本文透過暫態光電壓(Transient phtovoltage簡稱TPV )及暫態光電流(Transient phtocurrent簡稱TPC)量測技術以探討鈣鈦礦太陽能電池的載子動力學。首先第一部分，透過TPV量測技術量測出MAPbI3 、 FACsPbI3和FACsPbI3+CsCOOH三種鈣鈦礦太陽能電池的載子活期，在一個太陽光強度下其載子活期分別為384、657和743 ns。其中FACsPbI3+CsCOOH元件具有較高的載子活期和短路電流密度(Jsc)，顯示出加了擬鹵化物甲酸銫的FACsPbI3具有較好的結構品質以及較少的非輻射複合中心缺陷的影響。在小於一個太陽光強度下觀察到兩階段的TPV衰減行為，較快的衰減時間歸因於自由載子的複合，較慢的部分則是因為離子遷移影響複合速率所造成。另外也針對了離子種類與離子在鈣鈦礦層內遷移做了詳細的討論。
第二部分利用TPC量測技術量測出電荷提取時間，其中FACsPbI3及FACsPbI3+CsCOOH元件顯示出較短的提取時間，暗示具有較短的電荷傳輸時間或較快的電荷傳輸。再結合TPV及TPC的實驗結果所進行的微分電容分析可以得到鈣鈦礦層內的電荷載子密度，相對於MAPbI3 (3.721015 cm-3)和FACsPbI3 (8.081015 cm-3)的電荷載子密度，FACsPbI3+CsCOOH具有較高的電荷載子密度(1.45×〖10〗^16 cm-3)。最後再透過載子活期與相對應的電荷載子密度作圖分析可得反應級數Φ，結果顯示FACsPbI3+CsCOOH具有最低的複合率和缺陷密度。總結TPV和TPC的實驗結果，加了擬鹵化物甲酸銫的FACsPbI3成功改善了其載子活期及傳輸時間，也因此獲得較高的光電轉換效率。

Transient photovoltage (TPV) and transient photocurrent (TPC) measurement techniques were used to investigate carrier dynamics of perovskite solar cells. In the first section, carrier lifetime were measured by TPV for three different perovskite materials including MAPbI3, FACsPbI3 and FACsPbI3+CsCOOH cells. Carrier lifetimes of the three perovskite solar cells under one sun light intensity are 384, 657, and 743 ns, respectively. The FACsPbI3+CsCOOH cell with longer carrier lifetime is consistent with the higher short-circuit current (Jsc), which indicates better crystalline quality and less non-irradiative centers compared to other devices. A two-step TPV decay was observed at lower light intensity condition. The rapid and slow decay processes are attributed to the free carrier recombination and ion immigration respectively.
For the second part, carrier extraction time was measured and analyzed by TPC. The FACsPbI3 and FACsPbI3+CsCOOH cells still exhibits shorter charge extraction time, which implies shorter charge transit time or faster carrier transport. Differential capacitance analysis further confirmed a higher charge carrier density at 1.451016 cm-3 of FACsPbI3+CsCOOH compared to the values at 3.721015 cm-3 of MAPbI3, and 8.081015 cm-3 of FACsPbI3. The carrier lifetime versus charge carrier density plot also indicates the FACsPbI3+CsCOOH cell with lower recombination rate and lower defect density. Overall the TPV and TPC investigation manifest that cesium formate doping successfully improve carrier lifetime, charge transport, and thus photoelectric conversion efficiency in FACsPbI3 solar cells.

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