Rectify Effect of Pedot:PSS/WS₂ Heterostructure

Abstract

Recently, devices based on organic and two-dimensional (2D) materials have been recognized as the easiest way to fabricate hybrid 2D van der Waals (vdW) heterojunction devices for electronic and optoelectronic applications. Depositing organic materials on 2D materials is typically demonstrated by thermal evaporation using high voltage and vacuum systems. In this paper, a simple way to fabricate organic/n-2D heterostructures, where Pedot:PSS is chosen to be the organic material due to its high conductivity, excellent film forming ability and good stability, while WS 2 is selected as the n-2D material due to its well-known properties has been presented. By systematically studying the gate dependent and temperature-dependent I-V characteristics of the Pedot:PSS/WS 2 heterojunctions, it is demonstrated that the device shows a diode-like behavior with rectification ratio (RF) of %5 and a turn on voltage of %2 V at room temperature (RT). Furthermore, the rectification ratio of the junction reaches up to 10 3 using a back-gate bias voltage (V gs ) of 20 V together with drain-source voltage (V ds ) ranging from À4 to 4 V. On the basis of the results, it is demonstrated that this simple technique of fabricating organic/2D vdW heterojunctions can extend to other organics and 2D materials.

A Bilayer 2D-WS2/Organic-Based Heterojunction for High-Performance Photodetectors

“…Due to the excellent flexibility of organic materials, the surface of the isolated 2D WS 2 layers could be effectively smoothed out and interconnected together, filling pinholes and vacancies of the 2D layers underneath. Recently, research has been intensively carried out to combine 2D inorganic materials with organic materials to form energy-favorable junctions for efficient exciton dissociation and charge transport [28,29,30,31,32,33,34]. Two-dimensional CsPbBr 3 nanosheets have been assembled into flexible heterojunction films with phenyl-C61-butyric acid methyl ester (PCBM), and the 2D CsPbBr 3 /PCBM photodetectors exhibited an enhanced responsivity of 10.85 AW −1 and an ultrahigh detectivity of 3.0 × 10 13 Jones [30].…”

A two-dimensional MoS2/C3N broken-gap heterostructure, a first principles study

“…Vertical 2D devices based on 2D semiconductor heterojunctions have ideal band gap, high speed and larger power than traditional bulk junctions due to the short current path and large current cross. 16,17 According to the band alignment of the two dissimilar 2D materials, there exist three types of heterostructures. The heterostructures with different type interface have different applications elds.…”

Rectifying Effect of the Sr3Al2O6/Ga2O3 Heterojunction

“…Indicated by Figure b, under the 254 nm UV light illumination, the forward current at 0.5 V is about 700 times than that at the reverse bias of −0.5 V, leading to a rectified ratio, I (0.5 V)/ I (−0.5 V), of 700. With the increasing applied voltages, the rectified ratio decreased to be ≈20 at ±5 V due to current leakage, possibly attributed to the non‐ideal films and/or heterojunction interface quality, suggesting a strong dependence on the applied voltages . As the same trend in the dark, the rectified ratios decreased from 49 at ±0.5 V to 11 at ±5 V, as shown in Figure b.…”