| dc.description.abstract | 近年來，因鈣鈦礦光伏電池轉換效率從2009年的3.8%到目前的>21%，效率快速提升引起全球廣泛的關注。因其優異的高吸光系數、低激子結合能、載子遷移率高且電子壽命長以及可調控的能帶隙等，使得鈣鈦礦材料適合作為光伏電池的吸光層。但是鈣鈦礦成膜時的表面覆蓋率和形貌控制，則需藉由調整其成核速率與晶粒成長速率來控制。為了探討此問題，本研究在製備CH3NH3PbI3鈣鈦礦膜時導入不同種類的反溶劑，使反溶劑與原溶液混溶後，將原溶液從不飽和區導向介穩態區或過飽和區，使其快速多處成核。因此，我們選擇了幾種不同的反溶劑，包括甲苯(TL)、氯仿(CF)、氯苯(CB)、二氯苯(DCB)、異丙醇(IPA)。研究發現，若能將鈣鈦礦前驅液快速導向介穩態區，則能製作出較高覆蓋性和表面平整的鈣鈦礦膜，低介電常數(<5) 、低偶極矩（<1）的溶劑更適合用於製作高品質鈣鈦礦膜，例如甲苯（TL）溶劑。選擇對的反溶劑是製作高效率鈣鈦礦光伏電池的重要環節。進而我們發現若將兩種反混合溶劑，能使鈣鈦礦前驅液有更大的驅動力進入介穩態區。因此我們可以藉由滴旋混合反溶劑的方法，得到結晶性佳、高附蓋性且平整的鈣鈦礦膜製作光伏電池，可以有效提升電池的填充因子(FF)與效率。最後我們使以TL/DCB (v/v = 5/5)作為混合反溶劑，製作n-i-p結構鈣鈦礦光伏電池，最佳元件效率可達18.01% (AM1.5G, 100mW/cm2)。另一方面，混合反溶劑法在p-i-n結構中亦有相同的效果，針對p-i-n結構的光伏電池探討，我們更進一步嘗試在混合反溶劑(TL/DCB)中添加微量的PCBM (0.1wt%)，希望能在滴旋過程中修補鈣鈦礦層中的晶界缺陷，提高電子收集效率，以提升元件填充因子(FF)與短路電流(JSC)，在最佳化後的p-i-n結構電池效率可從15.37%提升到16.31% (AM1.5G, 100mW/cm2)。
最後，將優化後的反溶劑條件製備大面積鈣鈦礦層，並結合本實驗室自行設計了5cm x 5cm的玻璃基板內部串聯鈣鈦礦太陽能電池模組(活性面積為10.56cm2)。以n-i-p結構的鈣鈦礦太陽能電池模組效率可以達到14.56%， (AM1.5G, 100mW/cm2)，而p-i-n結構的鈣鈦礦模組可以達到15.02% (AM1.5G, 100mW/cm2)。另外，本研究針對p-i-n結構的光伏模組部分，進一步嘗試改變p層材料，以NiO金屬氧化物薄膜取代PEDOT:PSS導電高分子，模組效率可以達到15.68% (AM1.5G, 100mW/cm2)。 | zh_TW |
| dc.description.abstract |
Recently, hybrid organic-inorganic perovskite solar cells has attracted much attention, as its power conversion efficiency (PCE) has leapt from 3.8% in 2009 to the current world record of 21.0%. This is attributed to its excellent photoelectronic properties such as a remarkably high absorption coefficient; a low exciton binding energy; a carrier diffusion length in the micrometer range, caused by recombination occurring on a timescale of hundreds of nanoseconds; and a tunable energy bandgap. Because of on these properties, the perovskite materials are suitable as light absorbers in the field of solar cells as well light-emitting devices. However, the surface coverage and morphology of perovskite film, controlled by the nucleation rate and the grain growth rate. To solve this problem, this work explores various anti-solvent treatments for the perovskite film. Let the anti-solvent drives the perovskite precursor into the metastable zone or the supersaturation zone. Here, we make a systematic study of different types of anti-solvents including toluene (TL), chloroform (CF), chlorobenzene (CB), dichlorobenzene (DCB), isopropyl alcohol (IPA). We found that an anti-solvent with a low dielectric constant(<5) and low dipole moment(<1) is most the suitable for perovskite solar cell preparation, such as toluene. Therefore, selection of the anti-solvent become an important factor when fabricating high-performance perovskite solar cells. Furthermore, we found that mixed two anti-solvents, can get more driving force to let the perovskite precursor into the metastable zone. So, we can fabricate high crystal, high coverage and smooth perovskite film to make perovskite solar cell by mixed anti-solvents treatment. It can improve the fill factor of perovskite solar cell. We use TL/DCB(v/v=5/5) as anti-solvent, can let the n-i-p type perovskite solar cell toward 18.01%(AM1.5G, 100mW/cm2). On the other hand, there are the same effect of mixed anti-solvent in p-i-n type perovskite solar cell. In p-i-n perovskite solar cell, we add 0.1wt% PCBM in TL/DCB. It can fill the grain boundary in perovskite film, increase the electron collection, improve the fill factor and current density. After the optimize, the efficiency can toward 16.31% from 15.37% (AM1.5G, 100mW/cm2).
Finally, we use the optimize anti-solvent condition combine the 5cm×5cm perovskite module pattern designed by our lab(active area 10.56 cm2). For n-i-p type perovskite sub-module, the efficiency is about 14.56%(AM1.5G, 100mW/cm2). For p-i-n type perovskite sub-module, the efficiency is about 15.02%(AM1.5G, 100mW/cm2). Moreover, we use NiOx as hole transport layer instead of PEDOT:PSS, the efficiency can increase to 15.68% under AM1.5G, 100mW/cm2. | en_US |