應用於染料敏化太陽能電池之新型釕金屬錯合物的合成與性質探討

A Novel Ruthenium-Based Photosensitizer for Dye-Sensitized Solar Cells

吳錫章(Shi-Jhang Wu)

指導教授 ： 吳春桂

國立中央大學/理學院/化學系/碩士(2007年)

摘要

本研究主要合成二個新的含雙吡啶配位基之釕金屬錯合物：SJW-E1以及CYC-B3，並探討其物理性質及在染料敏化太陽能電池(Dye-Sensitized Solar Cells, DSCs)中作為光敏劑的應用。兩錯合物最大的差異在於輔助配位基 (ancillary ligand)的不同，其中CYC-B3為alkyl-thiophene，而SJW-E1則是使用alkyl-ethylenedioxythiophene。二個錯合物皆採用One-pot的合成法合成，並利用NMR、IR與Mass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。在AM1.5光源照射下，以SJW-E1以及CYC-B3敏化之電池元件的光電轉換效率分別為9.02 %與7.39 % (相較於N3電池的8.42 %)。而SJW-E1效率比CYC-B3高，是因為SJW-E1的輔助配位基上的ethylene-dioxy group可以提供額外的共軛系統到噻吩上，使其最大吸收波長紅位移且吸收係數亦增加。ethylene-dioxy group的另一個功能是其為好的電子供給者，可避免染料激發後電子電洞再結合。

關鍵字

染料敏化太陽能電池 ； 錯合物 ； 光敏化劑

並列摘要

Two new ruthenium complexes (SJW-E1, and CYC-B3) with the general chemical formula of [Ru(dcbpy)(L)(NCS)2] where dcbpy is 4,4’-dicarboxylic acid-2,2’-bipyridine and L is 4,4’-bis-(4’-octyl-3,4- ethylenedioxythiophene-2-yl)-2,2’-bipyridine or 4,4’-bis-(4’-octyl-tri- thiophen-2-yl)-2,2’-bipyridine were prepared and well characterized. The performance of these two dye sensitized dye-sensitized solar cells (DSCs) was also explored. These complexes were synthesized via the typical one-pot synthesis and identified with NMR, IR and Mass spectroscopies. 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. Under the illumination of AM1.5 stimulated light, the photon-to-current conversion efficiency of SJW-E1 and CYC-B3 sensitized cells was 9.02 % and 7.39 % whereas 8.42 % is obtained for the N3 sensitized cell. The efficiency of SJW-E1 sensitized solar cell is higher than that of CYC-B3 sensitized solar cell, because of the ethylene-dioxy group on the ancillary ligand of SJW-E1 is able to offer extra conjugated length to thiophene. Therefore, the SJW-E1 has its λmax more red-shifted and higher absorbance coefficient compared to CYC-B3. In addition, the ethylene-dioxy group could avoid electron-hole recombination due to its good electron donating ability. These characteristics make SJW-E1 a good photesensitizer for DSCs.

並列關鍵字

Dye-Sensitized Solar Cells ； Complexes ； Photesensitizer

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