Hydrothermal synthesis and characterization of selenium-doped MoS₂ for enhanced optoelectronic properties

Research Lab for Energy Systems, Department of Physics, Netaji Subhas University of Technology, New Delhi, India

^* Corresponding author: shreyasharma.aug15@gmail.com

Abstract

Transition metal dichalcogenides show layered crystal structure with Van der Waals forces spanning the adjacent layers. Robust covalent bonds within each 2D sheet contribute to their outstanding electrical and optical properties. The incorporation of a chalcogen atom as a composite leads to enhanced optical and electrical characteristics of the TMDs, which could make them potential candidates for opto-electronic applications. In the present study, we have described the synthesis and characterizations of Se doped MoS₂ nanolayers using a facile one-step hydrothermal method. XRD analysis revealed the diffraction peaks corresponding to MoS₂ as well as Se which suggested the successful incorporation of selenium into MoS₂ nanolayers. Optical analysis revealed an increased band gap of 1.01 eV after the addition of selenium, determined through UV-visible spectroscopy with a refractive index of 3.36. The morphological analysis by FESEM showed the formation of nanolayers and the EDX pattern showed the presence of Mo, S and Se. The enhanced bandgap of the as-synthesized material and the increased absorption in the UV region ensures its usage for the fabrication of efficient broadband photodetectors. Our future research focuses on the potential application of Se doped MoS₂ nanolayers in the field of efficient photodetectors.