本研究將丁腈(butyronitrile，BN))作為 系統電解液的溶劑來取代傳統有毒且易揮發的溶劑乙腈(acetonitrile，ACN)，丁腈的低毒性、不易揮發和黏滯性低的特性讓它適合應用在染料敏化太陽能電池(DSCs)的電解液中，而且它略高的施子數DN(Donor number)讓它比起其他溶劑之電解液系統在開路電壓上有更大優勢，使丁腈(BN)電解液系統勝過常見的3-甲氧基丙腈(3-methoxypropionitrile，MPN)電解液系統在室內光環境(200 lux)條件下的光伏表現。
由於低光環境下光載子數量大幅減少，為了因應照光環境的改變，我們降低BN電解液中的I2碘濃度避免過多的載子阻礙傳輸，接著調整電解液中添加物TBP、GuSCN之濃度比例來改變DSCs中光電極TiO2之特性，如:(1)在熱力學上，平移TiO2之導帶能階位置;(2)在動力學上，減緩電解液中 與TiO2界面電子復合之速率。平衡兩種添加物對於DSCs的影響找出最佳的電解液組成後，在室內光200 lux的照光環境下搭配Z907(D907)染料光電轉換效率可以達到13.43%。
以溶液的方式將小分子酸加入染料中以修飾TiO2的表面，小分子酸以化學吸附在表面可以抑制元件的暗電流並進一步提升元件之填充因子(Fill factor)，改善DSCs開路電壓且能維持短路電流，以不同濃度之DINHOP(Dineohexyl phosphinic acid)與Z907(D907)染料共浸泡後，最終以0.3 mM之DINHOP共浸泡效果最好，大幅的改善元件之開路電壓表現。再將BN電解液系統應用在Dyesol、IPA、IPA/OCT(混和型漿料)三種不同顆粒大小及形狀漿料之工作電極，由研究結果顯示隨著漿料的不同其TiO2的導帶能階位置和載子的界面傳輸特性會跟著改變，三者之中以使用IPA為工作電極之元件有最好的光伏響應。綜合這些影響和優化後，發現BN電解液系統能夠勝過MPN電解液系統，在室內光200 lux的照光條件下分別達到光電轉換效率15.46%與14.21%。

Recently, non-volatile solvents are introduced to prepare electrolyte for dye-sensitized solar cells (DSCs) because of their environmentally friendly property, among which butyronitrile (BN) solvents is a promising candidate for low-volatile electrolyte. Compared to the conventional solvent of acetonitrile (ACN), BN has relatively high boiling point. Although 3-methoxypropionitrile (MPN) and BN are non-volatile solvents, electrolytes based on BN shows more greater performance in mass transport in virtue of its low viscosity[1]. In the report, we employ BN-based electrolyte for DSCs to optimize including electrolyte composition, coadsorbents and TiO2 paste under dim-light luminance of 200 lux. Under low light intensities, the constituent of electrolyte has remarkable influence on the DSCs performance so we optimize the concentration of iodine and additives in the electrolyte to reach the best performance. The power conversion efficiency(PCE) of DSCs under dim-light intensity can be significantly improved when modulating the electrolyte composition and the surface property. Under dim-light illumination(200 lux), the power conversion efficiency of 15.46 % and 14.21 % of PCE can be achieved for devices using BN-based and MPN-based electrolyte with D907 dye, respectively.

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