物理化学学报 >> 2015, Vol. 31 >> Issue (10): 1977-1984.doi: 10.3866/PKU.WHXB201509075

光化学和辐射化学 上一篇    下一篇

基于苯甲酸受体的咔唑染料敏化剂的合成和光电性能

郝学良,赵金鸽,高建荣,韩亮*()   

  • 收稿日期:2015-07-13 发布日期:2015-10-10
  • 通讯作者: 韩亮 E-mail:hanliang814@163.com
  • 基金资助:
    国家自然科学基金(21406202, 21176223);浙江省自然科学基金(LY13B020012)

Synthesis and Photoelectric Properties of Carbazole Sensitizing Dyes Based on a Benzoic Acid Acceptor

Xue-Liang. HAO,Jin-Ge. ZHAO,Jian-Rong. GAO,Liang. HAN*()   

  • Received:2015-07-13 Published:2015-10-10
  • Contact: Liang. HAN E-mail:hanliang814@163.com
  • Supported by:
    the National Natural Science Foundation of China(21406202, 21176223);Natural Science Foundation of ZhejiangProvince, China(LY13B020012)

摘要:

选择N-正丁基咔唑作为电子给体,芴酮作为桥键,苯甲酸作为受体,通过桥键芴酮与给体和受体连接位置的改变,设计合成了两个咔唑染料4-(6-(N-正丁基咔唑-3-基)-9-氧-9H-芴-3-基)苯甲酸(HXL-3W)和4-(7-(N-正丁基咔唑-3-基)-9-氧-9H-芴-2-基)苯甲酸(HXL-4Z).对咔唑染料的光谱性能、电化学性能和光电转换性能进行了研究,并运用密度泛函理论(DFT)方法对其几何结构和紫外-可见光谱进行了优化计算.结果表明, HXL-4Z的吸收光谱呈现两个明显的ππ*跃迁吸收峰和一个较小的对应于分子内电荷转移的吸收峰,而HXL-3W的吸收光谱则仅呈现一个ππ*跃迁吸收峰,且摩尔吸光系数远小于HXL-4Z.可能是HXL-3W分子结构中给体和受体距离较近,张力较大,导致较差的分子平面性和分子内电荷转移.因而HXL-4Z的光吸收能力和电子注入效率较优,从而具有较好的光电转换效率(2.03%) (短路电流(JSC) = 3.88 mA·cm-2,开路电压(VOC) = 700 mV,填充因子(FF) = 0.75).

关键词: 咔唑, 染料敏化剂, 苯甲酸受体, 合成, 光电性能

Abstract:

4-(6-(N-butylcarbazole-3-yl)-9-oxo-9H-fluoren-3-yl)benzoic acid (HXL-3W) and 4-(7-(Nbutylcarbazole-3-yl)-9-oxo-9H-fluoren-2-yl)benzoic acid (HXL-4Z), were designed and synthesized through the linking position variation of the fluorenone π-bridge with the N-butylcarbazole donor and a benzoic acid acceptor. The spectra, electrochemistry and photoelectric conversion properties of these carbazole dyes were investigated and their geometric structure and UV-Vis spectra were optimized and calculated using the density functional theory (DFT) method. The results show two distinct absorption peaks, ascribed to the ππ* transition, along with a small peak corresponding to intramolecular charge transfer in the absorption spectrum of HXL-4Z. However, only one ππ* transition absorption peak is found in the spectrum of HXL-3W and its molar extinction coefficient is far smaller than that of HXL-4Z. The reason for this may be a closer distance between the donor and acceptor of HXL-3W leading to a large tension, causing inferior molecular planarity and intramolecular charge transfer. Therefore, HXL-4Z which possesses superior light absorptivity and electron injection efficiency, shows an enhanced photoelectric conversion efficiency of 2.03% (short-circuit photocurrent density (Jsc) = 3.88 mA·cm-2, open-circuit photovoltage (Voc) = 700 mV, fill factor (FF) = 0.75).

Key words: Carbazole, Sensitizing dye, Benzoic acid acceptor, Synthesis, Photoelectric property