本論文合成出一系列 (HY) 有機染料，是以 dithieno[3,2-b:2′,3′-d] thiophene 作為電子予體 (electron donor)，2-cyanoacrylic acid為電子受體 (electron acceptor)， oligothiophene 為分子結構中間之共軛架橋 (conjugated spacer) 。另外，在DTT或oligothiophene接上長碳鏈，除了可以增加染料之溶解性，也可利用此疏水性長碳鏈來阻止電解液中的I3－接近TiO2表面，而抑制暗電流的發生與增加元件的穩定性。組裝成的染料敏化太陽能電池 (dye-sensitized solar cells, DSSCs) 呈現不錯的光電轉換效率，其效率範圍為2.57−5.83 %。在相同條件下和N719染料的元件比較，可達N719染料元件效率的41−80 %。在本論文中可以觀察出，大部分HY染料分子的共軛長度越長，其莫耳吸收係數 (ε) 越大，吸收波長 (λmax) 也較紅位移，但效率並非完全成正比。另外，由理論計算數據可推測接在oligothiophene上的碳氫長鏈，其位置可能會破壞分子的平面性及影響染料分子在TiO2上的吸附，而影響電池效率。 A series (HY) of dyes incorporating dithieno[3,2-b:2′,3′-d]thiophene as the electron donor, 2-cyanoacrylic acid as the electron acceptor, and oligothiophene moiety as the conjugated spacer have been synthesized and characterized. The hydrophobic hexyl chains not only increase the solubility of the dyes in organic solvents, but also help to blockade the hydrophilic I3－ ions from approaching the TiO2 surface and increase the stability of devices as well. Dye-sensitized solar cells (DSSCs) using these dyes as the sensitizers exhibited good conversion efficiencies. The efficiencies of the devices based on HY series range from 2.57−5.83%. These values which reach 41−80% of N719-based device fabricated and measured under similar conditions. The molar extinction coefficient (ε) and absorption wavelength (λmax) of the sensitizers normally increase as the conjugated spacer increases，though the cell efficiency does not follow the same trend. Theoretical computation results indicated that the hexyl hydrocarbon chains may degrade the coplanarity of the dye molecule and result in a lower efficiency.
