新型无碘准固态电解质的研制及其在染料敏化太阳能电池中的应用

发布时间：2018-01-08 08:33

本文关键词：新型无碘准固态电解质的研制及其在染料敏化太阳能电池中的应用　出处：《武汉大学》2014年博士论文　论文类型：学位论文

【摘要】：二十世纪九十年代诞生的染料敏化太阳能电池(DSSCs)以其成本低廉、性能优越的特点成为硅基光伏器件最具竞争力的替代产品。但传统的含I-/13-氧还电对的有机液态电解质存在易挥发、有毒、吸光、侵蚀金属电流收集极和封装困难等缺陷,影响DSSC的规模化生产和长期稳定性。为此,本论文研发了一些新型不含碘单质(12)的准固态电解质,并探讨了电解质组分对其结晶行为、粘度、离子电导率及由其组装的DSSCs的光电化学性能的影响。获得的主要实验现象和研究结论归纳如下： 1.采用聚氧化乙烯(PEO)为胶凝剂,CuI为p-型空穴传输材料,LiC104为电荷传输助剂制备了CuI凝胶电解质。该电解质中的PEO能有效地抑制CuI的快速结晶,促进TiO2/CuI电解质形成良好的界面接触；而LiC104能将PEO转化为无定形基质以利于电荷传输。在含20wt%PEO的CuI凝胶电解质中掺杂3wt%LiClO4时获得了最高的离子电导率(8.7×10-3S cm-1),且吸附在Ti02表面的Li+能改善电子从激发态染料到Ti02的注入效率,极大地提高了DSSC的效率(2.81%)。与未加PEO(1.46%)或LiClO4(1.30%)的CuI电解质组装的DSSC相比,效率提高了96-116%。这种CuI凝胶电解质具有成本低、操作简便、环保高效等特点,为固态空穴传输材料在DSSC中的应用开辟了新的途径。 2.采用PEO为胶凝剂,离子液体1,2-二甲基-3-丙基咪唑碘(DMPⅡ)为电荷传输介质和碘源制备了离子液体凝胶电解质。由含20wt%PEO的离子液体凝胶电解质组装的DSSC能在不含12的情况下正常工作,并达到4.05%的效率,表明在电解质中去除12以规避其对DSSC困扰的思路是可行的。掺杂5wt%KI可极大地提高电解质的离子电导率(1.63×10-2S cm-1),且K+能抑制PEO的结晶、促进电子在TiO2/染料/电解质界面的迁移,从而将电池的效率提高到5.87%,效率改善了45%。这种离子液体凝胶电解质具有成分简单、操作简便和无毒不泄漏等特点,可为准固态DSSC提供新的高效电解质材料。 3.以1-丁基-3-甲基咪唑碘(BMⅡ)为电荷传输介质和碘源,双三氟甲磺酰亚胺锂(LiTFSI)为电荷传输助剂,采用低粘度的离子液体1-丁基-3-甲基咪唑硫氰酸盐(BMISCN)调节其流变性制备了二元离子液体电解质。由BMⅡ组装的DSSC能在不含12的情况下正常工作但仅获得了2.66%的效率,添加低粘度的BMISCN可降低电解质的粘度并提高电解质中的电荷交换反应,由其组装的DSSC获得了更高效率(4.33%)。LiTFSI不仅能提高电解质的离子电导率,还能改善DSSC中电荷载流子的传输并抑制电荷复合,从而获得了5.55%的效率(与未掺杂相比提高了28%)。这种二元离子液体电解质具有流变性好、无挥发和腐蚀性等特点,为离子液体电解质的研发与应用提供了新思路。 4.为克服离子液体电解质的流动性问题,以丁二腈作为固态溶剂和基质,离子液体BMⅡ和1-丙基-3-甲基咪唑碘(PMⅡ)为电荷传输介质和碘源制备了新型塑晶离子液体电解质。掺杂5wt%LiClO4到塑晶电解质中时,Li+与丁二腈能通过配位作用将结晶性基质转化为无定形含盐基质,改善了电解质的离子电导率,还能通过静电作用力吸引-和形成的13-以促进其电荷交换反应,进而将DSSC的效率提高到5.50%(与未掺杂相比提高了157%)。这种不含12的塑晶离子液体电解质具有机械性能好、便于封装以及无挥发和腐蚀性等特点,在柔性或固态DSSC的规模化生产方面具有较好的应用前景。 5.为验证不含I2的离子液体凝胶电解质在染料共敏化DSSC中应用的可行性,采用分步共敏化方法将光谱响应范围互补的有机染料OD-8与D149或SQ2联合对Ti02光阳极进行共敏化并组装成准固态DSSC,利用OD-8和D149或SQ2的吸收光谱匹配互补的特性提高电池的光捕获效率。OD-8/D149(6.21%)或OD-8/SQ2(6.10%)共敏化DSSC的效率均远高于OD-8(4.53%),D149(5.46%)和SQ2(2.86%)单一染料敏化的DSSC此外,不含I2的离子液体凝胶电解质在共敏化DSSC中能成功发挥电解质的功能,且表现出比传统有机液态电解质组装的共敏化DSSC更高的短路电流、开路电压和电池效率,表明不含I2的离子液体凝胶电解质在共敏化DSSC中具有显著的应用前景,也为替代价格昂贵的钌联毗啶类染料和发展宽光谱响应、高效环保的DSSCs提供了一些新的思路。
[Abstract]:The dye-sensitized solar cell (DSSCs) was born in 1990s with its low cost, superior performance characteristics of silicon based photovoltaic devices become the most competitive alternative products. But the traditional I-/13- oxygen also of organic liquid electrolyte are volatile, toxic, light absorption, corrosion of metal current collector and encapsulation difficulty effect of large-scale production and long-term stability of DSSC. Therefore, this thesis developed some new elemental iodine (12) of the quasi solid electrolyte, and discusses the viscosity of electrolyte component on the crystallization behavior, and effects of photoelectrochemical properties and conductivity of DSSCs by its sub assembly. The main conclusions obtained by experimental phenomena and study are summarized as follows:
1. using poly ethylene oxide (PEO) as gelling agent, CuI p- as hole transport materials, LiC104 prepared CuI gel electrolyte for charge transfer. The electrolyte additives for rapid crystallization of PEO can effectively inhibit CuI and promote TiO2/CuI electrolyte to form a good interface contact; while LiC104 PEO can be transformed into amorphous in order to obtain the charge transfer matrix. The highest ionic conductivity of 3wt%LiClO4 doped in CuI gel electrolyte containing 20wt%PEO in (8.7 * 10-3S cm-1), and can improve the adsorption of electrons from the excited dye to Ti02 injection efficiency on the surface of Ti02 Li+, which greatly improves the efficiency of DSSC (2.81%) and not. PEO (1.46%) or LiClO4 (1.30%) compared to the CuI electrolyte DSSC, to improve the efficiency of the 96-116%. CuI gel electrolyte has the advantages of low cost, simple operation, environmental protection, etc., for the application of solid hole transport material DSSC in the open A new way is made.
2. using PEO as gelling agent, ionic liquid 1,2- two -3- methyl propyl iodide (DMP II) prepared by ionic liquid gel electrolyte for charge transfer medium and source of iodine. Assembled by ionic liquid gel electrolyte containing 20wt%PEO DSSC can work normally in excluding 12 cases, and achieved 4.05% efficiency, that in the electrolyte removal of 12 to avoid the idea of DSSC problem is feasible. The doping of 5wt%KI can greatly improve the ionic conductivity of the electrolyte (1.63 * 10-2S cm-1), K+ and PEO can inhibit the crystallization, promote the electron migration in TiO2/ dye / electrolyte interface, which will improve the efficiency of the battery to 5.87%, improve the efficiency of the 45%. of this ionic liquid gel electrolyte has simple components, easy operation and non-toxic, leakage and other characteristics, can provide efficient new electrolyte for quasi solid state DSSC.
3. to 1- butyl -3- methylimidazolium iodine (BM II) as charge transfer medium and a source of iodine, double three fluorine methyl sulfonyl imide lithium (LiTFSI) charge transfer agent, the low viscosity of ionic liquid 1- butyl -3- methylimidazolium thiocyanate (BMISCN) ionic liquid electrolyte two yuan adjustment of its rheology system the preparation of DSSC assembled by BM. In the case with 12 under normal work but only got 2.66% of the efficiency, add a low viscosity BMISCN can reduce the viscosity of the electrolyte and improve the charge in the electrolyte exchange reaction by the assembly of the DSSC obtained a higher efficiency (4.33%).LiTFSI can not only improve the ionic conductivity of electrolyte the charge carriers can improve the transmission of DSSC and suppress the charge recombination, to obtain a 5.55% efficiency (compared with the undoped increased 28%). This two yuan of ionic liquid electrolyte has good rheology, no volatilization and corrosion resistance, for A new idea for the development and application of ionic liquid electrolytes is provided.
4. to overcome the liquidity problems of ionic liquid electrolytes, with two as the solvent and solid butyl nitrile matrix, ionic liquid BM and 1- II -3- propyl methyl imidazole iodine (PM II) to prepare a new plastic crystal ionic liquid electrolyte for charge transfer medium and source of iodine doped 5wt%LiClO4 system. To the plastic crystal electrolyte at Li+ and two D by coordination function to various crystalline matrix into amorphous salt matrix, improve the ionic conductivity of the electrolyte, but also through the electrostatic force to promote the charge exchange reaction attraction and the formation of 13-, which will improve the efficiency of DSSC to 5.50% (compared with the undoped increased by 157%). This does not contain 12 plastic crystal ionic liquid electrolyte has good mechanical properties, easy package and no volatilization and corrosion resistance and other characteristics, and has good application prospects in large scale production of flexible or solid DSSC.
5. for the feasibility of the application of ionic liquid gel electrolyte without I2 verification in dye sensitized DSSC in the step by step cosensitized methods spectral response range of complementary organic dyes OD-8 and D149 or SQ2 on Ti02 photoanode were sensitized and assembled into a quasi solid state DSSC, complementary characteristics to improve battery efficiency of light capture the.OD-8/D149 absorption spectra of OD-8 and D149 or SQ2 (6.21%) or OD-8/SQ2 (6.10%) of the total efficiency of sensitized DSSC were much higher than that of OD-8 (4.53%), D149 (5.46%) and SQ2 (2.86%) single dye sensitized DSSC in ionic liquid gel electrolyte containing I2 electrolyte can not play in the cosensitization successfully in DSSC, and shows the short-circuit current than the traditional organic liquid electrolyte co sensitization of DSSC high efficiency, open circuit voltage and battery, showed that the ionic liquid gel electrolyte without I2 significantly in CO sensitization in DSSC The application prospect also provides some new ideas to replace the expensive ruthenium dyestuff dyes and to develop the wide spectrum response and the efficient and environmentally friendly DSSCs.

【学位授予单位】：武汉大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：O646;TM914.4

【共引文献】