Acta Phys. -Chim. Sin. ›› 1996, Vol. 12 ›› Issue (05): 413-417.doi: 10.3866/PKU.WHXB19960506

• ARTICLE • Previous Articles     Next Articles

Time-Resolved Fluorescence Lnvestigations of Aggregation in LB Films

Lu Xing-Ze,Ma Shi-Hong,Song Jie,Han Kui,Zheng Jia-Biao,Wang Wen-Cheng   

  1. State Key Joint Laboratory for Materials Modification by Laser,Ion and Electro Beams,Physics Department,Fudan University,Shanghai 200433
  • Received:1995-09-11 Revised:1995-12-18 Published:1996-05-15
  • Contact: Lu Xing-Ze

Abstract:

 The aggregation behavior of phenylhydrazone (PD) and hemicyanine (DAEP),in Z-type LB multilayers has been studied by absorption, steady state and time-resolved fluorescence spectroscopies. The LB multilayers of pure PD and DAEP showed J-and H-aggregate formations, characterized by a large red-shift (398nm→440nm, △E-2398cm-1 )and blue-shift (510nm→465nm, △E- 1898cm-1 ), respectively. The main fluorescence emission bands were found to be at 560 nm and 584 nm for PD and DAEP multilayers. The fluorescence decay profiles of PD and DAEP in LB films could be best-fitted by using a bi-exponential decay model. Our results reveal that there mainly exist two species (monomer and dimer) in the LB multilayers with characteristic fluorescence decay time in the order of ns and 10 ps, respectively.

Key words: Langmuir-Blodgett films, aggregation, time-resolved fluorescence, phenylhydrazone, hemicyanine