可撓式染料敏化太陽能電池(Flexible dye-sensitized solar cells, DSSCs)具備了製作成本低廉、應用範圍較廣、可大量生產等優點，因此近年來受到相當大的關注。相較於塑膠基板，金屬基板可藉由高溫燒結以促進基板與二氧化鈦光陽極的連結，進而降低介面阻抗，提升效率。然而染料敏化太陽能電池中的I-/I3-電解液傾向腐蝕不鏽鋼基板，導致電池的光伏表現下降與長效不穩定性等問題，為了改善這個問題，本研究利用非平衡磁控濺鍍系統(Unbalanced Magnetron Sputtering System)鍍著氮化鈦保護層與雙層氮化鈦/鈦保護膜於可撓式不鏽鋼基板上，研究其腐蝕抑制能力，另又製成染料敏化太陽能電池，探討氮化鈦保護層對於電池效率表現與長效穩定性之影響。
X光繞射圖譜指出單層氮化鈦薄膜無優選方向(random orientation)，雙層結構薄膜中的氮化鈦/鈦之優選方向分別為(111)與(002)；AFM量測結果指出氮化鈦薄膜與雙層結構氮化鈦薄膜表面粗糙度分別為5.58 nm與8.2 nm，兩者皆優於不鏽鋼的2.6 nm；此外，氮化鈦薄膜與雙層結構薄膜之填充因子皆為0.8，晶粒大小皆小於25nm。動態極化掃描結果顯示，藉由鍍覆氮化鈦保護層於不鏽鋼基板，可有效減少不鏽鋼基板與腐蝕介質的接觸機率，進而降低78%的腐蝕電流密度(corrosion current density)；雙層結構氮化鈦/鈦保護層更進一步降低腐蝕電流密度。由於鈦介層能阻斷貫穿整個薄膜的孔洞，因此腐蝕電流密度相較於不鏽鋼基板整整低了十倍左右。此外傳統三極式的電化學阻抗分析結果也與動態極化掃描結果一致，故證實導入氮化鈦保護層有助於提升腐蝕抑制能力。
另一方面，本研究也針對染料敏化太陽能電池的效率與長效穩定性表現進行探討。結果顯示，加入氮化鈦薄膜於不鏽鋼基板上，可抑制Fe2O3在燒結過程中生成，進而有助於提升電池的光伏表現，光電轉換效率由2.73%增加至3.53%，上升了29%。而在長效穩定性測試中發現，鍍覆氮化鈦薄膜的染料敏化太陽能電池經過1010小時的時效處裡，光電轉換效率僅下降了30%，比起不鏽鋼電池於24小時的快速衰退，證實導入氮化鈦薄膜成功提升不鏽鋼基底電池的長效穩定性。

Flexible dye-sensitized solar cells have been attracted considerable attention due to their advantage of low production cost, widely applications, and feasibility of roll to roll mass production. Compared with plastic substrate, metal foil can withstand high sintering temperature to promote the interconnection between TiO2 particles and reduce internal resistance. However, the formation of metal oxide and potential problem of metal corrosion in the iodide-based electrolytes threatens to degrade the performance and long-term stability of the metal-based DSSCs. To resolve this dilemma, we have employed unbalanced magnetron sputtering systems to prepare TiN and TiN/Ti barriers on stainless steel substrate and then assemble flexible dye-sensitized solar cells to investigate the performance and long-term stability.
XRD results shows the single-layered TiN barrier exhibits random orientation, whereas the preferred orientation of the deposited TiN is changed to (111) prefeered orientation in the bi-layer TiN/Ti specimens due to the similar atomic packing between TiN (111) and Ti (002). The surface roughness of single-layered TiN and bi-layer TiN/Ti barrier are 5.58 nm and 8.2 nm respectively. In addition, both two barriers have high packing factor of 0.8 and grain size less than 25nm. The results of potentiodynamic polarization scan and EIS indicate both TiN and TiN/Ti barriers can effectively protect the metal substrate from the corrosive medium. Introducing a Ti interlayer has been found to further decrease the corrosion current density by an order of magnitude; however, bilayer Ti/TiN layer increase the sheet resistance by 230 %
In DSCs aspect, The TiN/SS DSCs show 23% better initial performance than SS DSCs. The enhancement of Jsc was mainly due to the fact that TiN thin films provide rougher surface than bare SS substrate, leading to higher dye-loading amount. The results of EIS analysis indicate that TiN thin film can effectively reduce the resistance between TiO2 layer and photo-electrode substrate by inhibiting Fe2O3 formation during sintering process. In addition, TiN/SS DSCs perform excellent long term stability compared with SS DSCs. It was found that the cell maintained ca. 70% of overall conversion efficiency compared with their 24 h-state after 1010 hours aging.

第一章 緒論 1
1.1前言 1
1.2太陽能電池 1
1.3太陽能電池的種類 2
1.4研究動機 3
第二章 文獻回顧 6
2.1染料敏化太陽能電池(DSCs) 6
2.1.1染料敏化太陽能電池工作原理 6
2.1.2染料敏化太陽能電池光伏特性 8
2.1.3染料敏化太陽能電池基本元件 9
2.2可撓式染料敏化太陽能電池 12
2.3不鏽鋼金屬基板光陽極 13
2.4不鏽鋼金屬基板之穩定性 14
2.5非平衡磁控濺鍍系統(Unbalanced Magnetron Sputtering System) 15
2.6氮化鈦(titanium nitride) 16
2.6.1氮化鈦基本性質 16
2.6.2 氮化鈦應用於染料敏化太陽能電池 17
第三章 實驗流程與儀器 26
3.1氮化鈦奈米薄膜製備 26
3.1.1不鏽鋼試片製備 26
3.1.2磁控濺鍍氮化鈦(TiN)奈米薄膜 26
3.2染料敏化太陽能電池的製備 27
3.2.1二氧化鈦(TiO2)光陽極漿料製備 27
3.2.2 液態電解液製備 28
3.2.3 鉑(platinum)對電極製備 28
3.2.4 染料敏化太陽能電池光陽極製備 29
3.2.5 染料敏化太陽能電池元件組裝 30
3.3分析儀器 30
3.3.1 X光繞射儀(X-ray Diffractometer) 30
3.3.2原子力顯微鏡(Atomic Force Microscopy) 31
3.3.3表面輪廓機(Alpha-Step Surface Profiler) 32
3.3.4聚焦離子束與電子束顯微鏡系統(Dual beam (focused ion beam & electron beam) System (FIB/SEM)) 32
3.3.5飛行時間二次質譜儀(Time-of-Flight Secondary Ion Mass Spectrometer) 32
3.3.6紫外光可見光光譜儀(Ultraviolet-visible Spectrophotometer) 33
3.3.7動態極化掃描(Potentiodynamic Polarization Scan) 33
3.3.8入射單色光-電子轉換效率(monochromatic incident photon-to-electron conversion efficiency) 34
3.3.9太陽光模擬器(Solar simulator) 34
3.3.10電化學阻抗分析儀(Electrochemical impedance spectroscopy) 35
第四章 結果與討論 44
4.1氮化鈦薄膜性質結果與討論 44
4.1.1氮化鈦薄膜的性質與結構 44
4.1.2氮化鈦薄膜電化學特性 46
4.2染料敏化太陽能電池之效率與長效性 59
4.2.1染料敏化太陽能電池初始狀態之結果 59
4.2.2染料敏化太陽能電池初始狀態之綜合討論 64
4.3染料敏化太陽能電池長效性探討 75
4.3.1電流-電壓光伏曲線 75
4.3.2長效性之IPCE結果 76
4.3.3長效性之電化學阻抗分析 77
4.3.4 電池長效性整體表現 78
第五章 結論 90

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