Issue 51, 2017

Novel III-Te–graphene van der Waals heterojunctions for optoelectronic devices

Abstract

Gallium telluride presents interesting properties for applications in optoelectronic devices, such as solar panels and radiation detectors. These applications, however, have been hindered due to the low mobility of charge carriers and short lifetime of photoexcitations in this material. In this work we propose that these limitations could be overcome by van der Waals heterostructures of recently exfoliated GaTe monolayers and graphene sheets, combining the high photoabsorption of the former with the ballistic transport of the latter. Our analysis indicates that such structures have a binding energy greater than that of graphene bilayers and that the band offset is such that transfer of photoexcited electrons from GaTe to graphene should be spontaneous. To investigate the consequences of the relative position of graphene's Dirac cone with the band edges of the photon absorber, we propose two hypothetical new materials with the same atomic arrangement as GaTe: InTe and TlTe. Thermodynamic and dynamical analyses indicate that monolayers of these crystals, which should also present high photoresponsivity, are stable. Specifically for the case of TlTe we found that the band edges should coincide with graphene's Dirac cone in the brillouin zone, resulting in optimal transfer of photoexcited carriers.

Graphical abstract: Novel III-Te–graphene van der Waals heterojunctions for optoelectronic devices

Article information

Article type
Paper
Submitted
22 Mar 2017
Accepted
29 May 2017
First published
26 Jun 2017
This article is Open Access
Creative Commons BY license

RSC Adv., 2017,7, 32383-32390

Novel III-Te–graphene van der Waals heterojunctions for optoelectronic devices

J. A. Olmos-Asar, C. R. Leão and A. Fazzio, RSC Adv., 2017, 7, 32383 DOI: 10.1039/C7RA03369A

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements