J Am Chem Soc. 2013 Nov 6;135(44):16533-44. doi: 10.1021/ja407659z.
The controlled deposition of metal complexes from solution on inorganic surfaces offers access to functional materials that otherwise would be elusive. For such surface-confined interfaces to form, specific assembly sequences are often used. We show here that varying the assembly sequence of two well-defined and iso-structural osmium and ruthenium polypyridyl complexes results in interfaces with strikingly different spectroelectrochemical properties. Successive deposition of redox-active layers of osmium and ruthenium polypyridyl complexes, leads to self-propagating molecular assemblies (SPMAs) with distinct internal interfaces and individually addressable components. In contrast, the clear separation of these interfaces upon sequential deposition of these two complexes, results in charge trapping or electrochemical communication between the metal centers, as a function of layer thickness and applied assembly sequence. The SPMAs were characterized using a variety of techniques, including: UV–vis spectroscopy, spectroscopic ellipsometry, electrochemistry, synchrotron X-ray reflectivity, angle-resolved X-ray photoelectron spectroscopy, and spectroelectrochemistry. The combined data demonstrate that the sequence-dependent assembly is a decisive factor that influences and provides the material properties that are difficult to obtain otherwise.
从溶液中控制金属配合物在无机表面上的沉积为功能材料的制备提供了一种途径，否则这些功能材料将难以获得。为了形成这种表面受限的界面，通常使用特定的组装序列。我们在这里表明，改变两个结构明确且同构的钌和锇多吡啶配合物的组装顺序会导致具有显著不同光谱电化学性质的界面。氧化还原活性层的连续沉积导致具有独特内部界面和可单独寻址组件的自蔓延分子组装体（SPMAs）。相比之下，当这两种配合物按顺序沉积时，这些界面的明显分离会导致电荷捕获或电化学通信，这取决于层厚度和施加的组装顺序。使用多种技术对 SPMAs 进行了表征，包括：紫外-可见光谱、光谱椭圆偏振术、电化学、同步加速器 X 射线反射率、角分辨 X 射线光电子能谱和光谱电化学。综合数据表明，序列依赖性组装是一个决定性因素，它影响并提供了其他方法难以获得的材料特性。
