Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (10): 1977-1984.doi: 10.3866/PKU.WHXB201509075

• PHOTOCHEMISTRY AND RADIATION CHEMISTRY • Previous Articles     Next Articles

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
  • Supported by:
    the National Natural Science Foundation of China(21406202, 21176223);Natural Science Foundation of ZhejiangProvince, China(LY13B020012)


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