受到固態電解質(Spiro-OMeTAD)滲透能力不佳的影響，固態染料敏化太陽能電池的最佳厚度約為2微米。因為厚度的限制，所以就必須選擇具有高消光係數(extinction coefficient)的染料分子作為敏化劑，才能達到較好的光捕獲效率。本研究選用D149和SQ2兩種有機光敏染料分子，以不同的溶液體積比，透過雞尾酒混成法達到共增感的效應。實驗結果顯示，雞尾酒染料敏化太陽電池所得到的電流都比單一染料敏化太陽電池為高。根據雞尾酒染料敏化太陽電池的效率測定、入射光電轉換效率(IPCE)及電化學交流阻抗圖譜(EIS)等分析，當D149:SQ2溶液體積比為10:1時，電流和效率有最佳值。
本研究亦進一步探討在不同溶液體積比時，電流獲得提升的機制。由Mercurochrome/SQ2共增感效應和D149/ Chenodeoxycholic acid(CDCA)共吸附效應的結果，與D149/SQ2系統做一個比較，提出雞尾酒混成法電流值提升的可能機制:當混成體積比相近時，由於共增感效應的貢獻使電流獲得提升。然而在混成體積比懸殊時，共吸附效應才是電流值提升的主因。

One observed characteristic of the spiro-based solid-state dye sensitized solar cell is that the efficiency reaches a maximum value when the TiO2 film are only 2μm thickness, and this is caused by the poor pore-filling problem of the solid electrolyte(spiro-OMeTAD). High molar extinction coefficient dyes are therefore desirable in order to make thin solar cells with good light-harvesting. In this study, two organic dye molecular, D149 and SQ2, were selected as the sensitizers. Through co-sensitization of the D149 and SQ2 sensitizers, which are complimentary in their spectral responses, we have obtained a higher photocurrent than for individual dye-sensitized solar cells. By analysis of efficiency measurement, IPCE spectra and EIS spectra showed that when the volume ratio between D149 and SQ2 is 10 to 1, photocurrent and efficiency achieved maximum values.
Furthermore, the mechanism of enhanced photocurrent under different volume ratio was investigated. Compared the results of Mer/SQ2 co-sensitized effect and D149/CDCA co-adsorbent effect to D149/SQ2 system, a possible mechanism was proposed: If the volume ratio is closed, obviously, the contributed photocurrent is caused by the co-sensitized effect. On the other hand, when the ratio different is very large, the co-adsorbent effect is the major cause to increase the photocurrent.

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