几种新型光电活性材料的制备及其在染料敏化太阳能电池与分析检测中的应用

发布时间：2018-01-09 01:00

本文关键词：几种新型光电活性材料的制备及其在染料敏化太阳能电池与分析检测中的应用　出处：《中南大学》2014年博士论文　论文类型：学位论文

【摘要】：摘要：光电活性材料包括有机染料及荧光分子、过渡金属复合物、半导体氧化物、量子点(QDs)等。其优良的物理化学性质使其在光电转换、光催化以及分析检测方面具有广泛的应用。染料敏化太阳能电池(DSSCs)制作成本较低、环境友好是一类被广泛关注的新型太阳能电池。目前实验室得到的DSSCs的最高效率为13%,但与传统的硅基太阳能电池的效率(约30%)还有较大差距。在DSSCs中,电解质氧化还原电对电位与氧化态染料分子能级之间的不匹配是造成电池开路电压和总体效率中偏低的主要原因。而TiO2中光电子与氧化态电解质的复合,阻碍了DSSCs中具有较高电势电解质的使用。针对这问题,在本研究中使用硅烷化处理的有序一维TiO2纳米线阵列作为DSSCs的光阳极,这种开放的结构更有利于形成规则的聚硅氧烷修饰层来阻止光电子的复合,从而为DSSCs中使用高电势电解质成为潜在可能。QDs具有独特的光电性质,已被广泛应用于构建无机离子及生物分子传感器。但这些基于QDs的传感器中,大部分需要进行繁琐的表面修饰和功能化处理。借助化学修饰方法研究基于QDs的简易传感器有很重要的意义。比色检测方法具有操作便利、结果直观等特点,得到了广泛的应用。设计合成新型有效的比色法探针也是研究的热点。本论文设计合成了几种新型光电活性物质,并将它们应用于了DSSCs与分析检测中。主要内容包括： (1)用水热法制备了一维有序结构的TiO2纳米线,在吸附染料后通过硅烷化处理得到的光阳极中,光电子与高活性电解质(Fc+/Fc)间的复合被有效地阻止了。红外光谱证实了聚硅氧烷层的形成。TiO2纳米线阵列为表面修饰提供一种更开放和便于操作的结构,X射线散射能谱显示Si在TiO2纳米线为均匀分布状态。电池性能测试结果表明,硅烷化处理后,在Fc+/Fc电解质中,电池的开路电压及效率都显著地提高了,光阳极中电子的寿命也呈指数关系地增长了。该电极的设计为DSSCs中使用与光敏剂能级更加匹配的电解质提供了可能。 (2)引入化学还原方法(还原剂为抗坏血酸,AA),使Cu2+能快速地还原成一价铜并以Cu2S的形式沉积在CdS量子点表面。通过观测CdS量子点在650nm处荧光强度的变化,可在1nM至1μM范围内实现对Cu2+的快速专一检测,检测限为0.5nM,与传统的基于量子点的方法相比低了2至3个数量级。对水样和人脑脊液实际样品中Cu2+含量进行了测试,得到了与标准ICP-MS检测类似的结果,说明该方法有较高的可行性。 (3)通过层层组装的方法得到了CdS量子点固载的光电化学电极,将CdS量子点表面富集S2-后电极能产生将强的光电流响应。而电极用半胱氨酸处理后,由于Cys能取代CdS量子点表面的S2-,使得光电流信号下降。实现了对Cys的灵敏检测,检测线性范围为1-100nM,检测限为0.4nM。该方法成功应用于了血清样品中Cys的检测。 (4)根据Cys和N3染料竞争对Hg2+结合,利用Hg2+-N3复合物实现了对Cys的比色法检测。首先,由于N3染料分子中SCN基团与Hg2十的配位作用,形成得到Hg2+-N3复合物,对应溶液颜色由红色变为黄色。在Cys的存在下,Cys的巯基与Hg2+具有更强的结合作用,从而将Hg2+-N3复合物中的Hg2+置换,N3染料分子被释放,溶液颜色恢复至红色。基于上述原理实现了对Cys的定量检测,其检测范围为0.5-25μM,检测限57nM。在此基础上,通过在配体联吡啶环上引入磷酸基团,得到了全水溶性的含钌染料。利用该染料分子实现了对水溶液体系中Hg2+的检测。 (5)将水杨醛单元与萘酰亚胺重氮盐偶联反应得到了基于萘酰亚胺的偶氮苯染料分子探针1。在探针1中,水杨醛为CN-的识别基团,萘酰亚胺偶氮苯为检测信号基团。与CN-反应后,探针1溶液显示出了从黄到红的显著颜色变化,对应光谱吸收峰位置从408nm移置497nm。在优选的H2O/DMSO (7/3, v/v)混合溶剂体系中,探针1.能实现对CN-的比值式检测,检测范围为2-45μM,检测限为0.4μM。而且该方法具有很高的特异性。另外,利用探针1制备了CN-检测试纸,可目测出浓度大于20μM的CN-溶液。
[Abstract]:Abstract: optical active material includes organic dyes and fluorescent molecules, transition metal complexes, oxide semiconductor, quantum dots (QDs). Its excellent physical and chemical properties in the photoelectric conversion, with wide application of photocatalytic and analysis. The dye-sensitized solar cell (DSSCs) lower production cost. Environment friendly is a new type of solar cell is a widespread concern. At present the highest efficiency obtained in the laboratory of DSSCs is 13%, but the efficiency of silicon solar cells and the traditional (about 30%). There is a large gap in DSSCs, electrolyte redox couple mismatch between the potential and the oxidation state of dye molecule level is the main reason causing the battery open circuit voltage and low overall efficiency. And the photoelectron and electrolyte oxidation state in TiO2 composite, blocked the use of high potential electrolyte DSSCs. Aiming at this problem, in the Use of ordered one-dimensional TiO2 nanowire array silanation as photoanode DSSCs in this study, the composite structure is more open to form a regular polysiloxane modified layer to prevent the photoelectron, so as to use DSSCs in the high potential electrolyte potential.QDs has unique photoelectric properties, has been widely used in the construction of inorganic ions biological and molecular sensor. But these sensors based on QDs, most of the surface modification and function of complex processing. By the study of the chemical modification methods of simple sensor based on QDs has very important significance. With convenient colorimetric detection method, the characteristics of intuitive results, has been widely used. The design and synthesis of new and effective the ratio of hot color probe is also research. Several new photoelectric active substances were designed and synthesized in this paper, and apply them to the DSSCs The main contents of the analysis are as follows:
(1) TiO2 nanowires ordered structure were synthesized by hydrothermal method. The adsorption of the dye by photo anode in the silane treatment, optoelectronics and high activity of electrolyte (Fc+/Fc) between the compound being effectively prevented. The infrared spectra confirmed the formation of.TiO2 nanowire arrays for surface modified polysiloxane layer provides a a more open and convenient operation of the structure, X ray scattering spectra showed that Si in TiO2 nanowires with uniform distribution state. The test results show that the performance of the battery, silylation, in Fc+/Fc electrolyte, the open circuit voltage and efficiency of the battery has significantly increased, the photoanode electron lifetime is exponential relationship growth. Design of the electrode for possible use of electrolyte to match with the level of the photosensitizer DSSCs.
(2) the introduction of chemical reduction method (reducing agent for ascorbic acid, AA), the Cu2+ can quickly restore the copper in the form of Cu2S deposited on the surface of CdS quantum dots by observation of CdS quantum dots in 650nm fluorescence intensity changes, can achieve rapid specific detection of Cu2+ in 1nM to 1 M range, the detection limit is 0.5nM, and the traditional method based on quantum dots is low compared to 2 to 3 orders of magnitude. The content of Cu2+ and cerebrospinal fluid samples in real samples were tested by standard ICP-MS detection and similar results illustrate the feasibility of this method is high.
(3) through the layer by layer assembly method obtained photoelectrochemistry electrode supported CdS quantum dots, CdS quantum dots surface enrichment of S2- electrode can generate a photocurrent response will be strong. With cysteine electrode, because Cys can replace CdS on the surface of quantum dots S2-, the light current signal is realized decreased. Sensitive detection of Cys, the linear range of detection was 1-100nM, the detection limit is 0.4nM. this method is successfully applied to the detection of serum Cys in the sample.
(4) according to Cys and N3 dye competition for binding to Hg2+, implementation of Cys colorimetric assay using Hg2+-N3 complexes. Firstly, because the N3 dye molecules in SCN group and Hg2 ten ligand, forming Hg2+-N3 complex, corresponding to the color of the solution changed from red to yellow in the presence of Cys. Hg2+ and Cys, thiol binding effect, which will replace Hg2+ Hg2+-N3 complexes, N3 dye molecules are released, the color of the solution returned to red. The above principle realizes the quantitative detection of Cys based on the detection range of 0.5-25 M, the detection limit of 57nM. on the basis of this, through the combination of ligand pyridine ring into the phosphate group, the water soluble ruthenium dye. To detect Hg2+ in aqueous solution of the dye molecules.
(5) the salicylaldehyde unit and naphthalimide diazonium salt coupling reaction was obtained based on azo dye molecule probe Naphthlimide 1. probe in 1, salicylaldehyde recognition group CN-, naphthalimide azobenzene groups. As the detection signal and CN- reaction, the probe 1 showed from solution yellow to red color changes significantly, the corresponding spectral absorption peaks in the preferred H2O/DMSO from 408nm 497nm. (7/3, v/v) to displace the mixed solvent system, 1. probe can realize the detection of the CN- ratio, the detection range is 2-45 ~ M, the detection limit is 0.4 M. and the method has high specificity. In addition, the CN- test was made by 1 probe system, can measure the concentration of CN- at more than 20 M.

【学位授予单位】：中南大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TM914.4;O657

【共引文献】