【作者】 崔元靖；

【导师】 王民权； 钱国栋；

【作者基本信息】 浙江大学 ， 材料学， 2005， 博士

【摘要】 随着信息时代的到来,高速光通讯,光信息处理以及光学存贮等领域已取得了飞速发展,非线性光学材料在上述领域的应用前景也得到越来越多的重视。无机—有机杂化非线性光学材料突破了传统无机、有机材料的界限,将有机非线性分子与无机基质在分子水平上融为一体,不仅兼有无机、有机材料两者的性能优势,并能够实现功能复合和协同优化,被认为是最有可能率先获得实际应用的新型非线性光学材料之一,已成为非线性光学与材料科学领域的一大研究热点。 本文简要介绍了非线性光学的基本原理与应用及生色团的分子设计理论,着重评述了无机—有机杂化非线性光学材料的种类、制备技术及其最新进展。在此基础上,针对不同器件的实用要求,设计、合成了一系列新型有机生色团分子及其功能化硅氧烷染料,并成功研制了多种性能优异的无机—有机杂化非线性光学材料;研究探索了生色团分子以及杂化非线性光学材料的设计思想、合成方法及其与宏观非线性光学性能的关联与控制;研究阐明了杂化材料中基质组成、结构与非线性性能的协同作用和调控规律;研究揭示了极化条件对杂化材料非线性光学性能的影响规律及其机理。 在生色团分子对硝基偶氮苯酚的基础上,设计合成了一系列具有良好透明性的生色团分子及其功能化硅氧烷染料,并用其研制出多种无机—有机杂化非线性光学薄膜。对薄膜制备中涉及的重氮—偶合反应、氨基甲酸酯反应以及溶胶—凝胶反应的关键制备工艺及其控制方法进行了深入研究与探讨,为提高材料的综合品质提供了依据。所有合成产物的化学结构都经过核磁共振、红外光谱和元素分析等得到了确证。紫外—可见光谱与溶剂变色法的计算结果表明在对硝基偶氮苯酚分子的共轭体系中引入电子给、受体并对其取代位置进行优化组合可以有效调节分子的线性与非线性光学性质,并能够在保持光学透明性与增大非线性光学性质两者之间获得较好平衡。使用红外光谱、扫描电镜、原子力显微镜、热重分析以及原位二次谐波研究分析了杂化薄膜的结构及其性能,结果表明,杂化薄膜有更多还原

【Abstract】 Over the past two decades, nonlinear optical （NLO） materials have been of great interest due to their potential applications in the fields of optical information processing, optical sensing, and telecommunications. Several chemical methodologies such as inorganic crystal, poled polymers and inorganic-organic hybrid materials have been developed. In the latter, the NLO chromophores are incorporated into the inorganic matrix by one or more covalent bonds. These hybrid materials capitalize on the unique properties offered by the two components to generate novel materials with desired characteristics, therefore, they are considered as promising candidate for NLO device applications and have been the subject of NLO materials research.In this thesis, the basic theories of NLO and molecular design theory are briefly introduced, the research progress of second order NLO materials are also reviewed. Research significance and recent progress of inorganic-organic hybrid NLO materials are summarized in detail, based on which, the prospect is looked forward.Four kinds of azobenzene type chromophores which exhibited high transparency in the blue range are synthesized and further react with 3-isocyanatopropyl-triethoxysilane （ICTES） to give alkoxysilane dyes via a urethane reaction. Followed by a sol-gel process of the alkoxysilane dyes, the inorganic-organic hybrid nonlinear optical （NLO） films are successfully prepared. Molecular structures of the resultants are confirmed by elemental analysis, FTIR and ¹H-NMR. The β_CDμ_g values of the chromophores are evaluated by solvatochromic method and the second harmonic coefficients (d₃₃) of the hybrid films are measured by in situ second harmonic generation （SHG） measurement, respectively. The effects of substituent group and position on β_CDμ_g values of thechromophores and J33 values of the films are discussed. The hybrid films exhibited large optical nonlinearity （J33 is 14.3 pm/V） and full transparency in the visible range, which imply that these films are hopeful for laser frequency-doubling in blue range.To meet the thermal stability requirement for electro-optic device application, a new inorganic-organic hybrid second-order NLO films is successfully prepared from a heterocycle chromophore containing benzothiazole unit. Molecular structures of the resultant are confirmed by elemental analysis, FTIR, UV-visible spectra and ’H-NMR. The largest da value of the poled film is 72.1 pm/V. This film exhibits excellent thermal stability of dipole alignment at elevated temperature. The SHG signal of the film has an onset temperature around 160 °C and a half-decay temperature at 215 °C. The (I33 value remains at 94% of its initial value after heating at 120 °C for 6 h.Two kinds of chromophores containing di-hydroxyethyl group are designed and synthesized, based on which, the cross-linked hybrid films are prepared. The da values of these films are 32.5 and 53.4 pm/V, respectively. After heating at 100 °C for 30 min, no obvious decay of the da value is observed, and after heating at 160 °C for 30 min, the d33 value remains at 74% of its initial value.A series of inorganic-organic hybrid films with different matrix are prepared by using TEOS, VTES and AMTES as precursors. The d33 values of the hybrid films increase with augmenting chromophore content, the largest chromophore content is 50 mol%, and the corresponding d^ value is 74.5 pm/V. The precursor AMTES is found to be effective for improving the thermal stability of optical nonlinearity due to the formation of hydrogen bonds between the carbonyl and aniline group, which is confirmed by virtue of FTIR and UV-Visible spectra.The poling process of the inorganic-organic hybrid film is investigated by in situ SHG measurement. An effective chromophore model was proposed to explain the change of SHG intensity in poling process. The structure and morphology of the hybrid film before and after poling are characterized by FTIR and SEM. The influence of poling temperature, poling voltage and poling time on SHG intensity and thermal stability are studied in detail. Based on the dipole model, the relation between polingvoltage and SHG intensity is obtained, which is in good agreement with the experimental results.更多还原