文献类型：期刊文献

英文题名：Hexylthiophene-Featured D-A-π-A Structural Indoline Chromophores for Coadsorbent-Free and Panchromatic Dye-Sensitized Solar Cells

作者：Wu, Yongzhen[1,2];Zhang, Xi[3,4];Li, Wenqin[1,2];Wang, Zhong-Sheng[3,4];Tian, He[1,2];Zhu, Weihong[1,2]

机构：[1]E China Univ Sci & Technol, Shanghai Key Lab Funct Mat Chem, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Inst Fine Chem, Shanghai 200237, Peoples R China;[3]Fudan Univ, Dept Chem, Shanghai 200438, Peoples R China;[4]Fudan Univ, Adv Mat Lab, Shanghai 200438, Peoples R China

年份：2012

卷号：2

期号：1

起止页码：149

外文期刊名：ADVANCED ENERGY MATERIALS

收录：;EI(收录号：20122915248341);WOS:【SCI-EXPANDED(收录号:WOS:000298982500020)】；

基金：This work was supported by NSFC/China, Major NSFC Program (90922004), National Basic Research Program of China (No. 2011CB933302, 2011CB933300), the Oriental Scholarship, SRFDP 200802510011, and the Fundamental Research Funds for the Central Universities (WK1013002). We also thank Dr. Yang Li and Baoqin Chen for useful discussion about EIS.

语种：英文

外文关键词：solar cells; sensitizers; benzothiadiazole; alkyl chains; coadsorbent-free

摘要：For a sensitizer with a strong p-conjugation system, a coadsorbent is needed to hinder dye aggregation. However, coadsorption always brings a decrease in dye coverage on the TiO2 surface. Organic DApA dyes, WS-6 and WS-11, are designed and synthesized based on the known WS-2 material for coadsorbent-free, dye-sensitized solar cells (DSSCs). Compared with the traditional DpA structure, these DApA indoline dyes, with the additional incorporated acceptor unit of benzothiadiazole in the p-conjugation, exhibit a broad photoresponse, high redox stability, and convenient energy-level tuning. The attached n-hexyl chains in both dyes are effective to suppress charge recombination, resulting in a decreased dark current and enhanced open-circuit voltage. Electrochemical impedance spectroscopy studies indicate that both the resistance for charge recombination and the electron lifetime are increased after the introduction of alkyl chains to the dye molecules. Without deoxycholic acid coadsorption, the power-conversion efficiency of WS-6 (7.76%) on a 16 mu m-thick TiO2 film device is 45% higher than that of WS-2 (5.31%) under the same conditions. The additional n-hexylthiophene in WS-11 extends the photoresponse to a panchromatic spectrum but causes a low incident photon-to-current conversion efficiency.