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  

Full-conjugated Layer-by-layer Self-assembly Ultrathin Functional Films Fabricated from Terpyridine and Transition Metal Ions Based on Coordinate Interaction

作　　者：潘月秀[1] 佟斌[1] 支俊格[2] 赵玮[1] 申进波[1] 石建兵[1] 董宇平[1] 

机构地区：[1]北京理工大学材料科学与工程学院,北京100081 [2]北京理工大学理学院,北京100081

出　　处：《化学学报》2009年第24期2779-2784,共6页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.50573008;20634020);教育部博士点专项基金(No.20050007018)资助项目

摘　　要：利用所合成的4-(2,2':6',2''-三联吡啶-4'-基)苯重氮氟硼酸盐(Diazo-tpy)在紫外光照射下的光分解反应特性,实现三联吡啶基团与基片之间形成共轭价键连接,这不仅提高了自组装膜的稳定性,而且降低了载流子在两者之间传输时的阻抗;在此基础上,通过两端含三联吡啶的直线型配体1,4-二(2,2':6',2''-三联吡啶-4'-基)苯(Bi-tpy)与四种过渡金属离子(Mn++:Pt4++,Ru3++,Rh3++,Pd2++)之间的配位作用,通过层-层自组装制备了全共轭金属-有机自组装超薄功能膜.由紫外-可见光谱跟踪自组装过程证明了自组装过程的成功实现,还分析了金属离子的种类对自组装的影响规律.光电转换测试表明Bi-tpy/Ru3++自组装膜要比Bi-tpy/Pt4++具有更明显的光电转换性能;同时,由于缺陷与阻抗随层数的增加而增大的原因,在自组装6层时光电流达到最大值.这为我们设计新型光电转换器件提供参考依据.A novel conjugated light-sensitive diazonium-containing compound, 4-（2,2＇：6＇,2＇＇-terpyrid-4＇-yl） 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 irradiation, the ionic bonds between the diazonium salt and substrate were converted to the covalent bonds. The terpyridine-containing monolayer film anchoring on the substrate is very stable. Specially, the π-conjugated system of the terpyridyl 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 1,4-bis（2,2＇：6＇,2＇＇-terpyrid-4＇-yl） phenylene （Bi-tpy） and different transition metal ions （Mn^＋： Pt^4＋, Ru^3＋, Rh^3＋, Pd^2＋） were fabricated on the tpy-modified substrate, and well characterized using UV-Vis absorption spectroscopy. The UV-Vis analytic results indicate that the LBL Bi-tpy/Mn^＋ SA multilayer films, having an axial ligand between the metal atom and terpyridyl group, have been successfully fabricated and a progressive assembly runs regularly with almost equal amount of deposition in each cycle. Under illumination, the SA films on ITO show 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 was higher than that of Bi-tpy/Pt film. With an increase in the layer number, the photocurrent rose and reached its maximum at 6 bilayers. Further increment led to a current drop due to the increase in probability of objection and the cell re sistance. The results allow us to design new materials for more optoelectronic applications.

关 键 词：三联吡啶 过渡金属离子 层-层自组装 配位相互作用 光电性能 

分 类 号：O484.4[理学—固体物理]