隨著科技的進步與文明的發展，人類對能源的需求量與日俱增，因此能源議題越來越重要。鈣鈦礦太陽能電池(Perovskite Solar Cell，簡稱PSC，光電轉換效率最高達23.3%)的主要吸光層(Perovskite膜)合成方法簡單，因此有低的製作成本且效率與矽晶圓太陽能電池差不多。但由於PSC中的鈣鈦礦膜(Psk)易與水作用而分解，使得所組裝的元件在大氣下不穩定，因此提高鈣鈦礦太陽能電池的長時間穩定性為近幾年的研究重點之一。本研究透過使用具有較長碳鏈的分子，如：Butyl ammonium iodide (BAI)、Ammonium valeric acid iodide (AVAI)、Phenethylammonium iodide (PEAI)，分別溶於異丙醇(IPA)中作為表面修飾劑，利用在3D鈣鈦礦膜(CH3NH3PbI3)表面上形成較疏水的2D鈣鈦礦薄膜去修飾鈣鈦礦膜，提高元件在大氣下的長時間穩定性，實驗結果顯示以PEAI做表面修飾後的鈣鈦礦膜(PPsk)所組裝的元件有最佳的長時間穩定性與最大的光電轉換效率(達13.18%)，使用PPsk的元件在未封裝下放置於相對溼度約45%的環境中48天後仍有7.26% (最高效率的55%)的光電轉換效率。

The issue of energy sources becomes more and more vital since the mankind have more demand in energy than ever. The active layer (perovskite film, Psk) of Perovskite Solar Cell (PSC) with the conversion efficiency up to 23.3%, close to that of and Silicon based solar cell) is easy to prepare. Therefore, PSC has a lower production cost, can be a non-expensive green energy source. Nevertheless, Psk was demaged easily by water, making PSC unstable under the ambient atmosphere. Consequently, improving the long-term stability of PSC is one of the hot research topic in recent years. Here we used molecules with longer Alkyl chain, such as Butyl ammonium iodide (BAI), Ammonium valeric acid iodide (AVAI) and Phenethylammonium iodide (PEAI) as the Psk surface-treatment (passivation) agents by forming a hydrophobic 2D perovskite thin film on the surface of the 3D perovskite (CH3NH3PbI3) to form a 2D/3D perovskite (PPsk). PSC based on PPsk active layer has higher long-term stability under the ambient atmosphere compared to that based on Psk. Cell based on PEAI passivated Psk has the longest long-term stability and highest efficiency (up to 13.18%). The unencapsulated device have an efficiency of 7.26% (ca. 55% of the highest efficiency) after sitting in the environment with ca. 45% relative humidity for 48 dayswhile the efficiency of cell based on Psk is lost totally.

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