Surface Nanochemistry for Combinatorial Fabrication of Molecular Multilayered Films Toward Highly Efficient Molecular Devices

合成化学家面临的真正挑战之一是从简单的分子单位开始，通过自组装在固体表面上构建一个定义良好的纳米级结构或空间。金属络合的自组装和自组织结合有可能在表面上提供新的定义良好的纳米结构和功能。在本项目中，我们研究了面向分子器件表面的双核金属复合模块的逐层制备及其电化学功能。合成了以四足独立膦酸盐配体（XP）为构建模块的新型双核Ru/Os配合物[M(XP)(BL)M(XP)] （M=Ru and Os）。在ITO电极上对自组装单层的双核Ru/Os络合物[M(XP)(BL)M(XP)] （M=Ru和Os）进行AFM测量，得到了清晰的分子结构域图像。[M(XP)(BL)M(XP)]配合物在ITO电极上的电化学表现为+0.93 V （M=Ru）和+0.66 V （M=Os, r…）下的一步双电子过程。通过Zr（IV）与[M(XP)(BL)M(XP)]中的膦酸基团的配位，实现了表面的逐层生长。通过改变具有不同氧化还原电位的模块的顺序，可以构建不同的分子整流器电位序列。多层膜上的电子转移行为强烈依赖于分子组分内部的电位梯度。为了在固体表面上构建一个明确的纳米级二维结构，我们研究了金纳米终端之间的dna模板纳米线。选择吖啶（Acd）基作为配合物的插层基团。络合物[Ru(XP)(l - add)]作为分子点固定在云母表面，作为DNA捕获位点。我们发现DNA被表面的分子点捕获。从原子力显微镜测量。此外，在微米尺寸的Au/SiO_2图案化硅衬底上，两个Au末端被λ-DNA分子连接，并被钯纳米粒子金属化。少

One of the real challenges for synthetic chemists is to construct a well-defined nanometer-sized structure or space on solid surfaces by self-assembly, starting from simple molecular units. The combination of self-assembly with self organization by metal complexation has the potential to provide novel well-defined nanostructures and functions on surfaces. In this project, we have studied the layer-by-layer fabrication and electrochemical function of dinuclear metal complex modules on surface towards molecular devices. New dinuclear Ru/Os complexes, [M(XP)(BL)M(XP)] (M=Ru and Os), with tetrapod free-standing phosphonate ligand (XP) have been synthesized as a building module. The AFM measurement for the self-assembled monolayer of dinuclear Ru/Os complexes, [M(XP)(BL)M(XP)] (M=Ru and Os) on an ITO electrode provides dear molecular domain images. Electrochemistry of [M(XP)(BL)M(XP)] complex on ITO electrode showed a one-step two-electron process at +0.93 V for M=Ru and +0.66 V for M=Os, r … More espectively. Layer-by-layer growth on the surface was achieved by the help of Zr(IV) coordination to the phosphonate groups in [M(XP)(BL)M(XP)]. By changing the order of the modules with different redox potentials, the different potential sequence towards a molecular rectifier can be constructed. The electron transfer behaviors on the multilayer films strongly depend on the potential gradients within the molecular components.In order to construct a well-defined nanometer-sized 2D structure on solid surfaces, we have studied the DNA-templated nanowiring between Au nanoterminals. Acridine (Acd) group was chosen as an intercalating group in the complex. The complex, [Ru(XP)(L-Acd)] was immobilized on mica surface as molecular dots, which can act as a DNA trapping site. We found that DNA was captured by the molecular dots on the surface. From the AFM measurement. Further, two Au terminals on the micrometer-sized Au/SiO_2 patterned silicon substrate were connected by λ-DNA molecules, which was metallized by the Pd nanoparticles.. Less