在本論文中,使用 cross-coupling方法合成了一系列應用於染料敏化太陽能電池中的多環芳香族紫質光敏劑,並探討這些紫質光敏劑部分的光譜學以及電化學性質。另外,為了減少紫質光敏劑吸附在二氧化鈦奈米粒子上所產生之堆疊現象,我們選用在結構上立體阻礙較大的紫質分子 Zn(t-bu)BPP [10,20-bis-(3,5-di-tert-butyl-phenyl)porphinato zinc(II)] 作為光敏劑的主要發色團。 在紫外光-可見光吸收光譜的探討部份,在紫質分子的 mseo-位置以乙炔基做為spacer group 接上雜環類或是多環類取代基後,吸收峰會產生紅移且變寬的現象,其中又以取代基為 fluorenyl 和 acenaphthenyl 的 Zn-2 與 Zn-4 的吸收峰紅移程度最為顯著。在螢光放射光譜中,也可以觀察到相同趨勢的紅移現象,這是因為紫質分子的 π 共軛系統延長所導致。 在電化學探討部份,接上不同雜環類或是多環類取代基的紫質分子之氧化還原電位彼此都相當類似,表示這些紫質光敏劑的能隙相當接近,不同的雜環類或是多環類取代基對於紫質分子的電化學性質影響程度相當接近。
A series of heterocyclic group or polycyclic group substituted porphyrins are successfully synthesized by cross-coupling method and their UV-Vis absorption and redox properties are studied. In order to decrease the aggregation of porphyrin sensitizers upon adsorbing on nanocrystalline TiO2 films, we chose a more steric hindered porphyrin, Zn(t-bu)BPP [10,20-bis-(3,5-di-tert-butyl-phenyl) porphinato zinc(II)]. The UV-Visible absorption spectra of the porphyrin sensitizers show significant red shift of the Soret and Q band, especially in the case of fluorene and acenaphthene substituted porphyrins. These porphyrin sensitizers also show significant red shift in their fluorescence emission spectra. Upon CV and DPV measurements, the reduction and oxidation potentials of these porphyrins are similar to each other. This suggests that different heterocyclic and polycyclic ethynyl substitutes have similar effects on redox properties of the complexes.