本研究之第一部分為建立FAPbI3鈣鈦礦太陽能電池系統，過去文獻以多步驟熱處理方式(80℃,3min--120℃,5min--70℃,22min)來製備FAPbI3鈣鈦礦薄膜，以降低甲胺鹽酸鹽(MACl)的揮發速率，減少孔洞的產生，其效率高達20.2％。然而文獻並未描述製備過程中的細節，依照其實驗步驟製作，所展現的光電轉效率最高為16.5％。因此希望進透過調整熱處理程序以及反溶劑體積以控制鈣鈦礦薄膜的成核成長及相組成，進而製備出與文獻相當的光電轉換效率。結果發現，從多步驟熱處理調至一步驟熱處理(100℃, 60 min)，其Voc與光電轉換效率與文獻相當(1.05 V)，冠軍效率為20.1％。
第二部分將甲胺鹽酸鹽(MACl)溶於氯仿和異丙醇的混合溶劑以作為鈣鈦礦層的表面修飾溶液，透過MA陽離子和氯陰離子分別鈍化負電缺陷(VFA-)與正電缺陷(VI+)。經MACl修飾，Voc從1.05 V提升至1.09 V，光電轉換效率從19.8%提升至20.7%(冠軍效率為21.03%)。

The first part of this research is to establish a FAPbI3 perovskite solar cell system. In the past, the literature used a multi-step heat treatment method (80℃, 3min→120℃, 5min→70℃, 22min) to prepare FAPbI3 perovskite thin films to reduce the volatilization rate of MACl and reduce the generation of holes, and its efficiency is as high as 20.2%. However, the literature does not describe the details of the preparation process. According to the experimental steps, the photoelectric conversion efficiency displayed is up to 16.5%. Therefore, we want to control the nucleation,growth and phase composition of the perovskite film by adjusting the heat treatment procedure and antisolvent volume, thereby producing a photoelectric conversion efficiency comparable to the literature. The results showed that when the multi-step heat treatment was adjusted to one-step heat treatment (100°C, 60 min), the Voc and photoelectric conversion efficiency were equivalent to those in the literature (1.05 V), and the championship efficiency was 20.1%.
In the second part, Methylammonium chloride (MACl) in a mixed solvent of chloroform and isopropyl alcohol as a surface modification solution for the perovskite layer, and the negative electron defects (VFA- ) and positively charged defects (VI+). After modification by MACl, Voc was increased from 1.05 V to 1.09 V, and the photoelectric conversion efficiency was increased from 19.8% to 20.7% (champion efficiency is 21.03%).

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