| 摘要: | 反式錫鈣鈦礦太陽能電池(Tin perovskite solar cells, 簡稱TPSCs)中錫鈣鈦礦吸收層容易受到水氣分解使元件長時間穩定性不佳，部分原因是使用會吸水的鹽類摻雜之有機電洞傳遞層(HTL,如:PTAA、PEDOT:PSS)，因此開發不受水氣影響且具有熱穩定、寬的能隙、高的穿透度和高電洞遷移率等之無機HTLs成為重要研究主題，但無機材料與錫鈣鈦礦層存在介面相容性的問題須解決。本研究以真空熱蒸鍍製備SnO膜做為電洞傳遞層，並透過UV-O3後處理SnO降低Valence band至-5.33 eV與本實驗室所使用錫鈣鈦礦層FA0.98EDA0.01SnI3的Valence band -5.80 eV接近，以減少電洞傳遞時的能量損失，SnO 做為電洞傳遞層所組裝成元件的光伏表現中為 Jsc = 20.99 mA/cm2，Voc = 0.63 V，FF = 52 %，PCE =6.97%。為解決SnO與錫鈣鈦礦介面的問題。使用具有兩性性質高分子PDTON做為電洞傳遞層與錫鈣鈦礦層間的介面層。從FTIR光譜可見加入SnI2之PDTON的ester C-O stretching 和amine C-N stretching，兩者皆往高波數位移，顯示PDTON上之氧與胺基的孤對電子，能與錫鈣鈦礦層未飽和配位的Sn2+作用。經SCLC理論計算得到SnO/PDTON電洞遷移率為1.74*10-4 cm2V-1s-1大於PEDOT:PSS的電洞遷移率1.45*10-4 cm2V-1s-1，FA0.98EDA0.01SnI3沉積於玻璃或SnO/PDTON之TRPL數據顯示，載子生命期由 0.97 ns 縮短至0.25 ns，代表PDTON使SnO能更有效的萃取傳遞錫鈣鈦礦的電洞。以SnO/PDTON 做為電洞傳遞層所組裝之元件的光伏參數為 Jsc = 23.39 mA/cm2，Voc = 0.59 V，FF = 67%，PCE =9.19%，與SnO做為電洞傳遞層所組裝之元件相比，FF得到明顯變化。而以PEDOT:PSS做為電洞傳遞層所組裝之元件光伏參數為 Jsc = 24.57 mA/cm2，Voc = 0.53 V，FF = 68%，PCE =8.93%。以SnO/PDTON做為電洞傳遞層所組裝之元件在沒有封裝的情況下放置在氮氣手套箱中並在室內光照下放置 3240 小時，仍維持其原始效率的 76%，元件表現良好的穩定性，而PEDOT:PSS做為電洞傳遞層所組裝之元件在相同條件下僅維持原效率66%。可見SnO/PDTON與PEDOT:PSS之光伏表現相似。而大氣下穩定性測試中，將元件置於溫度27℃、相對濕度40%的環境中， SnO/PDTON做為電洞傳遞層所組裝之元件經過兩小時仍能維持原效率的64%，而PEDOT:PSS做為電洞傳遞層所組裝之元件在相同條件下僅維持原效率8%，顯現無機材料做為電洞傳遞層的穩定性優勢。;The perovskite absorber layer in tin perovskite solar cells(TPSCs) is susceptible decomposition by water, partically due to the hole transoorting layer(HTL) (e.g., PTAA, PEDOT:PSS)was generally doped with hyderophilic salt.Searching for high stability, transpartent inorganic HTL is an important work for advancing TPSCs. Moreover, these may have an interacial problem between inorganic HTLs and perovskite layers. In this study, SnO films were prepared by vacuum thermal evaporation as the hole transport layer, and the valence band of SnO was lowered to -5.33 eV which is close to the valence band of -5.57 eV of the perovskite layer FA0.98EDA0.01SnI3 used in our laboratory after treat with UV-O3 for 20 min, to reduce the energy loss during hole transport. The photovoltaic performance of the device base on SnO HTL is Jsc = 20.99 mA/cm2, Voc = 0.63 V, FF = 52%, and PCE = 6.97%. To solve the interface problem between SnO and perovskite. The amphiphilic polymer PDTON was used as the interface agent. FTIR spectra show the ester C-O stretching and amine C-N stretching shifted to low wavenumbers, when mixed with SnI2 indicating that the lone pair of electrons on the oxygen and amine groups of PDTON can interact with the unsaturated coordinated Sn2+ in tin perovskite. The TRPL data of FA0.98EDA0.01SnI3 deposited in glass or SnO/PDTON showed that the carrier lifetime is 0.97 ns and 0.25 ns, respectively which means that SnO/PDTON can effectively extract the holes of tin perovskite. The photovoltaic parameters of SnO/PDTON based device are Jsc = 23.39 mA/cm2, Voc = 0.59 V, FF = 67%, and PCE = 9.19%. The PV parameters of the PEDOT:PSS based device are Jsc = 24.57 mA/cm2, Voc = 0.53 V, FF = 68%, and PCE = 8.93%. When device used SnO/PDTON HTL was placed in the nitrogen filled glove box without encapsulating and under room light illumination for 3240 hours, 76% of its original efficiency was maintained. While cell based on PEDOT:PSS HTL lost 34% of the initial efficiency. In the atmospheric stability test, when the device was placed in the environment of 27℃ and 40% relative humidity, SnO/PDTON based device maintained 64% of its original efficiency after two hours, whereas PEDOT:PSS based device maintained only 8% of its original efficiency under the same conditions, which demonstrates the stability advantage of inorganic materials as the hole propagation layer. |
