本研究的目的在開發適用於染料敏化太陽能電池(DSSCs)的印刷式電解質，探討此電解質應用在太陽光及室內光源下的最佳條件。為了降低溶劑在電解質印刷製程上揮發，本研究使用低揮發性的3-甲氧基丙腈(MPN) 為溶劑，製備含I-/I3- 氧化還原對的電解液，再利用聚氧化乙烯(PEO)及聚偏氟乙烯(PVDF)作為增稠劑，藉由聚合物含量的調控來提升電解質之黏度，使電解質具有可印刷的特性。實驗結果顯示，要使電解質具有可印刷性質，PEO是必要的成份， PVDF的添加則可以提高電解質的導電性以及電池的光電轉化效率，但太多PVDF的添加則會使電解質成為膠態，失去可印刷性質。藉由聚合物含量的調控得知，在添加9wt%高分子共混物PEO/PVDF的比例為8:2時，此印刷式電解質所製備的元件在標準光源(100 mW/cm2)下有最佳的光電轉化效率(8.32%)。若再以二氧化鈦奈米粒子(4wt %)作為此電解質的添加劑，元件效率可再提升至8.91%，高於液態元件的表現。此一印刷式電池於60oC及高濕高溫環境下進行穩定性測試，經過500小時後元件皆可維持良好的穩定度。為了將印刷式DSSCs應用於室內光源發電，需要對電解質中之碘濃度與二氧化態薄膜厚度進行調整，結果顯示此一電池在200 lux下之輸出功率密度可達9.74μW/cm2。此一研究亦將上述小元件探討所得之最佳條件應用於次模組元件之製作，在標準光源下陣列式次模組之轉換效率可達6.45%，在200 lux室內光源下採用大面積次模組之輸出功率密度可達7.84μW/cm2。

The purpose of this study is to develop printable electrolytes for dye-sensitized solar cell (DSSC) application and, furthermore, investigate the optimal electrolyte compositions for both sunlight and twilight illuminations. To avoid the evaporation of the electrolyte in the printing process, 3-Methoxypropionitrile (MPN) is used as the solvent to prepare the electrolyte containing I-/I3- redox couple. Poly(ethylene oxide) (PEO) and poly(vinylidene fluoride) (PVDF) are utilized as viscous agents to regulate the viscosity of the electrolyte pastes for operating by the printing process. The results show that PEO is a required material to prepare the electrolyte pastes, and the addition of PVDF can increase the ion conductivity of the electrolytes. However, addition a high amount of PVDF will lead to the gelatinization of the electrolyte which cannot be operated by printing process. The optimal PEO/PVDF ratio and their overall addition amount for preparing the electrolyte are 8:2 and 9 wt%, respectively. The corresponding cell can achieve a power conversion efficiency (PCE) of 8.32% under 100 mW/cm2. When 4wt% TiO2 nanoparticles is introduced as fillers of the printable electrolyte, the PCE can further increase to 8.91% which is higher than that obtained for the corresponding liquid cell. The DSSCs prepared by the printing process are stable under the stability test at high temperature (65oC)/high humidity conditions. By adjusting the composition of the redox couple, the prepared DSSCs are also applied for operation under room-light illumination. A power density (Pmax) of 9.74μW/cm2 is obtained for the cell under 200 lux illumination. Finally, the printable electrolyte is also applied to fabricate sub-module cells and a PCE of 6.45% is achieved under 100 mW/cm2. Under 200 lux illumination, the sub-module cell has a Pmax of 7.84μW/cm2.

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