| 摘要: | 本研究主要合成三個新的含雙吡啶或二氮雜啡衍生物配位基之 釕(Ruthenium)金屬錯合物:CYC-P1、CYC-P2 以及CYC-B1，並探討 其物理性質及在染料敏化太陽能電池(Dye-Sensitized Solar Cells, DSSCs)中作為光敏劑(Photosensitizers)的應用。三個錯合物皆採用 One-pot 的合成方法合成，並利用NMR、IR 與Mass 光譜鑑定其結構， 亦利用理論計算(Semi-empirical ZINDO/1)得知錯合物之HOMOs 與 LUMOs 的定域性(Localization)，以剖析Frontier orbitals 的位置與錯 合物吸光性質之關連性，因CYC-P1、CYC-P2 與CYC-B1 等吸光能 力的差異性主要和其frontier orbitals 的位置(特別是HOMO 部份)有 關。當延長錯合物上ancillary ligand 的共軛長度時，可降低錯合物的 MLCT (metal-to-ligand charge transfer) transition 的能量，但同時也會 降低此吸收峰的吸收係數，這主要是由於錯合物HOMO 的組成有一 部份是來自於ancillary ligand 的貢獻。其中CYC-B1 的吸光係數大於 文獻上所報導所有應用於DSSCs 領域之釕金屬錯合物，因此， CYC-B1 敏化之電池元件具有最高的短路電流密度(23.92 mA/cm2)。 在AM1.5 光源照射下，以CYC-P1、CYC-P2 以及CYC-B1 敏化之 電池元件的光電轉換效率分別為6.01%、3.42 %、與8.54 %。在相同 iv 元件組裝與量測條件下，N3 敏化之電池元件的短路電流密度與光電 轉換效率分別為21.32 mA/cm2與7.7 %。 i Abstract Three new ruthenium complexes (CYC-P1, CYC-P2, and CYC-B1) with the general chemical formula of [Ru(dcbpy)(L)(NCS)2] where dcbpy is 4,4’-dicarboxylic acid-2,2’-bipyridine and L is 3,8-bis-(4-octyl-thiophen- 2-yl)-1,10-phenanthroline, 3,8-bis(4-octyl-5-(4-octyl-thiophen-2- yl)- thiophen-2-yl)-1,10-phenanthroline, or 4,4’-bis- (4’-octyl-bithiophen- 2-yl)-2,2’-bipyridine were prepared and well characterized. The performance of these dye-sensitized solar cells was also explored. These complexes were synthesized via the typical one-pot synthesis and identified with NMR, IR and Mass spectroscopy. In addition, the localizations of HOMOs and LUMOs of these Ru-complexes were calculated with the semi-empirical computation (ZINDO/1) in order to understand the effects of the frontier orbitals on the light harvesting capability of the photosensitizers. It was found that the difference in light harvesting ability between CYC-P1, CYC-P2 and CYC-B1 is associated mainly with the location of the frontier orbitals, especially the HOMO. Increasing the conjugation length of the ancillary ligand decreases the energy of the MLCT (metal-to-ligand charge transfer) transition but at the same time reduces the molar absorption coefficient, due to the HOMO located partially on the ancillary ligand, of the ruthenium complex. The molar absorption coefficient of lower-energy MLCT band of CYC-B1 is very high: higher than all of the reported Ru complexes used in DSSCs. Therefore, the highest short-circuit current density (23.92 mA/cm2) for CYC-B1-sensitized solar cell was achieved. Under the illumination of ii AM1.5 stimulated light, the photon-to-current conversion efficiency of CYC-P1, CYC-P2 and CYC-B1 sensitized cells was 6.01 %, 3.42 % , and 8.54 % respectively. Under the same device fabrication and measuring procedures, the short-circuit current density and conversion efficiency of N3-sensitized cell were 21.32 mA/cm2 and 7.7 % respectively. |
