分子吸收光子的過程是染料敏化太陽能電池(DSCs)工作原理的重要步驟之一。因此設計一個具有良好吸光能力的染料分子是目前DSCs研究的重要目標之一。本篇研究以理論計算的方式探討有機染料分子中，donor、spacer以及acceptor對於分子吸光特性以及電子轉移的影響。本篇研究分為兩部分，第一個部分我們計算四個以donor-cyclopentadithiophene unit-acceptor為基礎結構的分子(W-1~W-4)吸附於(TiO2)38上的UV-vis光譜並分析其電子轉移，討論Spacer及Donor對於短路電流(Jsc)的影響，結合實驗與計算的結果，我們由direct injection的量合理的解釋這四個分子Jsc的差異。第二部分我們計算60個以D-π-A為架構的染料分子，包括5種Donor、4種Spacer以及3種Acceptor，我們也同時考慮Spacer不同的共軛長度對染料分子吸光性質與電子轉移性質的影響，我們的計算結果為不同Donor、Spacer、Acceptor對max，震盪強度，電子轉移量，以及在太陽光下分子吸光後的電子轉移的影響提供了詳細的基準，此外，我們也得到一些規則以合理的設計新型染料分子。 The working principle of dye-sensitized solar cells (DSCs) is light-harvesting processes. Therefore, it is desired to design excellent dyes for high-efficiency light absorbance. However, the effects of the dye on the efficiency (η) of the DSC device are complicated and entangled. This study employs computational methods to investigate the effects of donor, spacer, and acceptor on photo-absorption and electron transfer. In the first part, four donor- cyclopentadithiophene unit-acceptor (D-π-A) organic dyes (W-1~W-4) adsorbed on (TiO2)38 are investigated for the effects of conjugated spacer and donor on the short-circuit current (Jsc) and thereafter the of the corresponding DSCs. We well rationalize the measured Jsc values by the quantity of direct electron injection derived from theoretical calculations and experimental data. In the second part, we investigate 60 “in silico” D-π-A dyes with five types of donor, four types of spacer with various length, and three types of acceptors. We provide a detailed benchmark for the effects of donor, spacer, and acceptor on max, oscillator strength, quantity of electron transfer and quantity of electron transfer under sun light irradiance. Some rules for rational dye design are drawn.
