Versatile electrochemical approaches towards molecular electronic devices fabrication
The concept of molecular electronic devices (MEDs) has been evolved since the first theoretical report published in 1974. The theoretical article laid the foundation for understanding charge-transport phenomena by utilizing either a single molecule or numerous molecules sandwiched between two electrical conductors. Since then, many research groups have been engaged at molecular junction fabrication considering a variety of molecules including organic, inorganic, organometallic, polymers, biomolecules that can mimic electronic functions of traditional silicon-based devices. To date, most of the molecular junctions have been constructed using well explored molecular assemblies of thiolated derivatives adsorbed on mostly Au substrate. However, the Au-S bond is not considered a true covalent bond in view of its surface bond energy which is ~ 1.9 eV, much less than pure covalent bond energy. Besides, Au-S interfaces suffer due to their reactivity, instability over time, and thus not suitable for world applications. Therefore, an alternative approach for molecular electronic junctions fabrication is must be foreseen to rule out all the difficulties mentioned above. Herein, we abridge hot off the press experiential outcomes on how electrochemical technique can be employed in making robust molecular layers on various substrates including Au, ZnO, SnO2, H-terminated Si, conductive carbon electrode that are suitable for reliable molecular electronics device fabrication for charge-transport studies. This fascinating electrochemical technique is appropriate for producing not only homostructure but also heterostructures molecular layers of desired thickness. We also discuss the pros and cons of the electrochemical process for growing molecular layers in the conclusion and outlook section.
- This article is part of the themed collection: Versatile Electrochemical Approaches