Transporte de carga en una unión molecular basada en disulfuro de molibdeno.

Abstract

Molecular electronics, in which a single molecule is oriented between two electrodes to form an electronic nano-device, has the potential to overcome the miniaturization difficulties of conventional silicon technology. While metallic electrodes are commonly used to study charge transport at molecular junctions in detail, the use of semiconductor electrodes has attracted increasing attention due to the emergence of new junction properties, such as current rectification. In this contribution, we study non-centrosymmetric single-molecule junctions formed from 4,4’-biphenyldithiol molecular bridges on a molybdenum disulfide (MoS2) electrode. Multilayer nanosheets were obtained by liquid-phase exfoliation of MoS2 powder and then deposited using the drop-casting method to obtain a semiconductor electrode. This research is complemented by chemical and surface characterization using Ultraviolet-visible, Fourier Transform Infrared, Raman and X-Ray Photoelectron spectroscopies; quartz crystal microbalance and atomic force microscopy of both, nanosheets and electrodes. Also, the I(s) technique based on scanning tunneling microscopy was applied to evaluate the conductance of the Au-molecule-MoS2 junctions. Finally, the Current-Voltage (I-V) curve is reported, exhibiting an asymmetric shape. In summary, this study is a first approach to the use of MoS2 semiconductor nanoelectrodes to promote the rectification of molecular junctions.