Acta Chimica Sinica ›› 2009, Vol. 67 ›› Issue (24): 2779-2784. Previous Articles     Next Articles

Special Topic

基于过渡金属离子与三联吡啶的配位作用构筑全共轭层-层
自组装超薄功能膜

潘月秀1,佟斌1,支俊格1,赵玮1,申进波1,石建兵1,董宇平2   

  1. 1. 北京理工大学
    2. 北京理工大学材料科学与工程学院
  • 投稿日期:2009-04-30 修回日期:2009-06-15 发布日期:2010-02-04
  • 通讯作者: 董宇平 E-mail:chdongyp@bit.edu.cn

Full-conjugated Layer-by-Layer self-assembly Ultrathin Functional Films Fabricted from Terpyridine and Transition Metal Ions based on Coordinate Interaction

Pan Yue-Xiu1, 1, 1, 1, 1, 1,   

  • Received:2009-04-30 Revised:2009-06-15 Published:2010-02-04

A novel conjugated light-sensitive diazonium-containing compound, 4'-(2,2':6',2''-terpyridyl) benzenediazonium tetrafluoroborate (Diazo-tpy) was firstly synthesized and used to modify substrate by electrostatic interaction. Following the decomposition of diazonium group of Diazo-tpy under UV irradia-tion, the ionic bonds between the diazonium salt and substrate are converted to the covalent bonds. The ter-pyridine-containing monolayer film anchoring on the substrate is very stable. Specially, the π-conjugated system of the terpyridinyl groups is linked to the surface of the substrate, which can greatly facilitate the transport of charges between them. Furthermore, the layer-by-layer (LBL) self-assembled (SA) films of 4'?4'''-(1,4-phenyl)-bis(2,2':6',2''-terpyridine) (Bi-tpy) and different transition metal ions (Pt4+、Ru3+、Rh3+、Pd2+) were fabricated on the tpy-modified substrate, and were well characterized using UV-vis absorption spectroscopy. The UV-vis analytic results indicate that the LBL Bi-tpy/Mtn+ SA multilayer films, having axial ligand between metal atom and terpyridyl group, have been successfully fabricated and a pro-gressive assembly runs regularly with almost equal amount of deposition in each cycle. Under illumination, the SA films on ITO shows an effective photoinduced charge transfer and changed the current density of the ITO. The result revealed that the photoelectric conversion property of Bi-tpy/Ru film is higher than that of Bi-tpy/Pt film. With an increase in the layer number, the photocurrent rises and reaches its maximum at 6 bilayers. Further increment leads to a current drop due to the increase in probability of objection and the cell resistance. The results allow us to design new materials for more optoelectronic applications.

Key words: terpyridine, transition metal ion, layer-by-layer self-assembly, coordinate interaction, photoelectric property