Synthesis of Porphyrins with Novel Anchoring Groups and Extended π-conjugated Units for Highly Efficient Dye-Sensitized Solar Cells

• Main Authors: Chi-Hung Hsieh, 謝奇宏
• Other Authors: Chen-Yu Yeh
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/69cm5a

碩士 === 國立中興大學 === 化學系所 === 102 === We successfully synthesized a series of znic porphyrins H1 to H18 based on D-π-A structure. It is divided into three parts. (1) There is two phenyl groups attached at 5th, 15th-meso-positions, bearing two dodecoxyl (-OC12H25) chains at the ortho-position of each phenyl group to decrease the dye aggregation and retard the touch between electrolyte and TiO2 surface. We proposed the use of pyridine derivatives as electron -withdrawing and anchoring group in place of a conventional carboxyl group, denoted as H4, H5, H6, H7, H8, H9, H10 and H11. From the FT-IR spectra, We proposed that the bonding model between dye and TiO2 surface. We also study their absorption spectra, electrochemical properties, and photovoltaic properties. The overall efficiencies of DSSCs based on H5, H6 and H9 are all more than 8 %, and Jsc is higher than YD2-o-C8, which using the carboxy group as anchoring group in the same condition.(2) To control the distance between the porphyrin core and the anchoring group, we utilize a acenyl-ethynyl group as a bridging moiety to connect a meso position of porphyrin and the carboxylic acid end, denoted as H1, H2, H13 and H14 on the basis of YD2-o-C8 structure. But the efficiency of power conversion of these devices decreased systematically with increasing length of the link. Besides, acenes are put between porphine core and carboxylic anchoring group as the secondary chromophores in order to broaden porphyrin absorption bands, denoted as H13, H14, H15 and H17. Among those porphyrins, the benzothiadiazole -functionalized porphyrin (H17) exhibit the best performance. (3) On the basis of GY50 structure, the porphyrin sensitizers H16, H17 and H18 are designed and synthesized. The role of benzothiadiazole and bridging moiety in the structure are investigated which according to photovoltaic properties.