Czyszczon-Burton Thomas M, Montes Enrique, Prana Jazmine, Chen Sully F, Pakhanyan Christopher P, Vázquez Héctor, Inkpen Michael S
Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States.
Institute of Physics, Czech Academy of Sciences, Cukrovarnická 10, Prague 16200, Czech Republic.
Nano Lett. 2025 Jun 4;25(22):9125-9131. doi: 10.1021/acs.nanolett.5c01892. Epub 2025 May 23.
The influence of changing electrode material on the electrical and mechanical properties of metal-molecule-metal junctions is relatively poorly understood, yet an improved understanding of these interfaces remains critical to the implementation of such systems as active elements in real-world circuits. Accordingly, here we study single-molecule junctions comprising thioether-linked alkane and oligophenyl wires formed under an inert atmosphere using gold, silver, and copper electrodes. Break junction experiments and computational simulations reveal that the conductance of junctions with different contacts typically decreases in the order gold > silver ≥ copper. Such trends cannot be explained solely from the differences in work function for these metals, which are modulated in junctions by the interface dipole. Transport calculations also expose the influence of electronic coupling to the electrodes, which is strongest for gold. Together, this study charts a coherent path toward a more complete understanding of the role of the electrode in single-molecule devices.
改变电极材料对金属-分子-金属结的电学和力学性能的影响相对来说了解较少，然而，更好地理解这些界面对于将此类系统用作实际电路中的有源元件仍然至关重要。因此，我们在此研究在惰性气氛下使用金、银和铜电极形成的包含硫醚连接的烷烃和寡聚苯基导线的单分子结。断结实验和计算模拟表明，具有不同接触的结的电导通常按金>银≥铜的顺序降低。这种趋势不能仅由这些金属的功函数差异来解释，这些差异在结中由界面偶极调制。输运计算还揭示了电子耦合到电极的影响，这对金来说最强。总之，这项研究为更全面地理解电极在单分子器件中的作用绘制了一条连贯的路径。
