自组装嵌段共轭聚合物电解质及超支化小分子阴极界面修饰应用于聚合物太阳电池

发布时间：2018-01-11 20:38

本文关键词：自组装嵌段共轭聚合物电解质及超支化小分子阴极界面修饰应用于聚合物太阳电池　出处：《南昌大学》2017年博士论文　论文类型：学位论文

【摘要】：体相异质结聚合物(BHJ)太阳能电池(PSCs)因其具有质轻、柔韧性好、便于大面积卷对卷印刷等优点引起了越来越多的关注。近年来,聚合物太阳能电池取得了较大的进步,能量转换效率(PCE)已超过13%。然而,聚合物太阳能电池要实现商业化大面积制备还需要解决一些科学问题,如电荷的分离、传输和收集效率低等限制了其大面积商业化生产。良好的界面接触和优异的界面层和活性层形貌非常重要。因此,需要设计一种能同时调控界面势垒和提高活性层形貌的界面层。共轭聚合物电解质(CPEs)由离域的π共轭主链和功能化的极性侧链组成。由于CPEs和活性层的正交溶解性可避免与憎水性的活性层互混。同时,由于CPEs和金属电极之间存在静电相互作用,可在界面形成偶极子,降低阴极的功函(WF),有利于电荷提取和收集,从而提高器件的PCE。嵌段共轭聚合物因其两端主链之间的不相容性和结晶性差异,嵌段共轭聚合物可自发自组装成有序的纳米结构。如果将嵌段共轭聚合物和CPEs的在分子水平上结合,得到嵌段共轭聚合物电解质(DBCPEs),它将具有许多新颖的性质,如能形成有序的纳米结构、可降低金属电极WF、降低界面势垒和实现环境友好水/醇溶性加工等等。首先,设计合成了两种新型的DBCPEs,分别以芴和噻吩(PFEO-b-PTNBr)以及芴和咔唑(PFEO-b-PCNBr)为主链,功能化极性基团乙氧基链和季铵盐为侧链。将DBCPEs修饰ZnO不仅能够很好地调控ZnO的功函,还能提高无机ZnO和有机活性层之间的界面相容性。此外,自组装的DBCPEs PFEO-b-PCNBr和PFEO-b-PTNBr还能作为模板进一步诱导上层活性层形成有序的纳米纤维和纳米柱状结构,促进电荷的提取和传输。ZnO/DBCPEs双层电子传输层可同时提高器件的各项参数,包含开路电压(Voc),短路电流(Jsc),填充因子(FF)和PCE。最终,以聚(3-己基噻吩)(P3HT):(6,6)-苯基-C61丁酸甲酯(PC61BM)活性层,以ZnO为电子传输层的器件效率为3.0%,以ZnO/PFEO-b-PCNBr为电子传输层的器件效率提升至3.6%。由于ZnO/PFEO-b-PTNBr能形成更大的偶极子和更好的形貌表现出更优越的性能,器件效率提高至3.8%。此外,将ZnO/PFEO-b-PTNBr作为电子传输层,以PBDB-T:ITIC为活性层的器件效率高达10.8%。接着,把性能更好的PFEO-b-PTNBr的结构进一步优化,将侧链的季铵盐阳离子替换成体积更大的咪唑盐阳离子,得到新的DBCPEs PFEO-b-PTImBr。将两种PFEO-b-PTNBr和PFEO-b-PTImBr作为电子传输层应用于聚合物太阳能电池来研究不同末端阳离子对ITO的功函和上层活性层的形貌和排列的影响。自发自组装的PFEO-b-PTNBr和PFEO-b-PTImBr ETLs不仅能在ITO电极和活性层界面产生欧姆接触,还能自组装成蜈蚣状模板进一步诱导活性层形成有利的face-on排列。通过电子顺磁共振(EPR)测试,在两种p-型主链的DBCPEs中均可观察到n-型自掺杂现象,并且PFEO-b-PTImBr比PFEO-b-PTNBr的EPR信号更强。最终,以P3HT:PC61BM为活性层,基于PFEO-b-PTNBr为ETL的器件效率升至3.1%,而基于PFEO-b-PTImBr的效率为3.5%。以PTB7-Th:PC71BM为活性层时,以ZnO/PFEO-b-PTNBr和ZnO/PFEO-b-PTImBr为电子传输层的器件效率分别为9.0%和9.4%。基于ZnO/PFEO-b-PTNBr和ZnO/PFEO-b-PTImBr电子传输层,以PTB7-Th:PC71BM为活性层的器件效率优于传统的已报道的经典的PFN(8.4%)和PFNBr(8.4%)ETLs器件。小分子电解质(SMEs)具有重复性好、易提纯和结构固定等优点。通过一步法简单反应,我们首次报道了一种新型超支化小分子电解质PNSO_3Na,并将其作为电子传输层应用于聚合物太阳能电池。由于一摩尔的PNSO_3Na含有七摩尔的丁基磺酸钠,超支化PNSO_3Na有机界面层能提高界面接触并能调节界面能级,提高器件效率。以P3HT:PC61BM为活性层,相对于ITO器件,以PNSO_3Na为ETL的器件效率从0.8%提高到3.7%。当将ZnO/PNSO_3Na作为电子传输层时,以PBDB-T:ITIC为活性层的器件效率高达11.2%。集合超支化小分子电解质(SMEs)和高电子亲和势材料的双重优势,我们首次设计合成了两种分别以四亚乙基五胺(PDIPN)和丁基磺酸钠四亚乙基五胺(PDIPNSO_3Na)为支链的新型的傒酰亚胺衍生物作为电子传输层。由于极性支链的存在,两种傒酰亚胺衍生物PDIPN和PDIPNSO_3Na ETLs均能形成界面偶极,提高界面接触。因为傒酰亚胺本身具有的高电子亲和势,PDIPN和PDIPNSO_3Na均有来自于极化子的EPR信号峰,表明具有n-型自掺杂效应。此外,相对于PDIPNSO_3Na,PDIPN具有更强的EPR强度,主要归功于PDIPN中四亚乙基五胺支链具有更高的负电荷密度。因此,相对于PDIPNSO_3Na,基于PDIPN ETL展现出更优异的光伏性能。综上表明,这些水/醇溶性DBCPEs和超支化小分子ETLs不仅能改善阴极和活性层之间的界面接触,还能改善活性层形貌,这有利于优化PSCs器件效率并能为可印刷大面积PSCs的制备提供宝贵的参考价值。
[Abstract]:Bulk heterojunction polymer solar cell (BHJ) (PSCs) because of its light weight, good flexibility, easy large-area roll to roll printing has attracted more and more attention. In recent years, polymer solar cells have made great progress, the energy conversion efficiency (PCE) has more than 13%. however, polymer solar cells to achieve commercial production of large area still need to solve some scientific problems, such as charge separation, the large scale commercial production limit transmission and collection efficiency is low. Good interface contact and excellent interface layer and active layer morphology is very important. Therefore, we need to design a kind of can also control the interface barrier and improve the interface active layer morphology. Conjugated polymer electrolyte (CPEs) consisting of polar conjugated backbone and side chain from the functional domain. Since the orthogonal solubility of CPEs and the active layer can be avoided and the hydrophobicity of living Of the mixed layer. At the same time, due to the electrostatic interaction between CPEs and metal electrode can be formed at the interface dipole, decrease the cathode work function (WF), which is beneficial to the charge extraction and collection, so as to improve the device PCE. block copolymer between both ends of the main chain is compatibility and crystallization of difference. Block copolymer can self-assembly into ordered nanostructures. If the block conjugate polymer and CPEs binding at the molecular level, block copolymer of conjugated polymer electrolyte (DBCPEs), it will have many novel properties, such as to form nano ordered structure, can reduce the metal electrode WF, reduce the interface the barrier and environmental friendly water / alcohol soluble processing and so on. First of all, two new types of DBCPEs were designed and synthesized, respectively with fluorene and thiophene (PFEO-b-PTNBr) and fluorene and carbazole (PFEO-b-PCNBr) as the main chain and function of polar groups Oxyethylation Chain and quaternary ammonium salt as side chain. The DBCPEs ZnO is not only able to regulate ZnO function, but also improve the inorganic organic active layer ZnO and the interface compatibility. In addition, the self-assembly of DBCPEs PFEO-b-PCNBr and PFEO-b-PTNBr can be used as a template to induce the upper active layer to form ordered nano fibers and nano columnar the structure, promote the charge extraction and transmission of.ZnO/DBCPEs double electron transport layer can also improve the parameters of the device, including open circuit voltage, short circuit current (Voc) (Jsc), fill factor (FF) and PCE., poly (3- has thiophene (P3HT): (6,6) - phenyl methyl butyrate (-C61) PC61BM) active layer, using ZnO as electron transport layer, device efficiency is 3%, with ZnO/PFEO-b-PCNBr as the electron transport layer to enhance the efficiency of the device 3.6%. due to the morphology of ZnO/PFEO-b-PTNBr can form a larger dipole and better superior. Can improve the efficiency of the device, in addition to 3.8%., ZnO/PFEO-b-PTNBr as electron transport layer, using PBDB-T:ITIC as the active layer of the device efficiency is as high as 10.8%. then, to further optimize the structure of the better performance of PFEO-b-PTNBr, the side chain quaternary ammonium cation substitution into larger imidazolium cations, a new DBCPEs PFEO-b-PTImBr. two PFEO-b-PTNBr and PFEO-b-PTImBr as the influence of morphology and arrangement of electron transport layer used in polymer solar cells to study different cationic ions on ITO at the end of the work function and the upper active layer. The self-assembly of PFEO-b-PTNBr and PFEO-b-PTImBr ETLs can not only produce ohmic contact on ITO electrode and the active layer interface, can self assemble into shape template to induce the centipede the active layer is conducive to the formation of the face-on array. By electron paramagnetic resonance (EPR) test in two types of p- DBCPEs in main chain Observed the self doping phenomenon of type n-, PFEO-b-PTImBr and EPR PFEO-b-PTNBr. The signal is stronger than the final, with P3HT:PC61BM as the active layer, based on the PFEO-b-PTNBr ETL device efficiency rose to 3.1%, while the efficiency of PFEO-b-PTImBr based on 3.5%. with PTB7-Th:PC71BM as the active layer, using ZnO/PFEO-b-PTNBr and ZnO/PFEO-b-PTImBr as electron transport layer, device efficiency was 9% based on 9.4%. and ZnO/PFEO-b-PTNBr and ZnO/PFEO-b-PTImBr with PTB7-Th:PC71BM as electron transport layer, an active layer of the device is more efficient than the traditional reported classic PFN (8.4%) and PFNBr (8.4%) ETLs devices. Small molecule electrolyte (SMEs) has good repeatability, easy purification and fixed structure etc. through one-step simple reaction, we we first reported a novel hyperbranched small molecule electrolyte PNSO_3Na, and its application as an electron transport layer in polymer solar cells. In a molar PNSO_3Na containing seven mol butyl sulfonate, PNSO_3Na hyperbranched organic interface layer can improve the interface contact and can adjust the interface level, improve the efficiency of the device. With P3HT:PC61BM as the active layer, relative to the ITO device, PNSO_3Na ETL device efficiency increased from 0.8% to 3.7%. when ZnO/PNSO_3Na as electron transport layer. With PBDB-T:ITIC as the active layer of the device efficiency is as high as 11.2%. collection of hyperbranched small molecule electrolyte (SMEs) and high electron affinity material advantages, we first designed and synthesized two four ethylene five amine (PDIPN) and butyl sulfonate four ethylene five amine (PDIPNSO_3Na) as Xi imide derivatives the new branch as an electron transport layer. Due to the polarity of branched, two Xi imide derivatives PDIPN and PDIPNSO_3Na ETLs can improve the interface contact interface dipole formation, because Xi imide. High electron affinity amine itself with the EPR signal peak of PDIPN and PDIPNSO_3Na were from that of polarons, with n- type self doping effects. In addition, compared with PDIPNSO_3Na, EPR PDIPN has stronger strength, mainly due to four ethylene amines five branched PDIPN with negative charge density higher. Therefore, compared with PDIPNSO_3Na PDIPN, ETL showed more excellent photovoltaic properties. Based on summing up that the water / alcohol soluble hyperbranched molecules DBCPEs and ETLs not only can improve the interface contact between the cathode and the active layer can improve the morphology of active layer, which is conducive to the optimization of PSCs device efficiency and for the preparation of large area PSCs printing to provide a valuable reference value.

【学位授予单位】：南昌大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O631;TM914.4

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