應用於太陽能電池的梯狀非富勒烯電子接受體與二維高分子的分子設計

在過去二十年有機太陽能電池（OSC）因為成本低、易於加工和有彈性的機械性質因此受到廣泛的關注。然而，材料的結構與其應用在元件上的性能有著很高相關性。高共面性且有良好非定域化π共軛的芳香環結構可以形成強烈的π-π堆疊因而增強電荷輸運，因此被廣泛應用於高性能的有機太陽能電池器件中。在本論文中，我們利用合環得到高平面芳香雜環來設計新穎的小分子電子受體（SMAs）和高分子電子予體。應用於有機光壓電池的新穎共軛小分子受體的合成（第二章）：在本章中，我們詳細說明分子設計理念及合成一種巨大平面的雜環小分子受體DSIC，其兩端有著強拉電子基團INCN。這些拉電子基團可降低LUMO能位使得DSIC構可誘導分子內電荷轉移造成吸收紅移，形成一個窄能隙的小分子電子受體。用於聚合新高分子且具有巨平面芳香雜環側鏈鑲的BDT電子予體單體的合成（第三章）：在本章節中，我們設計並合成苯並[1,2-b：3,4-b'：6,5-b']三噻吩（B3T）位側鏈取代基的新型BDT衍生物單體3B8T，此設計保留特大的π-共軛體系側鏈使對光有額外的吸收，並且增強平面性讓分子堆疊更為容易。除此以外，我們可以預見如果3B8T與共聚合的電子受體基團間沒有能預留分子旋轉或震動的空間，有著大體積的B3T 將會與高分子主鏈上的基團產生空間上的阻礙而造成結構上的扭曲。因此，我們尋找要與之共聚合的電子受體基團時，特別選擇高效能太陽能元件的文獻中，擁有π橋梁能當作空間緩衝的單體基團。將這新型的單體與電子受體單體基團合成新型高分子應用在元件上。

關鍵字

有機太陽能電池；非富勒希小分子電子受體；高分子電子予體

並列摘要

Organic solar cells (OSCs) have received the extended attentions in the last twenty years due to low cost, ease of processing, and mechanical flexibility. Then, the backbone structure of the materials is highly related to the performance of the device. Aromatic fused rings structure with highly planarity and the well-delocalized π-conjugation have been widely applied in the high performance OSCs devices owing to forming the π-π overlaps and enhancing charge transport. In this thesis, we utilized the conception of fused hetero-aromatic on molecular design of the small molecular acceptor (SMAs) and polymer donors respectively. Synthesis of Novel Coplanar Conjugated Small Molecular Acceptors for Organic Photovoltaic cells (chapter 2). In Chapter 2, we show the design and synthesis of a novel small molecule acceptor (DSIC) based on an extended fused core (DBST), end-capped with 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (INCN) groups, and with four 4-hexylphenyl groups substituted on it. Each INCN has one carbonyl and two cyano groups, and these electron-withdrawing groups can downshift LUMO levels. The donor-acceptor structure in DSIC can induce intramolecular charge transfer and red shift absorption to form a narrow energy bandgap molecule. Synthesis of Benzodithiophene (BDT)-Based Conjugated Monomer with Bulky Heteroaromatic Side Chain for Novel Donor Poylmers (chapter 3). In the chapter 3, we designed and synthesized benzo[1,2-b:3,4-b':6,5-b']trithiophene (B3T) substituted benzodithiophene (BDT), namely 3B8T which retains extended π-conjugated system along the side chain for the extra light absorption and even enhance the planarity for better molecular packing. Besides, it can be undoubtedly expected that the torsion will form through the polymer chain if 3B8T is copolymerized with any acceptors without spacer. Therefore, we planned to choose electron-withdrawing acceptors with π-bridges for high optoelectronic performance PSCs.