近年來，傳統三明治結構染料敏化太陽能電池搭配鈷電解質在AM 1.5G的照光下元件最高轉換效率可達到14.3%，然而，由於一般導電玻璃成本較高且無法大面積量產。因此，越來越多團隊逐漸將目光投入於單一片式染料敏化太陽能電池，從一般傳統碳材料到導電高分子Poly-3,4-Ethylenedioxythiophene(PEDOT)替代導電玻璃作為電極，此外目前在AM 1.5G的照光下最高轉換效率為7.73%。本研究將透過聚苯乙烯球方式製備多孔電極金，發展高效能與低成本單一片式液態染料敏化太陽能電池。
銅電解質Bis-(4,4',6,6'-tetramethyl-2,2'-bipyridine)copper(I)/(II) bis(trifluoromethanesulfonyl)imide ([Cu(tmby)2]2+/1+)系統中氧化還原電位較碘電解質低，搭配染料3-{6-{4-[bis(2',4'-dihexyloxybiphenyl-4-yl)amino-]phenyl}-4,4-dihexyl-cyclopenta-[2,1-b:3,4-b']dithiphene-2-yl}-2-cyanoacrylic acid(Y123)可有效將其驅動能量降至100mV即可將染料100%再生。因此，實驗首次使用銅電解質搭配染料Y123應用於大面積下的單一片式染料敏化太陽能電池，其元件結構FTO/TiO2/30nm–TiO2/400nm-TiO2/Y123 dye/Cu EL/SiO2/PEDOT:PSS/Au，另外透過調整染料濃度Y123、銅電解質濃度、Tetrahydrofuran(TBP)濃度以及催化層poly(3,4-ethylenedioxythiophene) polystyrene sulfonate(PEDOT:PSS)厚度優化元件。最終，實驗進一步將單一片式與傳統三明治式染料敏化太陽能電池相同面積下進行比較，兩種結構分別在AM 1.5G照光下有效面積為1cm2的元件轉換效率為6.7%與5.6%。

In this study, we use Nanosphere lithography (NSL) method to fabricate a porous PEDOT:PSS/Au thin film as a counter electrode in monolithic dye-sensitized solar cell (M-DSCs). In addition, we will optimize the device by tuning the thickness of PEDOT:PSS and the concentration of the dye Y123, the electrolyte Cu(II)(tmby)2TFSI2/1 and the additive TBP to find out the best device performance. At last the device achieved a PCE of 6.7% with Voc of 1.01V, Jsc of 10.05mA/cm2 and FF of 65.5 in the active area 1cm2 under the 1-sun condition.

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