Effect of asymmetric metallic electrodes on electronic transport properties of tetracene molecular junction

By applying NEGF formalism combined with DFT, the electron transport properties of tetracene molecule stringed to asymmetric electrodes have been investigated. To induce asymmetry in the molecular junctions, the left electrode is kept as Au while the right electrode is varied with Ag, Cu and Pt in each case. A comparison between the rectification trends of the asymmetrical junctions is done by the analysis of current–voltage characteristics, transmission spectra and MPSH. The results depict that the rectification behaviour can be escalated by using dissimilar metallic electrodes. It is found that the tetracene molecule exhibits significant rectification behaviour with a peak rectification ratio of 3.41 when coupled with gold and copper electrode combination. In addition, NDR behaviour within a certain bias voltage is observed in all the molecular junctions with the highest PVCR of 1.78 in Au-Tetracene-Ag molecular junction. Our findings highlight that changing the electrode material would efficiently improve the characteristics of a metal–molecule-metal junction and can provide a guide for the design of functional molecular devices.