臺灣博碩士論文加值系統

鈦金屬廣泛應用於航太與生醫材料，本身具有優異的耐化學腐蝕及生物相容性，在另一方面常作為可撓性染料敏化太陽能電池的軟性基材，而本研究主要利用鈦金屬基材以陽極發色處理技術(Anodizing Oxidation Coloring Technology, AOT)進行鈦的表面處理，將已經預處理的鈦金屬作為陽極電極，置於陽極發色電解液中，藉由調整不同的電壓條件，因此改變所形成的鈦氧化層厚度，而厚度大小會因受到光線干擾不同而產生折射及反射現象，呈現出多彩的鈦金屬。而本研究將經過陽極發色處理的多彩性鈦片以及染料敏化太陽能電池作兩者間的結合，透過一些儀器分析，可發現鈦氧化層的結構能夠有效抑制電子逆反應發生及具有提升電子收集效率的功用，而利用穿透式電子顯微鏡(Transmission Electron Microscopy, TEM)及電子能譜儀(X-ray Photoelectron Spectrometer, XPS)鑑定鈦氧化層的結構組成以二氧化鈦(TiO2)為主，測量鈦氧化層厚度大約為30到100 nm左右，由此可知所形成的鈦氧化層厚度會隨電壓條件越高而產生越厚的鈦氧化層，另外，以太陽光及室內光源(600及1000 lux)強度下量測電池元件性能，找出在電壓條件為10 V時，可獲得最佳的光電轉換效率，約改善20%電池光電轉換效率，在室內光源照射下也有同樣趨勢，而主要增加貢獻於JSC，最後以交流阻抗分析(Electrochemical Impedance Spectroscopy ,EIS)及強度調控光電流/光電壓譜儀(Intensity-modulated photocurrent/photovoltage spectroscopy, IMPS/IMVS)了解電池內部各部位阻抗及電子運作情形，證明鈦氧化層有效抑制逆反應以及提升電子收集功用。
而本研究另一部分是利用陽極發色處理得到的最佳參數(10 V)以大氣電漿系統搭配氧氣進行表面改質處理，主要目的為了降低鈦氧化層表層的缺陷，透過XPS分析Ti2p鍵結能計算特徵峰值線下面積，藉此可知Ti4+與Ti3+在鈦氧化層中的含量多寡，可發現經過大氣電漿處理後之鈦片基材明顯降低氧空位(oxygen vacancy)，因此大幅提升電池性能，故本研究成功結合陽極發色處理技術搭配大氣電漿表面處理以及染料敏化太陽能電池，兼具多彩鈦片的美觀且可有效提升電池光電轉換效率。

Titanium (Ti) foil is widely employed as a flexible photo-anode substrate in dye-sensitized solar cells (DSSCs). To increase the specific surface area of the Ti substrate, the Ti surface was etched to form a porous titanium dioxide (TiO2) layer through anodizing oxidation technology (AOT). The surface TiO2 film showed a high color variety with various AOT voltage which was attributable to the light refraction and scattering capability of the TiO2 structures. With the porous TiO2 structure, the electrical contact between screen-printed TiO2 nanoparticle film and the Ti substrate was improved. The porous TiO2 structure also suppressed the charge back-reaction on the photo-anode substrate based on the impedance analysis of electrochemical impedance spectroscopy (EIS). A higher power conversion efficiency (PCE) of DSSC based on the porous TiO2 structure was achieved and the contribution was mainly due to increased short- circuit current density (JSC).
It’s well known that titanium dioxide surface has been observed suboxide and oxygen vacancy such as titanium(III) oxide (Ti2O3) and titanium oxide (TiO). In order to reduce the oxygen vacancy on the TiO2 film by using the atmospheric plasma surface treatment with oxygen gas .A X-ray Photoelectron Spectrometer (XPS) results showed that plasma-treated Ti obviously reduced titanium(III) (Ti3+) concentration on the TiO2 film and improve the cells efficiency.

摘要 i
Abstract ii
目錄 iii
圖目錄 vi
表目錄 ix
第一章 緒論 1
1-1 前言 1
1-2 研究動機 3
第二章 文獻回顧 4
2-1 染料敏化太陽能電池發展歷史 4
2-2染料敏化太陽能電池簡介 5
2-2-1 染料敏化太陽能電池結構 5
2-2-2 染料敏化太陽能電池運作原理 7
2-2-3 影響效率因素 10
2-3 太陽能電池性能參數 11
2-3-1 太陽光模擬光源 11
2-3-2 量測參數與計算 11
2-4 光電極基材 13
2-4-1 玻璃基材 13
2-4-2 金屬基材 13
2-4-3 塑膠基材 17
2-5 金屬半導體氧化物 18
2-6 染料分子 19
2-7 電解液 20
2-8 對電極 21
2-9 鈦片表面處理 21
2-9-1 鈦陽極發色處理簡介 21
2-9-2 陽極處理原理 24
2-9-2 陽極處理應用於染料敏化太陽能電池 24
2-10 電漿表面處理 26
2-10-1電漿介紹 26
2-10-2電漿表面處理應用於染料敏化太陽能電池 27
第三章 實驗方法 28
3-1 實驗儀器設備與藥品 28
3-2 實驗方法與流程 30
3-2-1 鈦箔板基材前處理 30
3-2-2 陽極發色處理 30
3-2-3 大氣電漿表面處理 31
3-2-4 製備光電極 31
3-2-5 製備對電極 32
3-2-6 染料配製與浸泡方法 32
3-2-7 液態電解液配製 32
3-2-8 熱封膜 33
3-2-9 實驗流程圖 33
3-2-10 分析方法及儀器 34
3-3 分析儀器設備 34
3-3-1 太陽光之性能測量(One Sun illumination) 34
3-3-2 掃描式電子顯微鏡(Field Emission Scanning Electron Microscope, FE-SEM) 34
3-3-3 穿透式電子顯微鏡(Field Emission Transmission Electron Microscope, FE-TEM) 35
3-3-4 化學表面電子能譜儀(X-ray Photoelectron Spectroscope, XPS) 35
3-3-5 X光繞射分析儀(High Resolution X-ray Diffractometer, XRD) 35
3-3-6 原子力顯微鏡(Atomic Force Microscope, AFM) 35
3-3-7 電化學交流阻抗分析(Electrochemical Impedance Spectroscopy, EIS) 35
3-3-8 光電轉換效率量測及反射波長量測(Incident Photo-to-electron Conversion Efficiency, IPCE & Optical Reflection) 36
3-3-9 室內光源之元件性能測量(Dim light illumination) 36
第四章 結果與討論 37
PART I 37
4-1 陽極處理鈦金屬色彩 37
4-1-1 廠商陽極發色處理 38
4-1-2 實驗室自行陽極處理(30 V–90 V) 39
4-1-3 實驗室自行陽極處理(5 V–20 V) 40
4-2 陽極處理後鈦片表面形貌分析 41
4-2-1 陽極處理鈦片Top view 41
4-2-2 AFM表面粗糙度分析 47
4-3 晶型與結晶型態分析 48
4-4 陽極處理之氧化層組成分析 49
4-4-1 TEM鈦氧化層厚度&組成分析 49
4-4-2 XPS表面組成分析 51
4-5 電池元件性能量測 56
4-5-1 廠商陽極處理 56
4-5-2 太陽光與室內光源之光電性質 57
4-5-3 電化學性質分析 62
4-6 陽極處理色彩分析 66
4-6-1 表面反射率量測 66
PART II 68
4-7 陽極處理高溫退火 68
4-7-1 高溫退火溫度表面形貌 68
4-7-2 電池元件分析 70
PART III 72
4-8 大氣電漿表面處理 72
4-8-1 大氣電漿後表面形貌 72
4-8-2 XPS表面組成分析 73
4-8-3 氧化層厚度&組成分析 75
4-8-4 電池性能量測 77
4-8-5 電化學分析 80
第五章 結論 82
參考文獻 83

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