在鈣鈦礦太陽能電池 (Perovskite solar cell, PSC)中，由於FTO玻璃與電洞傳輸材料(Hole transport material, HTM)間為歐姆接觸(Ohmic comtact)。一旦兩者接觸會就會造成嚴重的載子複合，降低元件光電轉換效率。因此在FTO玻璃和二氧化鈦多孔支架層中間製作一層阻隔層，避免FTO玻璃與HTM直接接觸面積並形成蕭基界面(Schotty contact)，抑制逆向電子傳輸，此為製備高效能鈣鈦礦太陽能電池的必要條件之一。
本研究使用陽極定電流沉積法製備薄且緻密的二氧化鈦(TiO2)阻隔層，藉由調控沉積的電流及電量密度來控制TiO2薄膜的形貌與厚度，並探討阻隔層之材料特性與製備條件對鈣鈦礦電池元件光電化學特性的影響。紫外光可見光光譜顯示TiO2薄膜在製備前後幾乎不影響FTO玻璃的穿透度，顯示薄膜是均勻且非常薄的形態；由場發式電子顯微鏡(FESEM)觀察發現，沉積電流密度會影響二氧化鈦薄膜的微結構；以低電流密度進行沉積時，可得到片狀排列的結晶，提高電流密度後則得到顆粒堆疊的結構。此超薄的TiO2薄膜以二次飛行質譜儀(TOF-SIMS)及循環伏安法(CV)檢測後得知，即使TiO2阻隔層的厚度低於30nm但其依舊表現出良好的抑制再結合效果，證實了電沉積TiO2阻隔層具有薄又緻密的優勢。
目前的實驗結果顯示，最適化電沉積阻隔層條件為電流密度20μA/cm2，且電量密度10mC/cm2時，厚度為13.5奈米。循環伏安檢測中發現，相較於常用的旋轉塗佈法，電沉積TiO2阻隔層的薄膜孔隙度約為旋轉塗佈阻隔層的0.7倍，且搭配電沉積阻隔層的最佳元件效率為13.6%，明顯高於旋轉塗佈法之阻隔層元件效率的10.4%。其主要改進在短路電流(JSC)與填充因子(FF)部分，顯示電沉積阻隔層的緻密性能有效抑制FTO界面的再結合反應，提升電子收集效率。

In perovskite solar cells (PSC), the fluorine-doped tin oxide (FTO) glass and hole transport material (HTM) form ohmic contacts, which lead to recombination of charge carriers and consequently reducing the cell performance seriously. The recombination is effectively reduced via introducing a blocking layer (BL) between FTO glass and titanium dioxide (TiO2) mesoporous layer, which eliminates the contact between FTO and HTM, and results in suppressing the recombination between electrons in FTO and holes in HTM. Therefore, preventing the recombination from direct contact between FTO and HTM layer is crucial for high efficiency PSC.
In this study, an ultra-thin and compact TiO2 BL on FTO glass was prepared by galvanostatic anodic deposition. This electrodeposition (ED) method can control the morphologies and thicknesses of TiO2 film by manipulating the current density and coulomb density. The material properties of BLs preparimg by various deposition conditions and their photoelectrochemical performances were also scrutinized.
Ultraviolet -Visible Spectrometer (UV-Vis) spectra show that the transmittance of FTO substrate is not affected by the ED-BL. FESEM (Field emission scanning electron microscope) images reveal that the structure of the TiO2 film is affected by the depositing current density. As the current density increases, the particle size became smaller. Evidenced by TOF-SIMS (Time-of-flight secondary ion mass spectrometer) and CV (Cyclic voltammogram), it is proved that the interfacial recombination is profoundly suppressed by ED-BL.
Comparing to the commonly used spin coating (SC) method to deposit BL, our study shows that the high quality BL can effectively enhance the performance of perovskite solar cell especially at short circuit current density JSC (mA/cm2) and fill factor FF via decreasing the electrons loss from FTO glass to HTM effectively. As a result, current collection efficiency was enhanced at FTO electrode. The best perovskite cell with ED-BL achieved a higher power conversion efficiency of 13.6% that is higher than SC-BL one of 10.4% by approximately 30%.

摘要 i
Abstract II
總目錄 IV
表目錄 VII
圖目錄 VIII
第一章 緒論 1
1-1 前言 1
第二章 文獻回顧 6
2-1 鈣鈦礦太陽能電池 (Perovskite solar cell, PSC) 6
2-1.1 鈣鈦礦太陽能電池的起源與發展歷程 6
2-1.2 鈣鈦礦太陽能電池結構與工作原理介紹 8
2-2 光陽極基板上阻隔層的製備方式與檢測 11
2-2.1 熱噴霧裂解法(Spray pyrolysis, SP) 11
2-2.2 旋轉塗佈法(Spin coating, SC) 13
2-2.3 電化學沉積法(Electrodeposition, ED) 15
2-2.4 原子層沉積法(Atomic layer deposiyion, ALD) 19
2-2.5 評斷阻隔層性能之工具以及各種阻隔層性能之綜合比較 21
2-3 研究動機與目的 26
第三章 實驗方法與儀器分析 27
3-1 實驗藥品與材料 27
3-1.1 藥品與材料簡介 27
3-1.2 藥品製備與配製 29
3-2 實驗儀器 30
3-2.1 實驗儀器與設備 30
3-2.2 操作與分析儀器簡介 31
3-3 實驗方法 41
3-3.1 電沉積TiO2薄膜 41
3-3.1.1 TiCl3電沉積之溶液配製 41
3-3.1.2 電沉積系統 41
3-3.1.3 陽極定電流沉積 42
3-3.2 鈣鈦礦太陽光電池元件製備流程 42
3-4 理論與分析原理 44
3-4.1 半導體能隙 (Band gap)量測分析 44
3-4.2 法拉第電解定律介紹 45
3-4.3 循環伏安法原理介紹 46
3-4.4 Mott-Schottky 原理介紹 49
第四章 結果與討論 51
4-1 TIO2電沉積反應討論與分析 51
4-2 電沉積TIO2阻隔層材料分析 53
4-2.1 TiO2薄膜結晶型態分析 53
4-2.2 TiO2薄膜能隙量測 55
4-3 改變沉積電流密度對阻隔層特性之分析 55
4-3.1 TiO2阻隔層表面形貌分析 55
4-3.2 沉積TiO2阻隔層於玻璃基板之光學性質探討 56
4-3.3 TiO2阻隔層之循環伏安法分析 57
4-3.4 TiO2阻隔層之鈣鈦礦光伏元件效能表現 62
4-4 不同沉積電量密度阻隔層特性分析 65
4-4.1 電沉積TiO2阻隔層於FTO玻璃表面的形貌分析 65
4-4.2 電沉積TiO2阻隔層於玻璃基板之光學性質探討 66
4-4.3 TiO2阻隔層厚度分析 67
4-4.4 TiO2阻隔層之循環伏安法分析 70
4-4.5 TiO2阻隔層之鈣鈦礦光伏元件效能表現 72
4-5 最適化電沉積與旋轉塗佈之阻隔層比較 74
4-5.1 TiO2阻隔層於FTO玻璃表面的形貌分析 74
4-5.2 TiO2阻隔層於玻璃基板之光學性質探討 76
4-5.3 TiO2阻隔層之循環伏安法分析 77
4-5.4 TiO2阻隔層之Mott-schottky分析 79
4-5.5 TiO2阻隔層之鈣鈦礦光伏元件效能表現 81
第五章 結論與未來展望 83
5-1. 結論 84
5-2. 未來展望 85
第六章 參考文獻 86
附錄A 90

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