Acta Chim. Sinica ›› 2015, Vol. 73 ›› Issue (3): 272-280.DOI: 10.6023/A14090642 Previous Articles     Next Articles

Special Issue: 新型太阳能电池



张晓瑜, 应伟江, 武文俊, 李晶, 花建丽   

  1. 华东理工大学结构可控先进功能材料与制备实验室和精细化工研究所 上海 200237
  • 投稿日期:2014-09-14 发布日期:2014-11-03
  • 通讯作者: 李晶, 花建丽;
  • 基金资助:

    项目受国家自然科学基金(Nos. 21372082, 2116110444, 21172073, 21302055)资助.

Synthesis and Photovoltaic Performance of (Octyloxyphenyl)pyrido-[3,4-b]pyrazine-based Sensitizers for Dye-sensitized Solar Cells

Zhang Xiaoyu, Ying Weijiang, Wu Wenjun, Li Jing, Hua Jianli   

  1. Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, Shanghai 200237
  • Received:2014-09-14 Published:2014-11-03
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 21372082, 2116110444, 21172073, 21302055).

Dye-sensitized solar cell (DSSC) is one of the promising technologies for the alternative to traditional silicon- based solar cells due to its ecological and economical fabrication processes. As one of the key components of a DSSC, the sensitizers have been demonstrated to be extremely important in determining the photoelectric conversion efficiency and device stability of DSSCs. In our previous study, a series of new pyrido[3,4-b]pyrazine-based organic sensitizers (PP-I and APP-IIV) containing different donors and π-bridges have been synthesized and employed successfully in DSSCs. However, despite their remarkable stability, all of the devices exhibited quite low open-circuit voltages (Vocs), which is adverse to the solar-to-electric power conversion efficiency (η). Therefore, to address this, we have replaced the 2,3-bis(4-methoxyphenyl)pyrido[3,4-b]pyrazine (APP) with 2,3-bis-(4-(octyloxy)phenyl)pyrido[3,4-b]pyrazine (OPP). As a result, a series of new sensitizers (OPP-I) has been designed and synthesized with triphenylamine as the electron donor, OPP as the auxiliary acceptor, thiophene, furan and benzene as the π-linker, and cyanoacrylic acid as the acceptor moiety. Their optical and electrochemical properties, device performance and charge transfer kinetics were measured and studied. Compared with APP-Ⅲ, which has the highest Voc in the previous work, the Vocs of DSSCs based on OPP-I and OPP-Ⅲ have indeed been improved. Results showed that the replacement of the methoxy group with an octyloxy group can effectively reduce the π-π aggregation of the dyes on TiO2 films. Moreover, the steric hindrance of the octyloxy group successfully suppressed charge recombination and improved the open-circuit voltage. DSSCs based on OPP-Ⅲ with benzene as the π-linker have higher Voc than that of its counterparts with thiophene and furan as the π-linker, which might be ascribed to the bigger dihedral angle between benzene and OPP unit. In the end, DSSCs based on OPP-I showed the best conversion efficiency of 6.57% (Jsc=11.70 mA·cm-2, Voc=717 mV, ff=0.78) under standard global AM 1.5 solar light condition.

Key words: pyrido[3,4-b]pyrazine, octyloxybenzene, sensitizers, dye-sensitized solar cells