### 应用于染料敏化太阳能电池的基于染料R6的含有不同吸电子基团的有机染料的理论研究

• 收稿日期:2019-05-30 录用日期:2019-07-25 发布日期:2019-07-31
• 通讯作者: 李敏杰,陆文聪 E-mail:minjieli@shu.edu.cn;wclu@shu.edu.cn
• 基金资助:
国家科技部“十三五”科技计划(2016YFB0700504);上海市自然科学基金(16ZR1411500);上海市科学技术委员会(18520723500)

### Theoretical Study of High-Efficiency Organic Dyes with Different Electron-Withdrawing Groups Based on R6 toward Dye-Sensitized Solar Cells

Zhen Wei, Minjie Li(), Wencong Lu()

• Received:2019-05-30 Accepted:2019-07-25 Published:2019-07-31
• Contact: Minjie Li,Wencong Lu E-mail:minjieli@shu.edu.cn;wclu@shu.edu.cn
• About author:Email: wclu@shu.edu.cn (W.L.); Tel.: +86-21-66133513 (W.L.)
Email: minjieli@shu.edu.cn (M.L.); Tel.: +86-21-66133513 (M.L.)
• Supported by:
the National Key Research and Development Program of China(2016YFB0700504);Natural Science Foundation of Shanghai, China(16ZR1411500);Science and Technology Commission of Shanghai Municipality, China(18520723500)

Abstract:

Dye-sensitized solar cells (DSSCs) are the most promising alternatives to traditional fossil energy because of their advantages of low production cost, facile structure, relatively low environmental impact, relatively high photoelectronic absorption efficiency, and overall high efficiency. In addition, several studies on sensitizers as vital components have been conducted over the last three decades. Compared to metal dyes, metal-free organic dyes have been considered as promising candidates because of their simple fabrication, multiple structures, high molar absorption coefficients, easily tunable properties, and environmental friendliness. In this study, we systematically investigated the optoelectronic properties of six metal-free organic donor-acceptor dyes (RD1–6) derived from the known dye R6 by using the density functional theory (DFT) and time-dependent DFT methods. Cell performance parameters were discussed, including the geometrical and electronic structures, absorption spectrum, adsorption energy, light harvesting efficiency (LHE) curve, predictive short circuit current density (JscPred.), predictive open circuit voltage (VocPred.), and theoretical power conversion efficiency (PCE). Results revealed that all the designed dyes exhibited high theoretical PCE. In particular, dyes RD1, 2, and 4–6 showed greater conjugations, and dyes RD1–3 had smaller energy gaps than those of the reference dye. In addition, dyes RD1–3, 5, and 6 exhibited better light harvesting capacities that covered the entire visible region and extended to the near-infrared region with obviously red-shift maximum absorption wavelengths (λmax), wider LHE curves, and higher JscPred. as compared to the reference dye. It was critical that dyes RD1 and 2 not only have greater conjugations and narrow band gaps but also good light harvesting capacities with more than 56-nm red-shift maximum absorption wavelengths and broadened LHE curves than those of the reference dye. Notably, mainly because of an average increment of 12.0% of JscPred., a remarkable increment of the theoretical power conversion efficiency was observed from 12.6% for dye R6 to 14.1% for dyes RD1 and 2. Thus, dyes RD1 and 2 exhibited superior cell performances and could be promising sensitizer candidates for highly efficient DSSCs. These results could be used to guide effective synthetic efforts in the discovery of efficient metal-free organic dye sensitizers in DSSCs.

MSC2000:

• O641