鈣鈦礦太陽能電池(Perovskite solar cells，簡稱PSC)，由於組裝過程簡易且材料價格便宜，因此製作成本低而快速發展。至2021年PSC元件已驗證的光電轉換效率已達25.5%。PSC元件中所使用的電洞傳遞層(hole transporting layer, HTL)材料須具備高電洞萃取效率、快速電洞傳遞及與鈣鈦礦層的valence band (VB)與conduction band (CB)能階匹配等特性。Spiro-OMeTAD、P3HT等是常用的PSC HTL材料。本研究利用本實驗室合成之P12、P15、P16、P17、P18、P19、P20、P21等7個高分子作為PSC元件之HTL材料，利用高分子疏水的特性，增加PSC元件的長時間穩定性。將高分子材料溶於高沸點溶劑中使沉積的膜排列具有較高的規則度，並以4-Iso-propyl-4‘-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate (簡稱DPI-TPFB)作為摻雜劑，並在鈣鈦礦(Psk)膜與高分子HTL之間沉積一層2-Bromo-5-hexylthiophene (簡稱BHT)膜以修飾界面並可階梯式將電洞由鈣鈦礦層傳遞至電洞傳遞層，降低電位損耗，增加PSC元件的光電轉換效率，結果以P15及P18的光伏特性比P3HT好。P15膜沉積在Psk上時又比較不會聚集(相對於P18)，可降低電洞在膜上傳遞時發生載子再結合。DPI-TPFB摻雜之P15(DPI-TPFB@P15)的HOMO能階為-5.44 eV與鈣鈦礦膜的VB能階-5.61 eV匹配性比DPI-TPFB@P18更好，因此能更有效率的萃取電洞，以DPI-TPFB@P15膜作為HTL相較於DPI-TPFB@P18膜組裝成元件有更高的Voc值為1.00 V。以DPI-TPFB@P15、DPI-TPFB@P18、及DPI-TPFB@P3HT作為HTLs組裝成元件的光電轉換效率分別為17.08%、11.75、11.63%。若再以BHT作介面修飾，元件的光電轉換效率分別提高至18.17 %、15.03 %、及14.79 %，遲滯因子則分別為9.1 %、6.7 %、13.9 %。

The rapid progress of perovskite solar cell (PSC) is due to it has a simple assembly process, high efficiency and uses few materials, therefore the manufacturing cost is low. The certified power conversion efficiency (PCE) of PSC device has reached 25.5 % in 2021. Hole transporting layer (HTL) used in PSC devices must have high hole extraction efficiency, fast hole transport and the energy level of the frontier orbitals matches with those (valence band (VB) and conduction band (CB)) of the perovskite absorber. Spiro-OMeTAD and P3HT are commonly used HTL materials. In this study, the polymer synthesized by our lab, including P12, P15, P16, P17, P18, P19, P20, and P21, are used as HTL materials for regular PSCs. The hydrophobic properties of polymers film are used to increase the long-term stability of PSC devices. Higher boiling point solvent is used to make the polymer film more ordered, 4-iso-propyl-4'-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate (DPI-TPFB) is used as the dopant, and 2-bromo-5-hexylthiophene (BHT) is used a perovskite/HTL interface passivation agent. P15 film is deposited on the Psk is less aggregated compared to P18 film, which can reduce the recombination of carriers therefore has better photovoltaic performance. The HOMO of DPI-TPFB@P15 is -5.44 eVwhich matches better the VB (-5.61 eV) of perovskite film than those of DPI-TPFB@P3HT and DPI-TPFB@P3HT HTLs. As a result PSC based on DPI-TPFB @P15 HTL has a highest Voc of 1.00 V. The power conversion efficiencies (PCEs) of the PSC based on DPI-TPFB@P15, DPI-TPFB@P18, and DPI-TPFB@P3HT HTLs are 17.08%, 11.75, and 11.63%, respectively. The PCE of the cell based on BHT/DPI-TPFB@P15, BHT/DPI-TPFB@P18, and BHT/DPI-TPFB@P3HT HTLs increase to devices are 18.17%, 15.03%, and 14.79%, respectively. The cell based on BHT/DPI-TPFB@P15 HTL also has the smallest hysteresis index of 6.7% compare to those (9.1% and 14.0%) of the other two cells.

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