烷基化富勒烯衍生物自组装及光电应用探索

发布时间：2018-11-12 12:53

【摘要】：目前,富勒烯研究是材料科学的一个前沿领域。富勒烯自身的结构特性和光电性能受到学界的瞩目,因此富勒烯的研究主要集中在自组装微纳结构以及有机太阳能电池方面。而烷基化富勒烯衍生物的自组装不同于富勒烯本身的自组装过程。由于烷基的引入,富勒烯碳笼的空间对称性受到破坏,同时取代基之间的相互作用进一步影响了富勒烯碳笼间的π-π堆积作用,因此新型烷基化富勒烯衍生物的合成,自组装及光电性能的研究是一个全新的课题。本文考察烷基化富勒烯衍生物的结构、溶液浓度、溶剂种类等因素对可控形貌的合成及光电性质的影响。首先我们设计并合成了四种不同结构的烷基化富勒烯衍生物,对产物进行了质谱(MS)、核磁氢谱(1HNMR)来确定分子结构。纯化的样品被用作自组装实验,内容包括:不同衍生物浓度,不同溶剂体系等因素对烷基化富勒烯衍生物自组装的影响。扫描电镜(SEM)测试显示烷基链在富勒烯分子上的位置变化对烷基化富勒烯自组装存在一定的影响。烷基链处于间位位置的烷基化富勒烯衍生物C60-m-hexyl较难得到规则形貌结构,而烷基链处于对位位置的C60-p-hexyl容易自组装形成规则的微结构。同时与C60相比较,烷基化富勒烯形成的形貌都是以片层为基础构建形成的形貌,而裸C60分子则容易自组装形成规则的体型结构。在溶剂对自组装的影响方面,烷基化富勒烯衍生物在良溶剂CCl4体系中较容易生成花或球状结构,而对应不良溶剂其碳链长度可以影响生成形貌的大小,SEM测试发现在CCl4体系中随着不良溶剂碳链的增长,所形成的形貌尺寸逐渐减小。在C60-p-hexyl与C60共组装的实验中,得到了与两者单独自组装截然不同的形貌结构。对于烷基化富勒烯光电性能的探索,紫外可见吸收光谱显示四种烷基化富勒烯相比于C60具有更强的光吸收能力。通过电化学测试显示烷基化富勒烯衍生物具有良好的氧化还原可逆性。最后将C60-m-hexyl,C60-p-hexyl,C60-p-octyl、C60-p-hexylph四种衍生物应用于有机太阳能电池中,C60-m-hexyl作为受体材料的有机太阳能电池存在光电转换性能。
[Abstract]:At present, fullerene research is a frontier field in material science. The structure and photoelectric properties of fullerene have attracted much attention, so the research of fullerene is mainly focused on self-assembled micro-nano structure and organic solar cells. The self-assembly of alkylated fullerene derivatives is different from the self-assembly process of fullerene itself. Because of the introduction of alkyl, the space symmetry of fullerene carbon cage is destroyed, and the interaction between substituents further affects the 蟺-蟺 accumulation of fullerene carbon cage, so the new alkylated fullerene derivatives are synthesized. The study of self-assembly and optoelectronic performance is a new subject. In this paper, the effects of the structure of alkylated fullerene derivatives, the concentration of solution and the kinds of solvents on the synthesis of controllable morphologies and optoelectronic properties were investigated. Firstly, four alkylated fullerene derivatives with different structures were designed and synthesized. The molecular structure was determined by mass spectrometry (MS),) nuclear magnetic hydrogen spectroscopy (1HNMR). The purified samples were used as self-assembly experiments, including the effects of different concentrations of derivatives and different solvent systems on the self-assembly of alkylated fullerene derivatives. Scanning electron microscopy (SEM) analysis showed that the position of alkyl chain on fullerenes affected the self-assembly of alkylated fullerenes. It is difficult to obtain regular morphology of alkylated fullerene derivative C60-m-hexyl where alkyl chain is in the meta position, while C60-p-hexyl with alkyl chain in opposite position is easy to self-assemble to form regular microstructure. At the same time, compared with C60, the morphology of alkylated fullerenes was formed on the basis of lamellar structure, while bare C60 molecules were easily self-assembled to form regular structure. In the effect of solvent on self-assembly, alkylated fullerene derivatives are easy to form flower or globular structure in the good solvent CCl4 system, and the carbon chain length of the corresponding bad solvent can affect the size of the formation morphology. SEM results show that the morphology and size decrease with the increase of poor solvent carbon chain in CCl4 system. In the experiment of co-assembly of C60-p-hexyl and C60, the morphology and structure are different from the self-assembly. In order to explore the photoelectric properties of alkylated fullerenes, the UV-Vis absorption spectra show that the four alkylated fullerenes have stronger light absorption ability than C60. Electrochemical tests show that alkylated fullerene derivatives have good redox reversibility. Finally, the four derivatives of C60-m-hexyl-C60-p-octylln C60-p-hexylph were applied to organic solar cells. The photovoltaic conversion properties of organic solar cells with C60-m-hexyl as the acceptor material were observed.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O621.13;TM914.4

【参考文献】