β位烷基取代酞菁作为钙钛矿太阳能电池空穴传输层的应用

β-ALKYL SUBSTITUTED METAL PHTHALOCYANINES AS HOLE TRANSPORT LAYERS IN PEROVSKITE SOLAR CELLS

吴波

11749060

硕士

化学

许宗祥

2019-05-24

2019-07-11

哈尔滨工业大学

深圳

钙钛矿太阳能电池因其制作工艺简单，开路电压理想，器件成本低廉，光电转换效率高等优点备受关注。空穴传输层作为钙钛矿太阳能电池重要组成部分，对提升器件效率以及延长电池寿命起着关键作用。金属酞菁材料具有良好的半导体特性以及热和化学稳定性；合成提纯工艺简单；价格低廉；与钙钛矿材料能级相匹配，是一类理想的空穴传输材料。本研究开发了一系列新型金属酞菁的衍生物，探究此类材料作为钙钛矿太阳能电池的可行性；通过改变中心金属以及延长烷基链，探索不同酞菁分子结构与材料半导体特性的内在联系；构建合适结构的太阳能电池，系统研究材料分子结构对器件性能的影响规律。本研究设计和合成了一系列含有不同中心金属的酞菁衍生物：CuEt2Pc、CuPr2Pc、NiEt2Pc、NiPr2Pc、ZnEt2Pc和ZnPr2Pc，通过质谱、元素分析、红外光谱、紫外可见吸收光谱等技术对材料分子结构进行表征；探索了不同中心金属及乙基取代和丙基取代基团对材料的电子能级，热/化学稳定性，光谱性质的影响规律。电离能测试光电子能谱（IPS）测试结果表明，材料的HOMO能级位于-5.1 eV到-5.2 eV之间，与钙钛矿材料的能级相匹配；使用真空蒸镀法制备酞菁薄膜，掠入式X射线衍射（GIXRD）测试结果，表明烷基链的延长有助于提高薄膜的结晶度，从而提高了薄膜的载流子迁移率（由10-5提升至10-4量级）， 从而更有利于酞菁空穴传输层对活性层光生空穴的提取及传输；原子力显微镜（AFM）测试结果表明，烷基链的延长有助于形成均一、规整薄膜，改善空穴传输层与钙钛矿活性层的界面接触，进而有效降低界面处载流子复合。本研究以上述材料制备空穴传输层，构建结构为FTO/SnO2/ Perovskite/HTL/Au钙钛矿太阳能电池，基于CuEt2Pc、CuPr2Pc、NiEt2Pc、NiPr2Pc、ZnEt2Pc和ZnPr2Pc的器件分别获得9.35%、9.01%、7.97%、12.51%、8.89%和9.87%光电转换效率，其中NiPr2Pc的器件效率最高，测试结果可由良好的载流子迁移率及合适的HOMO能级得到解释。稳定性测试结果表明，新型酞菁空穴传输材料能有效隔绝空气中水氧对钙钛矿活性层的入侵，对钙钛矿层起到良好的封装作用，从而有效提高器件的稳定性及寿命。

Perovskite solar cells have attracted a great deal of attention due to their simple manufacturing process, ideal open circuit voltage, low cost, and high power conversion efficiency (PCE). As an important component of perovskite solar cells, the hole transport layer plays a key role in improving device efficiency and enhancing hole extraction/transport. Metal phthalocyanines (MPcs) with excellent hole transport properties are well known to be both thermally and chemically stable. They can be easily synthesized and purified with low cost, and have suitable energy levels. In this work, a series of novel metal phthalocyanine derivatives were designed and synthesized. The present research is aimed to explore different phthalocyanine molecular structures and material semiconducting properties by changing central metals and extending the substituted alkyl chains. PSCs with the conventional n-i-p structure and based on these materials were fabricated and characterized, and the relationship between the molecular structures of the MPcs and the device performance was systematically studied.In this study, a series of phthalocyanine derivatives containing different central metals were designed and synthesized: CuEt2Pc, CuPr2Pc, NiEt2Pc, NiPr2Pc, ZnEt2Pc and ZnPr2Pc. The molecular structure of the material was studied by mass spectrometry, elemental analysis, infrared and UV-visible absorption spectroscopy. The influences of the different central metals and alkyl substituents on the electronic energy levels, thermal and chemical stability, and spectral properties of the materials was studied. The results of ionization energy test photoelectron spectroscopy (IPS) showed that the HOMO level of the material is located between -5.1 eV and -5.2 eV, which well matched with the energy level of the perovskite material. The thin films of these materials fabricated by thermal evaporation method were studied by grazing incidence X-ray diffraction (GIXRD). The results showed that the elongation of the alkyl chain enhances the crystallinity of the film, and thereby increases the charge carrier mobility of the film (from 10-5 to 10-4 cm2V-1S-1), which can be more favorable for the hole extraction/transport ability of the active layer. The atomic force microscopy (AFM) test results also showed that the elongation of the alkyl chain helps to form a uniform, regular film and improves the interlayer contact between hole transporting and perovskite active layer. So, it can effectively reduce carrier recombination at the interface.In this work, the developed MPc based hole transport layer were employed in perovskite solar cells with the structure of FTO/SnO2/ Perovskite/HTL/Au. The devices based on CuEt2Pc, CuPr2Pc, NiEt2Pc, NiPr2Pc, ZnEt2Pc and ZnPr2Pc were exhibited PCEs of 9.35% and 9.01%. 7.97%, 12.51%, 8.89%, 9.87%, respectively. The highest PCE was achieved for the device based on NiPr2Pc, due to its high carrier mobility and suitable HOMO energy levels. The stability test results confirmed that the newly synthesized MPc based hole transport materials can effectively insulate the intrusion of water and oxygen on the active layer of perovskite, and play a good encapsulation effect on the perovskite layer, and thus effectively improving the stability and life of the device.

钙钛矿太阳能电池 空穴传输材料 非掺杂 金属酞菁 β烷基取代

perovskite solar cells hole transport materials dopant-free metal phthalocyanine β-substituted alkyl group

中文

联合培养

南方科技大学

吴波. β位烷基取代酞菁作为钙钛矿太阳能电池空穴传输层的应用[D]. 深圳. 哈尔滨工业大学,2019.