含噻吩窄带隙共轭聚合物类太阳能电池材料的研究进展

含噻吩的窄带隙共轭聚合物类太阳能电池材料因其良好的稳定性和可加工性,已成为新型太阳能电池的研究热点。本论文主要介绍了用于太阳能电池的窄带隙共轭聚合物研究进展,按其结构特征分为烷基/烷氧基取代聚噻吩、含苯基聚噻吩、基于噻吩并吡嗪的共聚物、基于噻吩并噻唑的共聚物、基于噻吩并吩噻嗪的共聚物、基于烷基芴的共聚物以及其它种类的窄带隙的共轭聚合物,并对它们的结构特点、光学带隙、合成方法进行了归纳与总结。本文最后简要介绍了该研究领域目前所面临的一些问题,同时讨论了该类材料在此领域今后的发展趋势。     

1,4-二酮吡咯并吡咯在聚合物太阳能电池的应用

1,4-二酮吡咯并吡咯(DPP)由于具有优异的共平面性和强烈的拉电子能力,从而被引入D-A型窄带隙共轭聚合物中调控聚合物材料的能隙和能级结构,拓宽在可见光区域的响应范围。近年来,DPP类聚合物太阳能电池材料的研究受到广泛关注,目前基于DPP的聚合物太阳能电池效率高已达9.64%。本文探讨了以DPP作为受体单元而噻吩衍生物、芴、咔唑和苯并二噻吩等作为给体单元制成的D-A型窄带隙共轭聚合物太阳能电池的研究进展,并探讨了聚合物材料结构与太阳能电池性能之间的内在构效关系。     

聚合物太阳能电池材料的研究进展

随着能源短缺和环境污染两大问题日益加重,人们对太阳能开发与利用更加深入。在众多太阳能的利用方式中,太阳能电池被认为是最有前途的。然而无机太阳能电池因其本身缺陷而受到限制。聚合物太阳能电池由于其成本低、质量轻、合成与修饰容易等优点成为太阳能电池研究的热点。近年来,该类太阳能电池的光电转换效率已经超过8%。本文简要介绍了聚合物太阳能电池的基本原理,并从开路电压、短路电流和填充因子等方面着重分析了其材料的设计原则,最后对其未来发展前景作出了展望。     

二噻吩并吡咯-苯并噻二唑D-A型共轭齐聚物的合成、表征及其在体相异质结太阳能电池中的应用

以二噻吩[3,2-b:2',3'-d]并吡咯为电子给体单元、2,1,3-苯并噻二唑为电子受体单元.通过Stille偶联反应合成了4个含不同烷基取代基的给体-受体(D-A)型共轭齐聚物,即O-D3,O-D2P1,O-D1P2和O-P3,它们分别含有3～0个正十二烷基(D=dodecyl)和0～3个支化烷基链戊基己基(P=...     

含萘并二噻吩小分子受体材料的带隙调控及其在非富勒烯太阳能电池中的应用

By using photovoltaic technology, ambient solar light can be directly converted to electricity. The photovoltaic technology has been regarded as one of the most important and promising strategies to resolve the worldwide energy and pollution problems. As one type of photovoltaic technology, polymer solar cells have attracted increasing interest due to their advantages of solution processing capability, low-cost, feasibility to be fabricated on flexible substrates etc. Not until a few years ago, the fullerene derivatives had been dominated the organic photovoltaic field as the most promising acceptor materials for polymer solar cells. However, fullerene-based polymer solar cells have a power conversion efficiency bottleneck due to the relatively fixed energy levels as well as the fixed bandgaps of fullerene derivatives. Therefore, researchers started to develop nonfullerene acceptors which can be used as alternatives to replace the traditional fullerene derivatives. Compared to the fullerene derivatives, nonfullerene acceptors offer several advantages such as stronger light absorption, tunable bandgaps and frontier molecular orbital energy levels. For nonfullerene acceptors, a ladder-type fused ring is usually used as the central core which is an essential building block to tailor the bandgaps and energy levels. Although many fused ring systems have been explored for efficient nonfullerene acceptors, ladder-type angular-shape dithienonaphthalene is seldom reported as the donor unit for nonfullerene acceptors. Furthermore, the impact of thiophene bridge on the optical and photovoltaic properties of the dithienonaphthalene-based nonfullerene acceptors has never been reported. In this context, we report on the design and synthesis of a dithienonaphthalene-based small-molecule acceptor which contains thiophene bridges in between the acceptor terminals and the fused-ring donor core. Compared to the dithienonaphthalene-based small-molecule without the thiophene bridges, the resulting acceptor (DTNIT) exhibits a reduced bandgap of 1.52 eV which makes it more suitable to be blended with the benchmark large bandgap copolymer, poly[(2, 6-(4, 8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1, 2-b: 4, 5-b']dithiophene))-alt-(5, 5-(1', 3'-di-2-thienyl-5', 7'-bis(2-ethylhexyl)benzo[1', 2'-c:4', 5'-c']dithiophene-4, 8-dione)] (PBDB-T). The reduced band-gap of the resulting nonfullerene acceptor can be attributed to its extended π-conjugation in comparison with the dithienonaphthalene-based acceptor without the thiophene bridges. Inverted polymer solar cells with a device configuration of indium tin oxide/ZnO/PBDB-T:DTNIT/MoO₃/Ag were fabricated and characterized. Polymer solar cells based on PBDB-T:DTNIT showed an open circuit voltage of 0.91 V, an enhanced short circuit current of 14.42 mA∙cm⁻², and a moderate PCE of 7.05% which is comparable to the PCE of 7.12% for the inverted device based on PBDB-T:PC₇₁BM. Our results not only provide a method to synthesize efficient nonfullerene acceptors with reduced bandgaps, but also offer a bandgap modulation strategy for nonfullerene acceptors.     

含有呋喃衍生物的窄带隙共轭聚合物的合成及光伏性能研究

通过Stille法将呋喃衍生物苯并二呋喃(BDF)引入共轭主链,合成了苯并二呋喃-呋喃-苯并恶二唑共聚物 (Polymer 1,简称 P1 ).以紫外吸收光谱分析了聚合物溶液及其膜的基本光谱特征,通过理论计算进行了分子模拟,并用电化学循环伏安法测定了其基本的电化学性质.采用此材料为给体,PC71BM为受体制备了本体异质结型的有机太阳能电池器件,同时研究了不同给/受体重量比的情况下以及1,8-二碘辛烷作为添加剂的情况下的光伏器件性能.结果表明, P1 聚合物在可见光区具有较大吸收.由P1所制得的光伏器件,在AM1.5的模拟太阳光照射条件下最高的转化效率为2.96%,表明BDF基团的引入可实现窄带隙的光电聚合物.     

基于二噻吩并吡咯π桥的窄带隙非富勒烯受体材料在有机太阳能电池中的应用

以不同烷基取代的二噻吩并吡咯(DTP)为π桥,连接吲哒省并二噻吩(IDT)中间单元和氰基茚酮(IC)或二氟代氰基茚酮(2F-IC)末端基团,设计并合成了6个窄带隙的非富勒烯受体材料。 其中,IDTDTP-C₂C₂-H和IDTDTP-C₂C₂-F中的DTP单元以1-乙基丙基为侧链,IDTDTP-C₆C₆-H和IDTDTP-C₆C₆-F中的DTP单元以1-己基庚基为侧链,IDTDTP-C₁₂-H和IDTDTP-C₁₂-F中的DTP单元以十二烷基为侧链。 6个分子均具有较窄的光学带隙(1.37~1.44 eV)。 相比于以IC为末端基团的分子(IDTDTP-C₂C₂-H、IDTDTP-C₆C₆-H和IDTDTP-C₁₂-H),由于氟原子的拉电子效应,以2F-IC为末端基团的分子(IDTDTP-C₂C₂-F、IDTDTP-C₆C₆-F和IDTDTP-C₁₂-F)具有红移的吸收光谱,以及更低的最高分子占有轨道能级(HOMO)和最低分子空轨道(LUMO)能级。 以宽带隙聚合物聚[2,6-(4,8-双(5-(2-乙基己基))噻吩-2-基)-苯并[1,2-b:4,5-b']二噻吩-alt-5,5-(1',3'-二-2-噻吩)-5',7'-双(2-乙基己基)-苯并[1',2'-c:4',5'-c']二噻吩-4,8-二酮](PBDB-T)为给体材料,制备了有机太阳能电池器件。 PBDB-T:IDTDTP-C₆C₆-F共混薄膜具有较高且更平衡的空穴/电子迁移率,以及良好的形貌,基于PBDB-T:IDTDTP-C₆C₆-F的有机太阳能电池获得了6.94%的能量转换效率,开路电压为0.86 V,短路电流密度为13.56 mA/cm²,填充因子为59.5%。     

苯并三噻吩共轭聚合物的合成及其在有机光伏中的应用

以三(二亚苄基丙酮)二钯(Pd_2(dba)_3)为催化剂,三甲苯基磷(P(o-tol)_3)为配体,4,3'-十二烷基-2,2'-联二噻吩(M1)和2,8-二溴-5-(2-己基癸基)苯并三噻吩(M2)为单体,采用Stille交叉偶联反应,合成了基于苯并三噻吩和联二噻吩单元的共轭聚合物(PBTT)。采用热重分析、紫外-可见分光光度计及电化学分析分别研究了聚合物PBTT的热性能、光学性能和电化学性能。结果表明:聚合物PBTT具有优异的热稳定性和低的最高占有轨道能级(HOMO);聚合物薄膜最大吸收峰位于469 nm,光学能带隙为2.10 eV;将聚合物与[6,6]-苯基-C_(61)-丁酸甲酯(PC_(61)1BM)共混材料作为活性层制作了本体异质结构太阳能电池器件,在模拟太阳光源AM 1.5 G 100 mW/cm~2照射条件下,该器件获得了高达1.00 V的开路电压,初步的能量转化效率为0.43%。     

含五氟苯的噻吩并吡咯二酮苯并二噻吩共轭聚合物的合成及其性能

以3,4-噻吩二甲酸和五氟苯胺为起始原料,经酰化、缩合和NBS溴代反应制得2,5-二溴-5-五氟苯基噻吩［3,4-c］吡咯-4,6-二酮(2); 2经两步反应制得2-溴-2,5-二噻吩-5-五氟苯基噻吩［3,4-c］吡咯-4,6-二酮(4);以苯并二噻吩衍生物（BDT-1和BDT-2）为给体单元,2或4为受体单元,分别经Stille偶联缩聚反应合成了3个含五氟苯的噻吩并吡咯二酮-苯并二噻吩共轭共聚物(5a~5c),其结构和性能经¹H NMR, ¹³C NMR, UV-Vis, TGA和循环伏安法表征。结果表明：5a, 5b和5c的最大吸收峰分别位于559 nm, 559 nm和547 nm,光学带隙分别为1.70 eV, 1.73 eV, 1.68 eV(薄膜)和1.84 eV, 1.83 eV, 1.81 eV(甲苯);失重5%的温度为307～325 ℃; 5a~5c的起始氧化电位和起始还原电位分别为1.14 V, 1.18 V, 1.03 V和-0.67 V, -0.67 V, -0.70 V; HOMO和LUMO能级分别为-5.54 eV, -5.58 eV, -5.43 eV和-3.73 eV, -3.73 eV, -3.70 eV。     

新型含苯并二噻吩与苯并二吡咯酮基元的D-A共聚物的合成及性质

采用苯并二吡咯酮作电子受体单元,在钯催化下,与不同取代基修饰的电子给体单元苯并二噻吩进行Stille偶联聚合反应,合成了两种新型的电子给-受体(D-A)聚合物(P1和P2),其结构和性能经UV-Vis,~1H NMR,¹³C NMR,元素分析,GPC, CV和TGA表征。结果表明:薄膜态P1和P2在300～800 nm表现出较强吸收。P1和P2的低能端吸收峰值分别位于621 nm和616 nm。氧化峰分别位于0.41 V和0.46 V,能隙分别为1.41 eV和1.36 eV。     

Benzo[1,2-b:4,5-b′]dithiophene-based conjugated polyelectrolyte for the cathode modification of inverted polymer solar cells

A conjugated polyelectrolyte (CPE) named PBNBr, is prepared by post-quaternizing of poly{4,8-bis(octyloxy)benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl-alt-9,9-bis(3′-((N,N-dimethylamino)propyl)fluorene-2,7-diyl} (PBN) with bromoethane. The chemical strucutes, electrooptical properties of the PBNBr is fully characterized. As compared with the PBN, the PBNBr exhibit much better methanol solution processibility, and more effectively tuning ability for the work function (W_f) of ITO (W_F bare ITO, ?4.8 eV, W_F of ITO with PBN interlayer, ?4.1 eV, W_F of ITO with PBNBr interlayer ?3.9 eV). The open circuit voltages (V_OC) and power conversion efficiencies (PCEs) of polymer solar cells from the blend film of poly(3-hexylthiophene) (P3HT) and [6,6]-phenylC₆₁-butyric acid methyl ester (PC₆₁BM) with PBN and/or PBNBr modified ITO as cathode are respectively increased about 27% and 120% in contrast to those for the control devices with bare ITO as cathode. And PCEs of 4.21% and 4.53% are achieved in the PSCs with PBN and/or PBNBr modified ITO as cathode.     

通过F取代调节BDT衍生物给体材料的光伏性能

设计了3个由不同数量的F原子取代的苯并[1,2-b;4,5-b′]二塞吩(BDT)衍生物及其二聚体,采用密度泛函理论研究其电子结构和轨道能级,着重探讨了F原子取代对开路电压的影响.采用含时密度泛函理论模拟了光谱性质,明确了F原子取代对短路电流的影响;同时采用跃迁密度矩阵探讨了它们的激子耦合能力,进而推测F原子取代对光电转换效率的影响,为设计合成新型高效有机太阳能电池给体材料提供了重要的理论依据.     

New 5-Octyl-thieno[3,4-c]pyrrole-4,6-dione Based Polymers: Synthesis and Photovoltaic Properties

Two donor-acceptor conjugated polymers, namely poly{4,8-bis(5-(2-ethylhexyl) thiophen-2-yl)benzo[1,2-b:4,5-b']difuran-alt-5-octyl-4H-thieno[3,4-c]pyrrole-4,6(5H)-dione}(PBDFTTPD) and poly{4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b: 4,5-b']dithiophene-alt-5-octyl-4H-thieno[3,4-c]pyrrole-4,6(5H)-dione}(PBDTTTPD), were synthesized by Stille coupling polymerization reactions. Their structures were verified by ¹H-NMR and elemental analysis, the molecular weights were determined by gel permeation chromatography and the thermal properties were investigated by thermogravimetric analysis. The polymer films exhibited broad absorption bands. The hole mobility of PBDFTTPD:PC₇₁BM(1:2, w/w) blend reached up to 5.5 × 10^?2 cm² v^?1 s^?1 by the space-charge-current method. Preliminary photovoltaic cells based on the device structure of ITO/PEDOT:PSS/PBDFTTPD:PC₇₁BM(1:2, w/w)/Ca/Al showed a power conversion efficiency of 2.32% with an open-circuit voltage of 0.90 V and a short circuit current of 4.40 mA cm^?2.     

基于1,2,4-三氮唑衍生物的共轭聚合物的合成及其光伏性能

以缺电子的1,2,4-三氮唑衍生物作为拉电子结构单元(A), 以富电子的噻吩或苯并二噻吩衍生物作为推电子结构单元(D), 通过Stille偶联聚合的方法, 合成了三种主链型D-A(推-拉电子结构)的交替共聚物PT-TZ, PB-TZ和PB-TTZT. 不同富电子结构单元可使其聚合物表现出不同的光物理性能和光伏性能. 嵌入较多的噻吩单元, 可有效增大聚合物主链的共轭长度, 拓宽其吸收光谱, 因此, 聚合物PB-TTZT的光伏性能明显优于另外两种聚合物. 以三种聚合物分别作为给体材料, 以PC₆₁BM作为受体材料, 制备了聚合物太阳能电池(PSCs), 其中, 基于PB-TTZT的PSCs器件在AM 1.5 G模拟太阳光条件下的光电转换效率为1.18%.     

One pot synthesis of ethyl carboxylate and acetyl selenolo[2,3-b]quinoline derivatives and their tetra/pentacyclic systems

Abstract

Ethylcarboxylate and acetyl selenoloquinoline derivatives were prepared in a one pot synthesis via reaction of sodium hydrogen selenide and 2-chloro-3-cyano-4-methylquinoline followed by reactions with ethyl chloroacetate and chloro acetone respectively which used as precursors to synthesize many of tetra and pentacyclic systems. A new series of pyrimido [4′,5′:4,5]selenolo[2,3-b]quinoline, thiazino[2’,3’:4,5]selenolo[2,3-b]quinoline, oxazino[2',3':4,5]selenolo[3,2-b]quinoline, pyrido[2′,3′:4,5]selenolo[2,3-b]quinoline, pyrido[2′,3′:4,5]selenolo[2,3-b]quinoline-2-substituted selenyl and selenolo[2′,3′:5,6]pyrido[2″,3″:4,5]selenolo[2,3-b]quinoline derivatives were prepared. Elemental analysis, IR, ¹H NMR, ¹³ Abdel-Hafez, S. H.; Gobouri, A. A.; Alshanbari, N. A.; Gad El-Rab, S. M. F. Synthesis of Novel Vitamin E Containing Sulfa Drug Derivatives and Study Their Anti-Bacterial Activity. Med. Chem. Res. 2018, 27, 2341–2352. DOI: 10.1007/s00044-018-2240-7.[Crossref], [Web of Science ®] , [Google Scholar]C NMR and mass spectra confirmed the structures of the newly synthesized compounds.     

D-A Copolymers Based on a Pentacyclic Acceptor Unit and a 3,3′-Difluoro-2,2′-bithiophene for Solar Cells

A D-A copolymer, P2FBTTPTI, was developed by copolymerizing a pentacyclic acceptor unit, thieno[2′,3′:5,6]pyrido[3,4-g]thieno[3,2-c]isoquinoline-5,11(4 H,10 H)-dione(TPTI), with 3,3′-difluoro-2,2′-bithiophene(2 FBT). P2 FBTTPTI possessed a low highest occupied molecular orbital(HOMO) energy level(-5.50 e V) and a good hole mobility(4.14 × 10~(-4) cm~2·V~(-1)·s~(-1)). P2FBTTPTI:PC_(71)BM solar cells gave a decent power conversion efficiency(PCE) of 7.64% and a high open-circuit voltage(V_(oc)) of 0.95 V.