新穎窄能隙共軛高分子、染料、及其超分子作用力在有機太陽能電池之合成與應用

Abstract

本篇研究的主要目的是將能帶匯集至一起的窄帶隙共軛聚合物、染料及超分子自組裝與兩個染料和聚合物的有機太陽能電池的應用。在第一章中，簡單介紹對於不同類型的太陽能電池的進化歷史，並比較文獻中不同結構的共軛體系，可應用之高效有機太陽能電池。

在第二章兩個系列的新型對稱受捐助者，受有機感光劑供應量（M1 - M3和M4 - M6的）含有3,6 - 和2,7 -官能咔唑（供體）的核心，分別連接兩個錨固 cyanoacrylic酸（受體）的總量通過不同的號碼（2或3）噻吩共軛連接器（W或W / O型己基側鏈），設計並合成。中間的作用分子平面來源於中央電子基3,6 - 和2,7 -官能咔核心對器件性能進行了研究。一個基於結構的密度泛函理論（DFT）計算確認了效率的染料是關係到核共面的咔唑與噻吩方面的聯繫單位。分子軌道分析反映的合成特點咔唑為基礎的最高佔據分子軌道（HOMOs）和酸分子的最低空軌道（LUMOs）隨著橋噻吩單位必須通過強有力的連接捐助-受體組，而時間密度泛函理論（含時密度泛函理論）計算允許轉讓的HOMO - LUMO的躍遷（>90％）的低能量帶的這些新系統。其中染料、染料敏化的最佳太陽能電池（DSSC電池）的表現獲得了DSSC的裝置，包含電子供應量M1，軸承 3,6 -咔唑官能中心相連的兩個對稱的噻吩組，整體的功率轉換效率（讯）價值 4.82 ％，開路電壓（Voc）為 0.61伏，短路電流密度（Jsc）的對 12.66 mA/cm2時，和填充因子（FF），根據標準的調幅為 0.62，最高1.5陽光入射光當前轉換效率（光電轉換量子效率）的68％。此外，這是非常令人印象深刻的觀察光電轉換量子效率和短路電流值的DSSCs在TiO2基薄膜（3微米），其中包含電子供應量M1和M5均高於染料的DSSC的含釕基N719增敏劑。

在第三章四種新型對稱的有機染料（中一至中四）配置與受體捐助-受體（ADA）的結構中的電子基芴（S1和S2）和N -烷基dithieno [3,2 - B的：2'，3 '維]吡咯（排版）（S3和S4）內核終止了與兩個錨固 cyanoacrylic酸（如電子受體）的合成和應用在染料敏化太陽能電池（DSSCs）。 DSSC的設備的基礎上S2的染料具有最好的光電性能在中一至中四染料：最高單色入射光子對電流的轉換效率（光電轉換量子效率）的76％，短路電流（Jsc）的12.27 mA/cm2時，開路電壓（Voc）為 0.61伏，填充因子（FF）為 0.63，而整體電源轉換效率（η）的4.73％。此外利用chenodoxycholic酸（鵝去氧膽酸）作為共同吸附在納米晶太陽能電池設備的基礎上S3的染料有顯著改善，其η值（從 3.70％至4.31％），這是由於聚集在染料二氧化鈦表面，從而提其應用上的最終價值。

第四章N的一系列新型低帶隙三苯胺為基礎的共軛聚合物（PCAZCN，PPTZCN和PDTPCN）由不同富電子供體主鏈（N -烷基- 2 ,7 -咔唑，噻嗪和cyclopentadithinopyrol，分別）以及氰基和二氰基乙烯電子受體吊墜合成和開發的聚合物太陽能電池（PSC）的申請。對聚合物覆蓋廣泛吸收光譜 400-800 nm的窄的光帶隙範圍 1.66-1.72 eV之間。最高佔據分子軌道（HOMO）和最低未佔據分子軌道（LUMO）水平測定的聚合物循環 voltommetry（簡歷）被發現在該範圍 -5.12至- 5.32V和-3.45至-3.55 eV之間。在100 mW/cm2的調幅 1.5白光照明，體異質結（BHJ）光電器件，包括一個活躍的電子供體層聚合物（PCAZCN，PPTZCN和PDTPCN）混合與電子受體 [6,6] -苯基C61丁酸甲基酯（PC61BM）或[6,6]苯基C71丁酸甲基酯（PC71BM）在不同重量比進行了研究。光伏裝置，包含捐助PCAZCN和受體在1:2的重量比PC71BM具有最高的功率轉換效率（四氯乙烯）的1.28％，與開路電壓為 0.81伏，短路電流 = 4.93 mA/cm2時，和FF = 32.1％。 在第五章的一系列新的氫鍵（H型結構）交聯聚合物絡合生成各種質子供體（H型供體）太陽能電池染料含有3,6 - 和2,7 -官能電子基咔唑核軸承對稱噻吩酸連接器以及cyanoacrylic總站與質子受體（H型受體）側鏈均聚物進行吡啶吊墜（1 / 2的摩爾比為 H-donor/H-acceptor）。超分子的H -鍵結構與 H捐助染料和H -受體側鏈聚合物證實了紅外測量。該超分子結構影響的光，電化學，有機光伏（OPV），達到性能進行了研究。從密度泛函理論（密度泛函理論）計算，優化的幾何結構的有機染料反映，咔唑核的H -捐助染料的共軛平面噻吩和cyanoacrylic酸，這是必不可少的強烈連接整個捐助者在D1受體的單位， D4的染料。在100 mW/cm2的調幅 1.5白光照明，bulkheterojunction（BHJ）電池設備口服脊髓灰質炎疫苗含有活性層的H -鍵聚合物（PDFTP/D1-D4）混合作為電子供體與 [6,6]苯基C61丁酸甲基酯（與 PCBM）作為電子受體在重量比為 1:1進行了探討。從初步調查，口服脊髓灰質炎疫苗裝置，包含重量比為 1:1的H -保稅聚合物與 PCBM顯示 PDFTP/D2和最佳的功率轉換效率（PCE）的價值為 0.31％，而短路電流（Jsc）為 1.9毫安/平方厘米，開路電壓（Voc）為 0.55 V和填充因子（FF）的29％，具有較高的四氯乙烯值比相應的H - D2的捐助染料（四氯乙烯= 0.15％）或H -受體 PDFTP均聚物（四氯乙烯= 0.02％）與 PCBM混合的重量比在1:1。

The prime aim of this review is to bring together the areas of narrow band-gap conjugated polymers, dyes, and the supramolecular self assemblies of both dyes and polymers for the applications of organic solar cells. In the first chapter, a brief introduction of evolution of different types of solar cells has been given and also surveyed the literatures for the different structures of conjugated systems which can be efficient for the applications of organic solar cells. In the Second chapter two series of novel symmetrical acceptor-donor-acceptor organic sensitizers (M1-M3 and M4-M6) containing 3,6- and 2,7-functionalized carbazole (donor) cores, respectively, connected with two anchoring cyanoacrylic acid (acceptor) termini via different numbers (2 or 3) of conjugated thienyl linkers (w or w/o hexyl side-chains), were designed and synthesized. The effects of the molecular planarity originated from the central electron-donating 3,6- and 2,7-functionalized carbazole cores on device performance were studied. A structure-based density functional theory (DFT) calculation confirmed the efficiencies of the dyes being related to the coplanarity of the carbazole cores with respect to the linked thiophene units. Molecular orbital analyses reflected the characterstics of the carbazole-based highest occupied molecular orbitals (HOMOs) and acid-based lowest unoccupied molecular orbitals (LUMOs) along with the bridged thiophene units were essential for strong conjugations across the donor-acceptor groups, while time-dependent density functional theory (TDDFT) calculations allowed the assignment of HOMO–LUMO transitions (>90%) of the low energy bands in these new systems. Among these dyes, the best dye sensitized solar cell (DSSC) performance was obtained from the DSSC device containing M1, bearing 3,6-functionalized carbazole center linked by two symmetrical bithiophene groups, with an overall power conversion efficiency (讯) value of 4.82%, an open circuit voltage (Voc) of 0.61 V, a short circuit photocurrent density (Jsc) of 12.66 mA/cm2, and a fill factor (FF) of 0.62 under standard AM 1.5 sunlight with a maximum incident photon to current conversion efficiency (IPCE) of 68%. Furthermore, it is very impressive to observe the IPCE and Jsc values of the DSSCs in TiO2-based thin films (3 μm) containing M1 and M5 dyes were higher than those of the DSSC containing ruthenium-based N719 sensitizer. In the third chapter four novel symmetrical organic dyes (S1-S4) configured with acceptor-donor-acceptor (A-D-A) structures containing electron donating fluorene (S1 and S2) and N-alkyl dithieno[3,2-b:2',3'-d]pyrrole (DTP) (S3 and S4) cores terminated with two anchoring cyanoacrylic acids (as electron-acceptors) were synthesized and applied to dye-sensitized solar cells (DSSCs). The DSSC device based on S2 dye showed the best photovoltaic performance among S1-S4 dyes: a maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 76%, a short circuit current (Jsc) of 12.27 mA/cm2, an open circuit voltage (Voc) of 0.61 V, a fill factor (FF) of 0.63, and an overall power conversion efficiency (η) of 4.73%. Besides, the utilization of chenodoxycholic acid (CDCA) as a co-adsorbent in the DSSC device based on S3 dye showed a significant improvement in its η value (from 3.70% to 4.31%), which is attributed to the suppression of dye aggregation on TiO2 surface and thus to increase the Jsc value eventually. In the fourth chapter a series of novel low-bandgap triphenylamine-based conjugated polymers (PCAZCN, PPTZCN, and PDTPCN) consisting of different electron-rich donor main chains (N-alkyl-2,7-carbazole, phenothiazine, and cyclopentadithinopyrol, respectively) as well as cyano- and dicyano-vinyl electron-acceptor pendants were synthesized and developed for polymer solar cell (PSC) applications. The polymers covered broad absorption spectra of 400-800 nm with narrow optical bandgaps ranging 1.66-1.72 eV. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels of the polymers measured by cyclic voltommetry (CV) were found in the range of -5.12 to -5.32V and -3.45 to -3.55 eV, respectively. Under 100 mW/cm2 of AM 1.5 white-light illumination, bulk heterojunction (BHJ) photovoltaic devices comprising of an active layer of electron donor polymers (PCAZCN, PPTZCN, and PDTPCN) blended with electron-acceptor [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) or [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) in different weight ratios were investigated. The photovoltaic device containing donor PCAZCN and acceptor PC71BM in 1:2 weight ratio showed the highest power conversion efficiency (PCE) of 1.28 %, with Voc = 0.81 V, Jsc = 4.93 mA/cm2, and FF = 32.1%. In the fifth chapter a series of novel hydrogen-bonded (H-bonded) cross-linking polymers were generated by complexing various proton-donor (H-donor) solar cell dyes containing 3,6- and 2,7-functionalized electron-donating carbazole cores bearing symmetrical thiophene linkers and cyanoacrylic acid termini with a proton-acceptor (H-acceptor) side-chain homopolymer carrying pyridyl pendants (with 1/2 molar ratio of H-donor/H-acceptor). The supramolecular H-bonded structures between H-donor dyes and the H-acceptor side-chain polymer were confirmed by FTIR measurements. The effects of the supramolecular architecture on optical, electrochemical, and organic photovoltaic (OPV) properties were investigated. From DFT (density functional theory) calculations, the optimized geometries of organic dyes reflected that the carbazole cores of H-donor dyes were coplanar with the conjugated thiophenes and cyanoacrylic acids, which is essential for strong conjugations across the donor-acceptor units in D1-D4 dyes. Under 100 mW/cm2 of AM 1.5 white-light illumination, bulkheterojunction (BHJ) OPV cell devices containing an active layer of H-bonded polymers (PDFTP/D1-D4) as an electron donor blended with [6,6]-phenyl C61 butyric acid methyl ester (PCBM) as an electron acceptor in a weight ratio of 1:1 were explored. From the preliminary investigations, the OPV device containing 1:1 weight ratio of H-bonded polymer PDFTP/D2 and PCBM showed the best power conversion efficiency (PCE) value of 0.31% with a short-circuit current (Jsc) of 1.9 mA/cm2, an open-circuit voltage (Voc) of 0.55 V, and a fill factor (FF) of 29%, which has a higher PCE value than the corresponding H-donor D2 dye (PCE = 0.15%) or H-acceptor PDFTP homopolymer (PCE = 0.02%) blended with PCBM in 1:1 weight ratio.