Optoelectronic Characterization of 2D Graphene‐Based Heterostructures: Gr/MoS₂ and Gr/WS₂

Abstract

The aim of this research is to obtain and to compare the electrical conductivity and the transmittance of two heterostructures: Gr/WS2 and Gr/MoS2 on quartz. Raman spectroscopy is used to analyse the quality of the samples before and after the measurements. Terahertz time domain spectroscopy (THz‐TDS) in transmission mode is used as a non‐destructive technique to obtain the surface conductivity and the transmittance in the frequency range [0.2, 1.6] THz. The transmittance values obtained for both samples are similar, whereas the surface conductivity of Gr/WS2 is higher than the one of Gr/MoS2 and both are higher than the conductivity values obtained for individual homogeneous layers. FT‐IR and UV‐Vis spectroscopies are used to obtain the optical transmittance and to evaluate the behaviour of each layer in the frequency ranges [90, 180] THz and [300, 1200] THz, respectively. In the IR range, the transmittance of the heterostructures is similar to that of the individual materials, although in the visible range the transmittance is totally dominated by the WS2 and MoS2 layers. These characteristics make these heterostructures good candidates to be used for optoelectronics sensors.This article is protected by copyright. All rights reserved.