The XP spectra show that, the proportion of bridging oxygen decreases, the proportion of Aluminum-oxygen escalates, and the P-tetrahedra will degrade during the hydrolyzation process. Moreover, with the hydrolization of a period of time, the Al3+ and Ba2+ may precipitate on the glass surface. Thirdly, with the analysises of Raman and infrared spectra, the degradation of the P-tetrahedra is furtherly proved. In the end, we analyze and summarize all the characterization results, and introduce an overall hydrolization process for the N31 laser glass. Based on the evolution of surface O/P ratio, the hydrolization process of N31 laser glass involves three stages. The first stage is controlled by the ion exchange mechanism. In this stage, the O/P ratio, the proportion of bridging oxygen, and the species of the P-tetrahedras remain constant. Moreover, the concentration of P5+ in the leached solution shows an t1/2 dependence with the hydrolization time. The second stage is controlled by cleavage of P-O-P connections, with the degradation of the P-tetrahedras, the increase of the O/P ratio, the decrease of the proportion of bridging oxygen, and the escalate of the proportion of the Aluminum-oxygen. Besides, the P5+ concentration in the leached solution is proportional to the reaction time. The degradation of P-tetrahedras is also shown by the Raman and IR spectra. The third stage is coupled with the gradual degradation of P-tetrahedras and the precipitation on the glass surface. Chapter IV is the summarization of all the results in this dissertation. Besides, we point out the deficiencies in this research, as well as issues that need further studying.
语种	中文
内容类型	学位论文
源URL	[http://ir.siom.ac.cn/handle/181231/16917]
专题	上海光学精密机械研究所_学位论文
推荐引用方式 GB/T 7714	李萌. N31型掺钕磷酸盐激光玻璃水解的X射线光电子能谱研究[D]. 中国科学院上海光学精密机械研究所. 2015.

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。