環修飾之紫質的設計與合成以應用於太陽能光敏染 Design and Synthesis of Core-modified Porphyrin Sensitizers for Dye-Sensitized Solar Cells

dc.contributor 洪政雄 zh_TW
dc.contributor Chen-Hsiung Hung en_US
dc.contributor.author 山地普 zh_TW
dc.contributor.author Sandeep Mane en_US
dc.date.accessioned 2019-09-04T10:31:52Z
dc.date.available 2019-6-17
dc.date.available 2019-09-04T10:31:52Z
dc.date.issued 2014
dc.description.abstract 此篇論文報導了新的環修飾紫質以及大環紫質的設計與合成,以及其在太陽能光敏染料之應用。此些染料的發展由單硫取代紫質以及單氧取代紫質開始,並且其上有一ethynylphenyl 基團為共振鏈以及以羧基為掛載基團。比較這些異原子取代紫質與傳統的四氮紫質,結果顯示異原子的取代降低了這些染料的光電伏打效率,其中單氧取代的紫質表現更低於單硫取代的紫質。接著我們對單硫取代紫質進行了環修飾得到了擁有A3B以及A2B2之不同取代型式的五種衍生物。經由光物理和電化學的研究顯示以ethynylphenyl基團延伸共振的鏈長不僅增加了環的平面性,同時也增加了光譜的紅位移。而在取代基上加上擁有拉電子能力的cyano基團亦可增加分子的極性而讓分子有較佳的電荷轉移效果。結合上訴修飾,單硫取代紫質的光電轉換效率可由沒有cyano基團的0.2 % 提升到有cyano基團的1.69 %。 我們亦致力於研究大環紫質於太陽能光敏染料的應用。我們合成出了有硼配位的oxasmaragdyrins,其是擁有22 個π電子共振的芳香大環紫質。這些染料擁有合適的還原電位,高消光係數,良好的穩定性,以及高光電轉換效率。更重要的,其在可見光區段的吸光範圍廣泛,且其較低能量的Q band吸收位於在紅外光區段。基於上述條件,oxasmaragdyrins適合用來發展為太陽能光敏染料。我們亦於了oxasmaragdyrins 環上掛載了不同的推拉電子基,並進行研究與討論。令人意外的,掛載上tripheylamine為推電子基以及ethynylphenyl為共振鏈的染料其光電轉換效能相較於未修飾的染料並未增加。 最後,我們合成了分別擁有一個和兩個羧基的新的二氮三硫 sapphyrins化合物並且將其應用於太陽能光敏染料。由電化學研究看來,其最低未佔軌域與二氧化鈦之傳導能帶間的差距太相近,使其不夠能讓激發的電子做有效的電子注入至二氧化鈦,故此染料的光電轉換效率不佳。 至目前為止,此論文完成了單硫取代紫質最高的光電轉換效率,並且開發出了一系列新的大環紫質為高效率的太陽能光敏染料。 zh_TW
dc.description.abstract This thesis reported the design and synthesis of novel core-modified and expanded porphyrin sensitizers for dye-sensitized solar cells. The development of these sensitizers starts off with novel thiaporphyrin and oxaporphyrin, which consists of ethynylphenyl group as a conjugated linker and carboxylic acid as anchoring group. Comparative photovoltaic studies of these heteroporphyrins with regular N4 porphyrins show that core-modification results in decreased performance, with moderate efficiency for thiaporphyrin and minute efficiency for oxaporphyrin. Following parts of this thesis regard the development strategy through core-modification. The periphery of thiaporphyrin was modified to obtain five more derivatives with A3B and A2B2 substitution pattern. The photophysical and electrochemical studies revealed that the π-extension through the ethynylphenyl group not only made the macrocycle planar but also increased their absorption bathochromicaly. Furthermore, substitution of the electron withdrawing cyano group produced higher polarizability required for the effective charge transfer from the porphyrin ring to the anchoring cyanoacrylic group. All these factors contributed to achieve the highest overall power conversion efficiency of 1.69% for N3S-ECN compared to other thiaporphyrin dyes. We also devote effort to uncover the potential of applying expanded porphyrins to DSSC studies. Boron chelated oxasmaragdyrins, a class of aromatic core-modified expanded porphyrin with a 22 π-electron conjugation were synthesized. These dyes provided desired redox potentials, high absorption coefficients, high stability, and higher power conversion efficiencies. More importantly, broad absorption spreading over the entire visible region and its lower energy Q bands covering part of the NIR region. The factor above made this class of compound an optimistic candidate for being one of the future selections of porphyrin-sensitized solar cells. The molecular engineering of these oxasmaragdyrins through peripheral substitution with various donors and acceptors was also discussed. To our surprise, utilizing of triphenylamine unit as a donor and ethynylphenyl group as a linker did not improve the overall performance for these dyes. Finally, novel mono or dual carboxylate functionalized N2S3 sapphyrins were prepared and applied as sensitizers in DSSCs for the first time. From the electrochemical studies it was observed that, the potential difference between the LUMO level of the dyes and conduction band of TiO2 was not sufficient for effective electron injection, which ultimately resulted in minute power conversion efficiencies for this class of dyes. In an effort to enhance the overall performance of porphyrin dyes, we also evaluated the co-sensitization effect. We combined two discretely moderate dyes, a free-base porphyrin and its zinc derivative, with complementary absorption spectra to construct a mixed porphyrin DSSC. From photo-action spectra, it is evident that the incident photon collection for the mixed dyes is higher than both the individual dyes due to the broader absorption. For the Mix-1, consisting of N4CA (2.71%) and N4ZnCA (3.09%), we observed conversion efficiency of 3.28% which higher than both the individual dyes, while for Mix-2, comprising for N4CN (1.94%) and N4ZnCN (3.52%), overall photon-to-current conversion efficiency of 4.18% was observed. We also evaluated the effectiveness of oxadiazole group as electron transporter. We attached an electron donor, oxadiazole ring and phenyl or thiophenephenyl group as linkers and carboxylic or cyanoacrylic group as anchor in D-π-A fashion to prepare three novel OD dyes. Although, the optical and electrochemical properties and DFT calculations confirmed good absorption features and effective charge separation, only moderate efficiency of 2.72% was observed for OD3 dye. So far, the work from this thesis has led to achieve the highest efficiency for thiaporphyrins and also unleashed a new class of porphyrinoids, the expanded porphyrins as highly efficient sensitizers for DSSCs. en_US
dc.description.sponsorship 化學系 zh_TW
dc.identifier GN0898420121
dc.identifier.uri http://etds.lib.ntnu.edu.tw/cgi-bin/gs32/gsweb.cgi?o=dstdcdr&s=id=%22GN0898420121%22.&%22.id.&
dc.identifier.uri http://rportal.lib.ntnu.edu.tw:80/handle/20.500.12235/101076
dc.language 英文
dc.subject 太陽能光敏染料 zh_TW
dc.subject 環修飾紫質 zh_TW
dc.subject 大環紫質 zh_TW
dc.subject 硼配位的oxasmaragdyrins zh_TW
dc.subject Dye-sensitized solar cells en_US
dc.subject core-modified porphyrins en_US
dc.subject expanded porphyrins en_US
dc.subject organic dyes en_US
dc.title 環修飾之紫質的設計與合成以應用於太陽能光敏染 zh_TW
dc.title Design and Synthesis of Core-modified Porphyrin Sensitizers for Dye-Sensitized Solar Cells en_US
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