在這研究中，我們展示迄今尚未報導的新型固-固反應製程（SSRP），用於製造超平坦（粗糙度約為12 nm）的大尺吋晶粒（~ 947 nm）CH3NH3PbI3鈣鈦礦薄膜。SSRP只需將碘化鉛膜（PbI2）與碘化甲基銨粉末（CH3NH3I）直接接觸，無需任何化學試劑，於120 ℃正常大氣環境下進行。透過臨場掃描式電子顯微鏡 (SEM) 研究了 SSRP 反應機制。此創新的SSRP為大量製造異質接面的鈣鈦礦太陽能電池，提供了一種簡單的方法，並且我們展示15.27 %的轉換效率（有效面積0.16 cm2）。另一方面，我們研究使用物理氣相沉積（PVD），來製備高品質無機氧化鎳（NiOx）的電洞傳輸層（HTL）薄膜，利用於鈣鈦礦太陽能電池（PSC）上。其中研究發現鈣鈦礦太陽能電池的轉換效率(PCE)與NiOx 電動傳輸層的厚度有很大的相關。透過結構、光學和電性的定量研究來優化NiOx的厚度。在主動面積為11.25 cm2的情況下，鈣鈦礦太陽能電池模組(25 cm2)的PCE為15.1 %，經過36個鈣鈦礦太陽能電池元件測試，其中最高PCE= 18.30 %，開路電壓 (Voc)= 1.05 V，短路電流密度(Jsc)= 23.89 mA/cm2 和72.87 % 的填充因子(FF)，此主動面積較小，為0.16 cm2。在相同環境下，經過40 %的相對濕度(RH）和25 ℃ 於1200小時的穩定性測試後，其轉換效率NiOx相較比有機PEDOT:PSS更高於1.2–1.8倍。

In this study, we show a novel solid-solid reaction process (SSRP), which has not yet been hitherto reported, to fabricate ultra-flat (roughness is about 12 nm) CH3NH3PbI3 perovskite thin film with large grain size (~ 947 nm). The SSRP simply involves directly contacting lead iodide thin film (PbI2) with methylammonium iodide powder (CH3NH3I) without any chemical reagents at 120 ℃ under the normal atmospheric environment. The SSRP reaction mechanism is investigated by an in-situ heating SEM. This innovative SSRP brings an easy approach to large-scale fabrication of planar heterojunction perovskite solar cells and allows us to demonstrate a power conversion efficiency of approximately 15.27 % (active area 0.16 cm2). On the other hand, we also report a perovskite solar cell (PSC) can be benefited from the high quality of inorganic nickel oxide (NiOx) as a hole transport layer (HTL) film fabricated from the physical vapor deposition (PVD) process. The power conversion efficiency (PCE) of PSC is found to depend on the thickness of NiOx HTL. The NiOx thickness is optimized via quantitative investigation of the structure, optical, and electrical properties. With an active area of 11.25 cm2, a PSC module (25 cm2) with a PCE of 15.1 % is demonstrated, while champion device of PCE= 18.30 % with an open voltage (Voc) 1.05 V, short-circuit current density (Jsc) 23.89 mA/cm2, and fill factor (FF) 72.87 % that can be achieved from 36 devices with smaller active areas of 0.16 cm2. After the stability test at 40 % relative humidity (RH) and 25 ℃ for 1200 h, the highest performance NiOx-based PSC is shown to be about 1.2–1.8 times superior to PEDOT:PSS organic HTL-based PSC in the same environment.

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