【作者】 汪恒；

【导师】 韩宏伟；

【作者基本信息】 华中科技大学 ， 光电信息工程， 2013， 博士

【摘要】 染料敏化纳米晶太阳能电池(DSSC)是20世纪90年代研发出来的一种新概念太阳能电池，由于其主要原材料成本低廉，生产工艺简单，因此受到科研人员和投资者的广泛关注。依据电解质的不同，DSSC主要分为液态DSSC和全固态DSSC。其中液态DSSC存在液态电解质挥发以及泄漏等问题，阻碍了其大规模应用。而全固态DSSC主要采用空穴传输材料替代液态电解质。相对于液态DSSC，全固态DSSC避免了电解质挥发或泄漏等问题。同时，全固态DSSC主要采用的是单基板结构，该结构是将光阳极和对电极集成在单一导电衬底上，从而进一步降低了器件成本。因此单基板全固态DSSC比液态DSSC更具有应用前景。单基板全固态DSSC主要由光阳极、空穴传输材料和对电极组成。单基板全固态DSSC目前存在的主要问题为工艺复杂和效率低。传统的单基板全固态DSSC中工艺最复杂的部分为对电极的制备：高真空条件下于空穴传输材料层上热蒸镀一层金属（Au或Ag）。目前，对于单基板全固态DSSC中对电极的研究很少，有待开发新的对电极材料和工艺。此外，染料、空穴传输材料和光阳极结构也是单基板全固态DSSC中有待改进的方面。基于单基板全固态DSSC中存在的问题，本论文以可印刷的碳材料作为对电极替代了传统的蒸镀金属电极，研究了碳对电极结构对基于聚3-己基噻吩（P3HT）的单基板全固态DSSC性能的影响。同时，对于空穴传输材料P3HT，本文采用近红外吸收的染料SQ2来研究电池的单色光量子效率。对于空穴传输材料spiro-OMeTAD，本文研究了光掺杂对电池性能的影响。此外，本文还研究了光阳极结构对单基板全固态DSSC性能的影响。本论文的主要内容如下：首先，针对单基板全固态DSSC中对电极工艺复杂的问题，以石墨和炭黑复合材料作为对电极并采用简单的丝网印刷法制备了基于P3HT的单基板全固态DSSC。讨论了对电极结构以及绝缘层和光阳极厚度对电池性能的影响。通过优化，在一个标准太阳光（AM1.5100mW cm-2）下获得了3.11%的光电转换效率。其次，针对P3HT与D102染料吸收重叠的问题，采用近红外吸收的方酸染料SQ2作为敏化剂制备了基于P3HT的单基板全固态DSSC，并研究了SQ2的分子结构以及LiTFSI处理对电池性能的影响。通过优化，基于SQ2与P3HT的单基板全固态DSSC获得了2.2%的光电转换效率。再次，采用spiro-OMeTAD作为空穴传输材料制备了基于介孔碳对电极的单基板全固态DSSC。研究了光掺杂程度对器件性能的影响。进一步分析了光掺杂对TiO2/spiro-OMeTAD界面电子复合和spiro-OMeTAD/C界面电子传输的影响。通过优化光掺杂对spiro-OMeTAD的氧化程度，基于spiro-OMeTAD的单基板全固态DSSC获得了4.04%的光电转换效率。最后，针对传统光阳极结构对光的利用率低的问题，采用TiO2介孔球作为光阳极制备了基于spiro-OMeTAD的单基板全固态DSSC并获得了4.0%的光电转换效率。对比了TiCl4处理对于TiO2介孔球光阳极与TiO2纳米颗粒（P25）光阳极的光伏性能的影响。研究了两种光阳极的散射性能以及电子传输性能。更多还原

【Abstract】 Dye-sensitized nanocrystalline solar cell (DSSC) is a new kind of solar cell, whichwas firstly developed in1990s. Because of its low cost materials and simple fabricationprocess, DSSC has attracted great attention from researchers and investors. From itsdifferent electrolytes, DSSC is mainly divided into the liquid DSSC and the solid-stateDSSC. Among them, the liquid DSSC meets many problems such as solvent evaporationand electrolyte leakage, which hinder its large-scale application. In contrast, the solid-stateDSSC mainly apply hole transporting materials to replace the liquid electrolyte. Comparedwith the liquid DSSC, the solid-state DSSC avoid electrolyte evaporation or leakageproblems. Moreover, the solid-state DSSC is mainly created with monolithic structure,where the photoanode and the counter electrode are integrated on a single conductivesubstrate, which further reduces the cost of the device. As a result, the monolithicall-solid-state DSSC has more application prospect than the liquid DSSC.Monolithic all-solid-state DSSC is mainly composed of photoanode, hole transportingmaterials and counter electrode. At present, monolithic all-solid-state DSSC mainly sufferfrom complicated fabrication and low efficiency. The most complicated process intraditional monolithic all-solid-state DSSC is the fabrication of counter electrode:depositing a metal layer (Au or Ag) on the hole transporting matertial under high vacuum.Currently, there are only a few research on the counter electrode of monolithicall-solid-state DSSC. Therefore, the development of new materials and process of counterelectrode is indispensable. In addition, dye, hole transporting materials and photoanodealso need improvement for monolithic all-solid-state DSSC.Herein, based on printable carbon material as counter electrode (CE) instead oftraditional evaporated metal electrode, we investigate the effect of the carbon CE structureon the performance for all-solid-state DSSC based on poly(3-hexylthiophene)(P3HT).Meanwhile, for the hole transporting material P3HT, near-infrar dye SQ2was used tostudy the incident photon to electron conversion efficiency. For the hole transportingmaterial spiro-OMeTAD, the influence of photo-doping on the performance of deviceswas investigated. In addition, the effect of photoanode structure on the performance of monolithic all-solid-state DSSC was studied. The main contents of this thesis are listed asfollowing:Firstly, due to the complicated fabrication of counter electrode for monolithicsolid-state DSSC, graphite and carbon black composite material was used as CE tofabricate P3HT-based monolithic solid-state DSSC by screen printing. The influence ofCE structure and the thickness of insulating layer and photoanode layer on theperformance for devices were studied. After optimization, an efficiency up to3.11%wasachieved for the monolithic solid-state DSSC under a standard solar illumination (AM1.5100mW cm-2).Secondly, due to the absorption competition between P3HT and D102dye, the nearinfrared squarine dye SQ2sensitizer was used to fabricate P3HT-based monolithicsolid-state DSSC, and the effects of molecular structure of SQ2and LiTFSI treatment onthe performance of the devcies were investigated. An efficiency of2.2%was achievedwithin monolithic solid-state DSSC based on SQ2and P3HT.Thirdly, spiro-OMeTAD was used as a hole transporting material to fabricatemonolithic solid-state DSSC based on mesoporous carbon CE. The effect of photo-dopingon the performance of devices was investigated. Moreover, the influences of photo-dopingon the charge recombination at spiro-OMeTAD/C interface and on the charge transfer atTiO2/spiro-OMeTAD interface were analyzed. Through the optimization on the level ofphoto-doping, an efficiency of4.04%was achieved within spiro-OMeTAD basedmonolithic solid-state DSSC with carbon CE.Finally, due to the insufficient light trapping for traditional photoanode, mesoporousTiO2beads was used as photoanode to fabricate monolithic solid-state DSSC based onspiro-OMeTAD and an efficiency of4.0%was achieved. The effect of TiCl4treatment onthe photovoltaic performance for TiO2beads phonoanode and P25nanoparticlesphonoanode were studied. The scattering properties and electron transport properties ofthe two photoanodes were also investigated.更多还原