Acta Chim. Sinica ›› 2018, Vol. 76 ›› Issue (3): 215-223.DOI: 10.6023/A17120543 Previous Articles    

Special Issue: 纪念南开大学化学学科创建100周年



潘彬a,b, 朱义州a, 邱昌娟a, 王冰a, 郑健禺a,b   

  1. a 南开大学化学学院元素有机化学国家重点实验室 天津 300071;
    b 天津化学化工协同创新中心 天津 300071
  • 投稿日期:2017-12-17 发布日期:2018-01-22
  • 通讯作者: 朱义州, 郑健禺;
  • 基金资助:


Synthesis of Phenothiazine Dyes Featuring Benzothiadiazole Unit for Efficient Dye-sensitized Solar Cells

Pan Binaa,b, Zhu Yi-Zhoua, Qiu Changjuanaa, Wang Bingaa, Zheng Jian-Yua,b   

  1. a State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071;
    b Collaborative Innovation Center of Chemical Science and Engineering(Tianjin), Tianjin 300071
  • Received:2017-12-17 Published:2018-01-22
  • Contact: 10.6023/A17120543;
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 21572108) and Tianjin Natural Science Foundation (No. 16JCYBJC16700).

Dye-sensitized solar cells (DSSCs), as an emerging solar energy conversion technology, have attracted increasing attention for their ease of fabrication, low production cost, wide variety of dye structure, and high power conversion efficiency (PCE). As the critical component of DSSCs, photosensitizers play an important role in photon capturing, charge generation and separation, as well as electron injection at the semiconductor interface. Efforts on the design and synthesis of photosensitizers are thus an effective and straightforward way to tune the photovoltaic performance. In this article, three novel phenothiazine-based D-A-π-A type organic dyes (JY50~JY52) featuring benzothiadiazole units as auxiliary acceptors have been synthesized and applied in DSSCs. The introduction of auxiliary acceptor would take the advantages of the optimization of the dyes' energy levels and light absorption. To get more impressive device efficiency, 4-hexylbenzene group was decorated onto phenothiazine donor and has proved to be effective for improving the molar absorption coefficient and suppressing the charge recombination, finally resulting in the enhancement of photocurrent (Jsc) and photovoltage (Voc). In order to investigate the effect of different electron acceptor/anchoring group, benzoic acid and cyanoacrylic acid, which are widely applied in porphyrin-based dyes and metal-free organic dyes, respectively, are employed here to construct the target dyes. As we can see from the obtained photovoltaic performance data, dyes (JY50 and JY51) with benzoic acid anchor seem more beneficial to gain a higher Voc, this may be ascribed to its nearly vertical adsorption geometry on the TiO2 interface and the resulting decrease of the charge recombination. As for dye (JY52) with cyanoacrylic acid anchor, a better Jsc value is achieved because cyanoacrylic acid endows dye an extended conjugated system and an enhanced intramolecular charge transfer. Under AM 1.5 solar light conditions, the dye JY51 with 4-hexylbenzene unit and benzoic acid acceptor exhibited the highest PCE of 7.61%, with Voc of 797 mV and Jsc of 14.21 mA·cm-2.

Key words: phenothiazine, benzothiadiazole, organic dye, dye-sensitized solar cell, power conversion efficiency