新世代鈣鈦礦太陽能電池在短短幾年內效率已突破 22%，以非常快的速度逼近矽晶太陽能電池，而在高效率的鈣鈦礦太陽能電池中，緻密、無孔洞、大晶粒、高結晶品質的鈣鈦礦層，一直是科學家研究的重點。本研究中使用 Single-Step 配合反溶劑法製作高品質鈣鈦礦層，研究發現反溶劑甲苯旋塗後會與鈣鈦礦前驅液溶劑因表面張力差形成「馬倫哥尼應」，此效應會使 MAI-PbI2-DMSO 中間相分佈不均，造成孔洞與結晶缺陷，為解決此效應我們利用一種簡單的延遲熱退火機制，可有效使中間相均勻化，在 100℃退火後形成高品質高覆蓋率的鈣鈦礦結晶。研究藉由 SEM, XRD, AFM 與 EIS 等儀器分析，找出最佳的優化參數並製作成電池元件，電池效率從無延遲退火的 13.58%提升至最佳參數延遲 40min 退火的 18.02 %(增益 32.69%)。
此外，為了取代傳統高毒性的反溶劑與加快製程速度，本研究選用低毒性的反溶劑乙酸乙酯(EA)，利用其低表面張力高蒸發速度等優勢，快速製備高品質的鈣鈦礦層，研究發現藉由調整 EA 旋塗的用量可以有效解決 EA 揮發太快所造成的鈣鈦礦層孔洞缺陷現象，調整後以 500ul 反溶劑用量有最佳 16.39%的效率，雖然效率比不上優化後的甲苯，但在電池元件的製程中可縮短馬倫哥尼效應需要等待的時間，有助於降低大量製程鈣鈦礦太陽能電池的時間與製作成本。
最終，本研究結合延遲熱退火機制與奈米結構 FTO 基板技術，藉由提高鈣鈦礦層品質、電極與電子傳輸層接觸面積以及增益鈣鈦礦層吸光效率等優點，成功地製造出具有高電流(23.17mA/cm2)、高電壓(1.07V)、高 FF(77.62%)、低遲滯指數(0.05)以及效率高達 19.29%的高效率鈣鈦礦太陽能電池。

In this study, we used Single-Step and anti-solvent methods to fabricate a MAPbI3-based perovskite solar cell. However, using the toluene as an anti-solvent will induce the "Marangoni effect" due to difference of the surface tension at the interface between the dripped solvent and the perovskite precursor. This effect will cause non-uniform distribution of the intermediate phase (MAI-PbI2-DMSO) which will form unexpected voids inside the perovskite layer leading to a low-quality perovskite film. Therefore, we introduce a simple delayed-annealing method to achieve a high-quality and high-coverage perovskite layer which can significant improve the non-uniform distribution of the intermediate phase. We use the
SEM(Scanning Electron Microscope), XRD(X-ray Diffractometer), AFM (Atomic Force Microscopic) and EIS（Electrochemical Impedance Spectroscopy） to observe and analyze the quality of perovskite films. In comparison with the control sample (without delayed-annealing), the power conversion efficiency (PCE) will increase from 13.58% to 18.02% (enhanced 32.69%) with the sample annealing at 100℃ for 40 min. Moreover, to replace the traditional toxic anti-solvent and realize a rapid process of forming a high-quality perovskite film, a low-toxic anti-solvent ethyl acetate (EA) is chosen to rapidly fabricate high-quality perovskite layers with the advantages of low surface tension and high evaporation rate. After using EA as the alternative anti-solvent, the highest PCE is 16.39% with dripping the EA of 500ul.
Although the PCE is lower than using traditional toluene as the anti-solvent, it’s unnecessary treating with annealing process for 40 mins to suppress the Marangoni effect which has benefits to reduce the time and cost of fabricate the perovskite solar cells.
Additionally, we further incorporate with nanostructures on the FTO surface to increase the absorption of perovskite layer and contact area between FTO surface and mesoporous layer which can effectively increase the electron transport efficiency.
Finally, the PCE will eventually increase to 19.29% while the sample treated with delayed-annealing method and introduced with the patterned-FTO substrate.

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