有機太陽能電池被視為低成本及低環境汙染的永續性電力來源。而電洞型有機材料應用於有機太陽能電池中做為電子予體在近年來發展迅速。近來小分子有機太陽能電池的元件表現已逼近高分子有機太陽能電池的成果,顯示其有相當大的潛力取代矽基太陽能電池成為下一世代的光伏電池。本篇研究著重於有機太陽能電池中,具予體-受體-受體(D-A-A)結構的小分子電子予體材料,其設計開發、合成及分子特性的鑑定。此外,藉由探討D-A-A電子予體中各單元體的組成和特性,可得知化學結構、分子性質和元件表現之間的關係。文中將於第一章介紹小分子電子予體材料的設計原理,並將其應用在D-A-A架構的電子予體中。而其他章節將介紹各個功能性單元體於D-A-A電子予體中對於分子特性的影響,包括:推電子基團(D)對小分子的電化學性質和分子立體障礙的影響。利用不對稱合成建構各種D-A-A電子予體的中間拉電子基團(A),並應用在有機太陽能電池中。修改D-A-A電子予體的末端拉電子基團(A)進行分子能階的調控,並透過簡單快速的方法來合成電子予體以實現永續化學的理念。藉由各個單元體在D-A-A電子予體中的排列組合,我們可以控制有機小分子電子予體的各項性質,並且探討及連結分子結構和有機小分子太陽能電池效率表現的關係。
rganic Solar Cells (OSCs) have been regard as cost-effective and promising sources of electricity with environmentally benign sustainability. The p-type organic materials as electron donors for OSCs were developed prosperously in the past few decades. Recently, the performance of small-molecule organic solar cells (SMOSCs), has approached the results that organic polymer solar cells achieved, demonstrated high potential as alternatives to silicon-based solar cells for the next generation of power sources in photovoltaics (PV). The research in this dissertation was focus on the design, synthesis, and characterization of small-molecule materials with donor-acceptor-acceptor (D-A-A) molecular configuration for OSCs. Furthermore, each part of composition in D-A-A donors was investigated to develop the relationship between the structure-property and photovoltaic performance. In this dissertation, design principles for small-molecule materials were illustrated in Chapter 1 and contributed into the construction of D-A-A organic donors. Further discussion of each functional moieties in D-A-A organic donors along with various fundamentality-influence were organized including electronic and steric effects of electro-donating units, the novel asymmetric strategies for diversity of middle electron-withdrawing units in OSCs, the manipulation of energy levels through the modification of terminal electro-withdrawing units and their application in one-step synthesis of D-A-A organic donors for sustainable chemistry. Through the permutation and combination of building block in the D-A-A organic donors, we could control the intrinsic properties of D-A-A organic donors that were explored to connect the molecular structures with the performance of SMOSCs.