中国物理B ›› 2009, Vol. 18 ›› Issue (4): 1622-1626.doi: 10.1088/1674-1056/18/4/056

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Conductance switching mechanism of Rose Bengal organic thin films in ambient conditions

蔡莉, 郭海明, 朱熙, 杜世萱, 时东霞, 高鸿钧   

  1. Institute of Physics, the Chinese Academy of Sciences, Beijing 100190, China
  • 收稿日期:2008-07-28 修回日期:2008-08-25 出版日期:2009-04-20 发布日期:2009-04-20
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos 60771037 and 10774176) and the National High Technology Research and Development Program of China (Grant No 2006CB921305).

Conductance switching mechanism of Rose Bengal organic thin films in ambient conditions

Cai Li(蔡莉), Guo Hai-Ming(郭海明), Zhu Xi(朱熙), Du Shi-Xuan(杜世萱), Shi Dong-Xia(时东霞), and Gao Hong-Jun(高鸿钧)   

  1. Institute of Physics, the Chinese Academy of Sciences, Beijing 100190, China
  • Received:2008-07-28 Revised:2008-08-25 Online:2009-04-20 Published:2009-04-20
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos 60771037 and 10774176) and the National High Technology Research and Development Program of China (Grant No 2006CB921305).

摘要: The molecular thin films of Rose Bengal (RB) embedded in polymethyl methacrylate matrix are fabricated by using the spin-coating technique. The macroscopic current--voltage (I--V) characterization of the film shows that the RB molecule has two conductance switching states with a high ON/OFF ratio in ambient conditions. The infrared spectra indicate that intermolecular hydrogen bonds can form in the RB thin films after their hydrolysis in air. With the first-principles calculations, we demonstrate that the hydrogen bonds will be destroyed in concomitance with the conformational change when the RB molecule switches to its high-conductance state after applying a voltage.

Abstract: The molecular thin films of Rose Bengal (RB) embedded in polymethyl methacrylate matrix are fabricated by using the spin-coating technique. The macroscopic current--voltage (I--V) characterization of the film shows that the RB molecule has two conductance switching states with a high ON/OFF ratio in ambient conditions. The infrared spectra indicate that intermolecular hydrogen bonds can form in the RB thin films after their hydrolysis in air. With the first-principles calculations, we demonstrate that the hydrogen bonds will be destroyed in concomitance with the conformational change when the RB molecule switches to its high-conductance state after applying a voltage.

Key words: Rose Bengal, conductance transition, mechanism

中图分类号:  (Thin film structure and morphology)

  • 68.55.-a
61.41.+e (Polymers, elastomers, and plastics) 68.37.Ps (Atomic force microscopy (AFM)) 85.60.-q (Optoelectronic devices) 78.30.Jw (Organic compounds, polymers)