有机共轭荧光材料的结构设计、合成及性能研究

发布时间：2018-01-20 06:11

本文关键词： 有机共轭荧光材料光致发光电致变色聚噻吩衍生物 BODIPY荧光化合物钝化剂　出处：《南京大学》2017年博士论文　论文类型：学位论文

【摘要】：有机共轭荧光材料具有光电性能优异、环境友好和生物相容性好等优点,在电致变色、化学/生物传感器、有机太阳能电池、生物医学成像和离子检测等领域有着广泛的应用。此外,有机共轭荧光材料还具有物理化学性质稳定、结构易于修饰和容易加工等特点,由此引起了科学界更广泛的研究兴趣。设计并制备结构新颖和综合性能优异的有机共轭荧光材料已经成为当前荧光材料领域的研究热点之一。本论文以聚噻吩和BODIPY衍生物作为研究对象,对有机共轭荧光材料的设计、合成及其光学、电化学等相关性质进行了系统研究。在合成含噻吩和吲哚结构的共轭寡聚物及其光致发光和电致变色性质的研究、含吲哚的BODIPY荧光物质的合成及其性质研究以及尺寸可调的光致发光聚吡咯纳米微球/点的制备及其性质研究等方面进行了探索,并取得了如下研究结果:(1)含噻吩和吲哚结构的共轭寡聚物的合成及其光致发光和电致变色性质的研究设计合成了一系列具有吲哚和噻吩结构的新型功能单体及其对应的寡聚物,通过NMR、GPC、FTIR和TGA确认了它们的结构。研究结果表明,增加共轭聚合物的吲哚数量和密度以及延长吲哚部分N上烷基链的长度可影响共轭结构的π-π堆积相互作用,从而降低能隙和导致不同的光谱现象,同时可提高这些寡聚物的热稳定性。这些结果给我们提供了一个有效的方法来预测、调整分子轨道能级并进而合成具有优良发光性能的荧光材料。基于寡聚物P3的电致变色器件显示出新颖的电致变色现象,随电压增加呈现出红、黄、绿和棕褐色的四种颜色变化,表明其具有作为优异电致变色材料的潜力。此外,P3在Zn2+的选择性检测方面表现出优良的灵敏性,在作为化学荧光传感试剂方面也具有潜在的应用价值。(2)含吲哚的BODIPY荧光化合物的合成及其性质研究设计合成了一系列BODIPY的8-位含有吲哚结构的新型功能荧光化合物c1-c6,通过NMR、FTIR和MS确认了它们的结构。对c3和c5的晶体结构解析和光谱性质测试表明,反向平行的BODIPY核心结构使c3分子之间存在着一定程度的π-π相互作用,提高了荧光量子效率;c5由于噻吩环的引入与吲哚环形成大的平面结构,使其与BODIPY核心结构之间的二面角变小,导致噻吩环和吲哚环的自由旋转程度变大,分子内电子的振动弛豫过程和能量内转换消耗能量变多,从而降低了荧光量子效率。制备得到的BODIPY化合物在不同极性溶剂里的测试结果和结构分析表明,正溶致动力学效应、供吸电子效应、空间位阻效应和溶剂化作用等因素共同导致它们具有不同的荧光量子效率和光谱现象。理论计算和CV结果表明,吸电子基团有利于降低化合物的能隙;供电子基团有利于提高化合物的能隙。由于NO2和NH2的影响,c3和c6对pH的变化比较敏感,其余的c1、c2、c4和c5在不同pH条件下都比较稳定,这可归结于c1、c2、c4和c5这四个化合物中吲哚环上的N与化合物母体上与B原子配位后的N相比,更易于发生质子化和去质子化反应;此外,F原子与BODIPY核心结构之间形成的氢键会抑制强碱性条件下对氟硼配位的破坏也是原因之一。所制备的BODIPY化合物具有物理化学性质稳定、生物毒性低以及荧光强度的对数与化合物所处溶剂粘度的对数呈良好的线性关系等特点,在细胞成像方面表现出很好的应用效果,有望在细胞显影和测试细胞内粘度变化从而进行疾病诊断等方面体现其实际应用价值。(3)尺寸可调的光致发光聚吡咯纳米微球/点的制备及其性质研究利用m-CPBA作为氧化剂,以乙醇作溶剂,成功地制备了直径为20nm的聚吡咯纳米球。所制得的聚吡咯纳米球具有发射波长依赖激发波长的特点和在不同的离子条件下物理化学稳定性好的优点。通过不同结构的钝化剂如PEG2000、TTDDA和EDA对其表面功能化以后,荧光量子效率从最初的2.2%分别提高到了3.1%、13.3%和 40%。TEM、DLS、UV和CV的结果表明,经过 PEG2000、TTDDA和EDA对聚吡咯纳米球的表面钝化后,可以分别得到相应的直径为5.5 nm、4.5 nm和3 nm的纳米点,并且降低的样品的粒子尺寸与降低的能隙和增加的荧光寿命相一致。所制备的聚吡咯纳米球/点具有物理化学性质稳定、抗光漂白能力强和生物毒性低等特点,在细胞成像和荧光墨水方面表现出很好的应用效果,有望在相关方面的高科技领域体现其实际应用价值。
[Abstract]:Organic conjugated fluorescent material has excellent photoelectric performance, good compatibility and environmental friendly creatures in electrochromic, chemical / biological sensors, organic solar cells, the field of biomedical imaging and ion detection has been widely used. In addition, organic conjugated fluorescent material has stable physical and chemical properties, the structure is easy to modify and easy the processing characteristics of the resulting research interest to the wider scientific community. The design and preparation of novel structure and excellent properties of organic conjugated fluorescent material has become one of the hot researches in the field of fluorescent material. In this paper, polythiophene and BODIPY derivatives as the research object, the design of organic conjugated fluorescent material, and its synthesis the optical and electrochemical properties were studied. The polymers containing thiophene and indole synthesis of conjugated oligomeric structure and its photoluminescence and electrochromic Study on color properties, BODIPY fluorescent material containing indole synthesis and its properties and size tunable photoluminescence of polypyrrole nanoparticles / preparation and properties research aspects are explored, and the results obtained are as follows: (1) the synthesis of conjugated oligomers containing thiophene and indole dimer and its structure photoluminescence and electrical design on the photochromic properties of the synthesis of a series of indole and thiophene structure of novel functional monomers and their corresponding oligomers, through NMR, GPC, FTIR and TGA confirmed their structure. The results show that the increase of the density and quantity of indole conjugated polymers and extend the indole part N the length of alkyl chain can affect the conjugate structure of Pi Pi stacking interactions, thus reducing the gap and lead to different spectrum phenomenon, also can improve the thermal stability of these oligomers. These results provide us An effective method to predict, adjust the molecular orbital and synthesis of fluorescent material has excellent luminescent properties. The oligomers of P3 electrochromic devices exhibit novel electrochromic phenomena based on the show red, with the increase in the voltage of four kinds of yellow, green and brown color change, shows as excellent electrochromic materials potential. In addition, P3 showed excellent sensitivity in the selectivity of Zn2+ detection, but also has potential applications in chemical sensing. As fluorescence reagent (2) synthesis and Properties Study on the design of BODIPY fluorescent compounds containing indole synthesis a series of BODIPY 8- containing indole structure new functional fluorescent compounds by NMR, FTIR and C1-C6, MS confirmed their structure. The crystal structure analysis and spectral properties of C3 and C5 tests show that the BODIPY core structure of antiparallel C3 molecules Between there is a certain degree of pi pi interactions, improve the fluorescence quantum efficiency; C5 due to the introduction of thiophene ring and the indole ring formation plane structure, the dihedral angle between BODIPY core structure and smaller, cause the spin degree of freedom thiophene ring and indole ring change, intramolecular vibrational relaxation of electrons relaxation process and energy conversion energy consumption, thereby reducing the fluorescence quantum efficiency. The test results in different polar solvents and structure analysis of BODIPY compounds prepared showed positive solvatokinetic effect, for the electron withdrawing effect, steric effect and solvent effect and other factors cause them to have different the fluorescence quantum efficiency and spectral phenomenon. The theoretical calculation and the results of CV showed that the electron withdrawing groups can help to reduce the gap compound; electron donating group is conducive to the improvement of energy gap compounds. Due to NO2 and NH2. Ring, is more sensitive to changes in C3 and C6 to pH, the rest of the C1, C2, C4 and C5 in different pH conditions are relatively stable, and it can be attributed to C1, C2, C4 and C5 of the four compounds N and compounds indole ring on the matrix and B atoms after compared to N it is easy to occur, the protonation and deprotonation reaction; in addition, formed between the F atom and the BODIPY core structure of the hydrogen will suppress the strong alkaline conditions of fluorine boron coordination failure is one of the reasons. The preparation of BODIPY compounds with stable physical and chemical properties, low toxicity and logarithm and the fluorescence intensity of the compounds the solvent viscosity showed a good linear relationship and other characteristics, showing good application effect in cell imaging, is expected to change in the viscosity of cells developing and testing cells to diagnose the disease and other aspects reflect its practical value. (3) light adjustable size induced Light / polypyrrole nanoparticles preparation and properties using m-CPBA as oxidant, with ethanol as solvent, was prepared successfully with diameter of polypyrrole nanospheres 20nm. The polypyrrole nano ball with emission wavelength depend on the excitation wavelength and advantages in ion under the conditions of different physical and chemical stability of the through the structure of different passivation agents such as PEG2000, TTDDA and EDA on the surface of functionalized fluorescent quantum efficiency were increased from the initial 2.2% to 3.1%, 13.3% and 40%.TEM, DLS, UV and CV showed that, after PEG2000, TTDDA and EDA on the surface passivation of polypyrrole nanoparticles can be obtained, respectively the diameter of 5.5 nm, 4.5 nm and 3 nm nano, and reduced the particle size and reduce the consistent gap and the increase of the fluorescence lifetime. The polypyrrole nanospheres prepared with chemical / physical It has stable properties, strong resistance to photobleaching and low toxicity. It shows good application results in cell imaging and fluorescent ink. It is expected to reflect its practical application in related high-tech fields.

【学位授予单位】：南京大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TQ422

【相似文献】