本研究旨在開發一適用於染料敏化太陽能電池之高效能可印刷式電解質，探討此電解質於太陽光下之最佳條件，並應用於室內光環境與大尺寸次模組元件。實驗中搭配N719染料，以低揮發性的3-甲氧基丙腈(MPN) 製備含I-/I3-氧化還原對之電解質溶液，並利用聚氧化乙烯(PEO)及聚甲基丙烯酸甲酯(PMMA)共混物作為增稠劑，提高電解質黏度使其具有可印刷之特性。實驗結果顯示，要使電解質具備可印刷特性，PEO為必要成分，PMMA的添加則可提高電解質的導電性以及元件的光電轉化效率，但過多的PMMA會導致電解質黏度下降，使其在印刷製程中發生溢流行為，不利於製備元件。而藉由增稠劑含量的調控，研究發現在PEO/PMMA的比例為7:3時添加9wt%高分子共混物，電解質具有印刷式製程所需之最低黏度16.94 Pa⸱s，且以此可印刷式電解質所製備之元件在標準光源(100mW/cm2)下有最佳光電轉換效率8.49%。研究結果亦發現，使用印刷式製程來導入電解質，可使高黏度電解質在中孔洞結構的二氧化鈦光電極中有較佳的滲透性，提升元件開路電壓。此外，當以10 wt%之TiO2奈米粒子作為可印刷式電解質的添加劑，元件效率更可提升至9.12%，高於液態元件的表現(8.33%)。若將電池元件於60oC高溫環境下進行穩定性測試，發現純印刷式元件具有最佳的穩定度，在經過500小時後仍可維持87%之初始效率。本研究進一步應用此印刷式元件於室內光源下發電，並對光電極TiO2薄膜厚度進行調整，結果顯示此一元件在200 lux室內光源下之最大輸出功率密度可達10.65 μW/cm2。最後，配合上述最佳化條件製備可印刷式次模組元件，在標準光源下使用陣列式次模組之光電轉換效率可達6.78%，而在200 lux室內光源下採用長方型次模組之最大輸出功率密度則可達8.68 μW/cm2。

In this study, printable electrolytes containing I-/I3- redox couples are developed with N719 dye for dye-sensitized solar cell (DSSC) applications. 3-methoxypropionitrile (MPN) is employed as a solvent with low volatility in order to reduce the electrolyte evaporation during the fabrication of solar cells. Two kinds of polymers, poly (ethylene oxide) (PEO) and poly (methyl methacrylate) (PMMA), are added simultaneously into electrolytes to regulate the viscosity achieving the requirement of printing. The results show that PEO is the required material to form the electrolyte paste, and the addition of PMMA can increase the ionic conductivity of the electrolyte to improve cells performance. However, a higher ratio of PMMA will lead to low viscosity of the electrolyte which is not proper to operate the printing process. The experimental results show that the optimal PEO/PMMA ratio and the overall polymer amount in an electrolyte are respectively 7:3 and 9 wt% with a limited viscosity of 16.94 Pa⸱s. The DSSC using this printable electrolyte can achieve a power conversion efficiency (PCE) of 8.49% under standard 1 sun irradiation (100 mW/cm2). Also, the viscous electrolyte performs an excellent penetration into TiO2 meso-porous matrix by using printing process, leading to higher open-circuit potential. When 10wt% TiO2 nanoparticle is introduced to the printable electrolyte, the PCE can further increase to 9.12%, which is much higher than that of the liquid cell. In addition, the DSSC employing printable electrolyte displays a stable photovoltaic performance during the aging test at 60 °C for 500 hours. By adjusting the thickness of TiO2 film, a power density (Pmax) of 10.65 μW/cm2 is obtained for the cells under 200-lux illumination. Furthermore, the printable electrolytes are applied to sub-module device under different light irradiation; a PCE of 6.78% and a Pmax of 8.68μW/cm2 are achieved under 100 mW/cm2 and 200-lux illumination respectively.

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