| 摘要: | 染料是染料敏化太陽能電池中的重要組成，扮演著決定光電流大小的角色。以釕金屬為中心的高效率錯合物染料通常是以兩個雙芽基bipyridine 及兩個單芽基 Thiocyanate ligand (NCS)所組成的六配位錯合物，但單芽基的 NCS 配位穩定度低。本論文的研究重點即用bipyridine-pyrazolate ligand 取代NCS ligand合成出含一個4,4′-dicarboxy-2,2′-bipyrdine (dcbpy)及兩個 bipyridine-pyrazolate 之六配位釕錯合物 CYC-B29。CYC-B29 有三種異構物 CYC-B29-1、CYC-B29-2、CYC-B29-3，本論文利用 1H-NMR 鑑定 CYC-B29-1、CYC-B29-2 及 CYC-B29-3 的結構。UV-Vis 測量其吸收光譜，三個異構物有不同的最大吸收波長分別為539 nm、520 nm 及 521 nm，但DFT 理論計算所得到的前沿軌域電子雲分布相似，HOMO 皆主要落於金屬中心，LUMO 則落於 dcbpy。由 CYC-B29-1、CYC-B29-2 CYC-B29-3 所組成之 DSSCs 電池元件光電轉換效率分別為 4.71 %、1.03 %及4.84 %。CYC-B29-3 有最小的暗電流且在光陽極有最多的染料吸附量而有最高的光電轉換效率。Dye is an important component in the dye-sensitized solar cells which determine the photocurrent of the device. The Ruthenium, based on high-efficiency dyes are, usually six-coordinated complexes are composing of two Bidentate bipyridine ligands and two monodentate Thiocyanate(NCS) ligands. However, the stability of thiocyanate is poor. This thesis focused on using bipyridinepyrazolate ligand to replace NCS ligand. A Ru-based 6-coordintated complex (CYC-B29) coating 4,4'-dicarboxy-2,2'-bipyridine (dcbpy) ligand and two bipyridine-pyrazolate ligands has been prepared. Unsymmetric CYC-B29 has three isomers CYC-B29-1, CYC-B29-2, and CYC-B29-3. The structure of CYC-B29 was determined by 1H-NMR spectroscopy. UV-Vis absorption spectrum showed that the absorption maxima of the three isomers were 539 nm, 520 nm, and 521 nm respectively. Nevertheless the electron density distribution of the frontier orbital calculated by the density functional theory (DFT), for CYC-B29-1, CYC-B29-2, and CYC-B29-3 are similar. HOMO contributed mainly on the metal centre, and LUMO contributed from dcbpy ligand. The conversion efficiency of dye sensitized solar cells based on CYC-B29-1, CYC-B29-2, and CYC-B29-3 are 4.71 %, 1.03 %, and 4.84 % respectively. CYC-B29-3 has the smallest dark current and the largest dye-loading in photoanode, therefore has the highest photo-to-current conversion efficiency. |
