Carbon nanotube-incoporated photoanode and its electrochemical properties for dye-sensitized solar cells
黃仲翊、姚品全
E-mail: [email protected]
ABSTRACT
This study divided into two parts, the first part to look at a variety of (LiI, NaI, KI) and Propylene carbonate (PC) the composition of the electrolyte system to AC impedance method (AC Impedance), etc. Characteristics of electrochemical; as a dye-sensitized solar cells (Dye-Sensitized Solar Cell, DSSC) electrolyte systems, measurement of its Photoelectric conversion efficiency on a variety of electrolyte systems for the photovoltaic characteristics of the impact of components. The second part of this study was primarily aimed at the working electrode, in order to spin a good TiO2 coating solution will be allocated to the ITO coated glass as working electrode after sintering, and with different thickness, to observe the heterogeneous structure of the photoelectric conversion
efficiency. Electrolytes are EKM-034 (0.34 M KI +0.01 M I2 in PC), ENM-034 (0.34 M NaI +0.01 M I2 in PC), ELM-034 (0.34 M LiI +0.01 M I2 in PC) to observe the performance of its IV. The results showed that TiO2 film with the working electrode is directly proportional to the number of spin-coating, and when the working electrode thickness reached at 9.1μm (six), with the best of the photoelectric conversion efficiency, when it increased again when the electrode thickness, light no further increase in power conversion efficiency, but slightly short-circuit current. Based on the above conclusions, the best known of these study process parameters: TiO2 layer six, electrolyte is ELM-034, may be the largest photovoltaic conversion efficiency, η = 6.33 %, PV test results are: VOC = 0.730 V, JSC = 15.36 mA, FF = 56.46 %. Heterogeneous structure can futher uprade photovoltaic conversion efficiency, The structure of ITO / P25-TiO2 (6L) / CNT, PV test results are as follows; VOC = 0.690 V, JSC = 18.44 mA, FF = 53.60 %, η = 6.82 %; the structure of ITO / Sol-Gel TiO2 (3L) / P25-TiO2 (6L) / CNT, PV test results are as follows; VOC = 0.657 V, JSC = 18.06 mA, FF = 55.26 %, η = 6.56 %; the structure of ITO / SnO2 / Sol-Gel TiO2 (3L) / P25-TiO2 (6L) / CNT, PV test results are as follows; VOC = 0.663 V, JSC = 19.15 mA, FF = 55.40 %, η = 7.03 %. It can be seen: The carbon
nanotube-modified working electrode of titanium dioxide, contribute to dye-sensitized solar photovoltaic conversion efficiency.
AC Impedance analysis and PV measurement shows: PC solvent system, electrolyte Composition its size LiI > NaI > KI.
Keywords : Dye-Sensitized Solar Cell、AC Impedance、electrolyte、carbon nanotubes Table of Contents
封面內頁 簽名頁 授權書...iii 中文摘要...iv ABSTRACT...vi 誌謝...viii 目
錄...ix 圖目錄...xiii 表目 錄...xvi 第一章 緒論...1 1.1 前 言...1 1.2 太陽能電池簡介...2 1.3 研究動
機...4 1.4 本文架構...6 第二章 文獻回顧與理論原 理...7 2.1 有機太陽電池簡介...7 2.2 染料敏化太陽能電池之工作原 理...9 2.3 染料敏化太陽能電池組成簡介...12 2.3.1 TiO2工作電
極...12 2.3.2 染料...14 2.3.3 電解
質...16 2.3.4 對電極...18 2.3.5 太陽光譜簡
介...18 2.4 DSSC之交流阻抗等效電路...21 2.5 染料敏化太陽能電池之供 電原理...23 2.6 染料敏化太陽能電池之等效電路...26 2.7 染料敏化太陽能電池之光 電轉換特性...28 2.7.1 短路電流( Isc，short circuit current )...28 2.7.2 開路電壓 ( Voc，open circuit voltage )...29 2.7.3 填充因子 ( FF，fill factor )...29 2.7.4 能量轉換效率 ( η，power conversion efficiency )...30 2.8 染料敏化太陽能電池之串聯電阻...32 第三章 實驗設備與方 法...35 3.1 實驗藥品及材料...35 3.2 實驗儀
器...36 3.2.1 燒結系統...36 3.2.2 濺鍍
機(Sputter)...37 3.2.3 濃縮系統(Enrichment system)...37 3.3 量測設
備...38 3.3.1 冷場發射型掃描式電子顯微鏡(FE-SEM)...38 3.3.2 太陽光模擬器 與IV量測儀器...39 3.3.3 紫外/可見光分光光譜儀(UV/VIS)...40 3.3.4 恆電位
儀...41 3.4 實驗方法...42 3.4.1 實驗流
程...42 3.4.2 氧化銦錫玻璃(ITO)基板之清洗...44 3.4.3 電解液配 置...45 3.4.4 染料配製...46 3.4.5 鍍膜液之製
作...46 3.4.6 工作電極之製作...48 3.4.7 Pt對電極製 作...49 3.4.8 組裝及電解液注入...49 第四章 結果與討 論...51 4.1 工作電極製備SEM之膜厚分析...51 4.2 UV/VIS分 析...54 4.2.1 D719染料於D.I Water溶劑分析[36]...54 4.3光電量測部
份...56 4.3.1 PEG分子量於TiO2之影響...56 4.3.2 電解質組成對光伏特性 之影響：不同濃度影響...57 4.3.3 工作電極的膜厚對光伏特性之影響...59 4.3.4 電解質組成對 光伏特性之影響：陽離子的影響...60 4.3.5 添加奈米碳管比例對光伏特性之影響...61 4.4 新穎 電極結構...64 4.4.1 SG-TiO2工作電極的層數對光伏特性之影響...64 4.4.2 階層結 構工作電極對光伏特性之影響...66 4.4.3 奈米碳管修式P25-TiO2對光伏特性之影響...69 4.4.4 奈米碳管修式SG-TiO2對光伏特性之影響...70 4.4.5 添加奈米碳管修式SnO2對光伏特性之影 響...72 4.5 電化學-交流阻抗分析...73 4.5.1 工作電極的膜厚之交流阻抗分 析...73 4.5.2 電解質組成之交流阻抗分析：陽離子的影響...75 4.5.3 奈米碳管修
式P25-TiO2之交流阻抗分析...76 4.5.4 奈米碳管修式SG-TiO2之交流阻抗分析...77 4.5.5 加 奈米碳管修式SnO2之交流阻抗分析...78 第五章 結論...80 參考文
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