陳文章臺灣大學:高分子科學與工程學研究所鄭凱方Cheng, Kai-FangKai-FangCheng2010-05-122018-06-292010-05-122018-06-292008U0001-1507200817152600http://ntur.lib.ntu.edu.tw//handle/246246/183103由於分子內電荷轉移的特性，電子施體/受體共軛高分子系統具有調控電子與光電特性的潛力。此博士論文目標在於設計集合成一系列的新型電子施體/受體共軛高分子材料，探討共軛高分子之光電性質與不同的電子施體或受體結構之關係，並近一步製備元件應用於電晶體及發光二極體上。文的第一個部分 (第二章) 為研究電子施體/受體共軛高分子PTHQx於薄膜電晶體的應用。將PTHQx薄膜進行p型態的電晶體測試可以觀察到其電動遷移率為3.6×10-3 cm2V-1s-1，電流開關比高達6×105。原子力顯微鏡顯示了在不同的介質上PTHQx會形成不同的結晶型態而使其FET mobility有極大之改變。此外，高電子遷移速率與雙載子的電荷傳遞特性可以在PTHQx與BBL的混摻系統中被觀察到。電晶體元件在即使含有高達80 wt% PTHQx的不同混摻比例中呈現相當高的並維持一定數值的電子傳遞速率(1.0×10-3 cm2V-1s-1)。 雙載子的電荷傳遞特性則是在PTHQx含量大於90 wt %時被觀察到。混摻系統的原子力顯微鏡影像說明了其相對應的電荷傳遞特性與混摻成分的比例以及相分離的形態有關。文的第二個部分 (第三章) 藉由改變thiophene於共軛高分子中的當量進行一系列PTHTPs電子施體/受體共軛高分子之合成與性質鑑定。實驗中發現當PTHTPs高分子中的thiophene由一個增加至四個時吸收光譜圖的最大吸收峰會由850移至590 nm，而相對應的能隙會由0.97eV增加至1.78eV。這說明了高分子中分子內電荷轉移的程度有所差異。另一方面，若與理論分析的結果相互比較，高分子的能隙也是呈現著隨著高分子中的thiophene當量增加而增加的趨勢。這部分的研究證明了可以藉由改變thiophene於電子施體/受體共軛高分子中的當量對高分子的電子特性進行調控。此外，在這部分的研究中也針對了PTHTP-C7， PTHTP-C12，以及 PBTHTP 進行了電晶體的探討。原子力顯微鏡影像顯示了在PTHTP-C12的長鏈段官能基會使其結構排列成纖維狀的形態而使得PTHTP-C12相對於PTHTP-C7以及 PBTHTP 有著較好的電荷遷移速率。這方面的研究也說明了高分子薄膜電晶體可以藉由形成特殊排列形態進而增加其元件的電荷遷移速率。文的第三個部分 (第四章) 為進行一系列以TH-TQ-TH為主體搭配不同電子施體的電子施體/受體共軛高分子材料之合成與性質鑑定，包括PBTHTTQ，PTTHTQ，PFBTHTQ以及PPTHTQ。在吸收光譜圖的鑑定中我們可以發現最大吸收峰約在710至876 nm之間，而其能隙有著PTTHTQ< PBTHTQ< PFBTHTQ< PPBTHTQ的趨勢，這是因為不同的電子施體與TQ之間分子內電荷轉移作用力的不同進而影響共軛高分子的電子與光電特性。以此TQ系列共軛高分子為材料針對不同沸點的溶劑(氯化苯與氯仿)進行一連串的薄膜電晶體元件量測可以觀察到以氯化苯當溶劑時其元件有較高的遷移率。尤其是以氯化苯當溶劑時，PTTHTQ的電洞遷移率可以高達3.8×10-3 cm2V-1s-1，這可能是因為PTTHTQ具有最低的能隙又或者是因為PTTHTQ在元件中可以形成規則排列而導致的結果。由於TQ系列電子施體/受體共軛高分子具有較廣的吸收峰以及較高的遷移率使得此系列高分子可應用於太陽能元件的開發。文的第四個部分 (第五章) 為合成一新型茀系(fluorene)施體/受體 (PQ)共軛高分子材料(PFPQs)並以此高分子材料為基礎製備高分子混摻系統(BPQ05)使其應用於發光二極體之製備。將此系列高分子與PFQ做比較可以發現與理論分析的結果相似，PFPQ (2.08eV)具有較PFQ (2.64eV)低的能隙，這是因為電子施體與受體之間分子內電荷轉移作用力不同的結果。以此茀系施體/受體系列共軛高分子材料為發光層，藉由精準控制PQ含量的多寡達成不完整的能量轉移可以製備發光顏色為白光之發光二極體。其中，PFPQ0.3與BPQ05發光二極體元件的CIE座標與標準的白光座標(0.33, 0.33)非常接近，分別是(0.34, 0.39)以及(0.31, 0.32)。Abstract..................................................i文摘要.................................................viontents.................................................ixable Captions..........................................xivigure Captions..........................................xvhapter1 Introduction..............................................1-1 Introduction to Conjugated Polymers..............1-1-1 Electronic Structures of Conjugated Polymers.....1-1-2 Tuning of the Electronic Structures of Conjugated Polymers..................................................4-2 Introduction to Donor-Acceptor Conjugated Polymers..................................................7-2-1 Concepts of Donor-Acceptor Conjugated Polymers..................................................7-2-2 Literature Review on Donor-Acceptor Conjugated Polymers.................................................10-2-3 Experimental Research of Donor-Acceptor Conjugated Polymers......................................14-2-3-1 Concepts of Cross- Coupling.....................14-3 Application on Donor-Acceptor Conjugated Polymers.................................................16-3-1 Field-Effect Transistors (FETs) ................16-3-1-1 Introduction to Field-Effect Transistors (FETs) ..................................................16-3-1-2 Donor-Acceptor Conjugated Polymers for Field-Effect Transistors (FETs) ...............................19-3-2 Light Emitting Diodes (LEDs) ...................24-3-2-1 Introduction to Light Emitting Diodes (LEDs) ..................................24-3-2-2 Donor-Acceptor Conjugated Polymers for Light Emitting Diodes (LEDs) ..................................26-3-3 Photovoltaic devices (PVs) .....................32-3-3-1 Introduction to Photovoltaic (PV) ..............32-3-3-2 Donor-Acceptor Conjugated Polymers for Photovoltaic (PV) .......................................35-4 Research Objectives.............................41eferences...............................................44hapter2 Electronic Properties and Field-Effect Transistors of Thiophene-Quinoxaline Donor–Acceptor Conjugated Copolymer................................................49-1 Introduction........................................49-2 Experimental Part...............................51-2-1 Materials.......................................51-2-2 Polymer Synthesis...............................51-2-3 Chemical Structures and Optical Absorption Spectroscopy.............................................52-2-4 Atomic Force Microscopy of Polymer Thin Films...52-2-5 Fabrication and Characterization of Thin Film Transistors..............................................53-2-6 Surface Modification of the SiO2 Dielectric.....53-3 Results and Discussion..........................55-3-1 Optical Absorption Spectra......................55-3-2 Electrochemical Properties......................55-3-3 Thin-Film Transistors...........................56-3-4 Morphology of Polymer Thin Films................59-4 Conclusions.....................................61eferences...............................................62hapter3 Small Band Gap Conjugated Polymers Based on Thiophene-Thienopyrazine Copolymers......................72-1 Introduction....................................72-2 Experimental Part...............................74-2-1 Materials.......................................74-2-2 Synthetic Procedures............................74-2-3 Characterization................................78-2-4 Organic Thin Film Transistor Devices............80-3 Results and Discussion..........................82-3-1 Chemical Structure Characterization.............82-3-2 Thermal properties..............................83-3-3 Optical Properties..............................84-3-4 Electrochemical Properties......................86-3-5 Compare with Experimental Results and Theoretical Analysis.................................................86-3-6 Field Effect Transistor Characteristics.........87-4 Conclusions.....................................91eferences...............................................92hapter4 Synthesis, Properties, and Field Effect Transistor Characteristics of New Thiophene-[1,2,5]thiadiazolo- [3,4-g]quinoxaline-Thiophene based Conjugated Polymers................................................109-1 Intrduction....................................109-2 Experimental Part..............................111-2-1 Materials......................................111-2-2 Synthetic Procedures...........................111-2-3 Characterization...............................116-2-4 Field Effect Transistor (FET) Devices..........118-3 Results and Discussion.........................119-3-1 Polymer Structure Characterization.............119-3-2 Thermal properties.............................120-3-3 Optical Properties.............................121-3-4 Electrochemical Properties.....................122-3-5 Field Effect Transistor Characteristics........123-4 Conclusions....................................126eferences..............................................127hapter5 New Fluorene-acceptor Copolymers: Synthesis, Properties, and Electroluminescence Characteristics.....146-1 Introduction...................................146-2 Experimental Part..............................148-2-1 Materials......................................148-2-2 Polymer Synthesis..............................148-2-3 Preparation of PF-Based Blends.................151-2-4 Characterization...............................151-2-5 Device Fabrication and Testing.................153-3 Results and Discussion.........................155-3-1 Synthesis and Characterization.................155-3-2 Thermal Properties.............................156-3-3 Optical Absorption Properties..................156-3-4 Electrochemical Properties.....................157-3-5 Photoluminescence Properties...................158-3-6 Electroluminescence Properties.................159-4 Conclusions....................................161eferences..............................................162hapter6 Conclusions..................................175ublication Lists.......................................178application/pdf2910126 bytesapplication/pdfen-US電子施體/受體共軛高分子donor-acceptor conjugated polymerthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/183103/1/ntu-97-D92549004-1.pdf