A recent study led by Dr. Zeila Zanolli of the ICN2 Theory and Simulation group, on spectroscopic properties of few-layer tin chalcogenides, has been published on a special issue of the Journal of Physics Materials. This edition, called “Women’s Perspectives in Materials Science: 2D Materials”, will feature exclusively researches directed by female scientists, with the aim to highlight the excellent contributions of women to 2D Materials Science.
The Journal of Physics Materials has launched a special issue fully dedicated to the contributions of women to 2D Materials Science. The aim of this initiative is to give to distinguished female researchers recognition for their excellent work in this field and to support their career progression. Despite the increasing involvement of women in important research projects, they are still underrepresented in leadership positions, in plenary and invited speakers lists at conferences, in journal editorial boards, and so on. “Women’s Perspectives in Materials Science: 2D Materials” will be one of a series of focus issues highlighting excellent contributions made by women in all the areas of advanced materials science.
This special edition dedicated to recent progress in synthesis, characterization and applications of 2D materials and structures features a new work led by Dr. Zeila Zanolli of the ICN2 Theory and Simulation group. This study, developed within a collaboration between the ICN2, the University of Liège (Belgium) – with an important contribution by Dr Antoine Dewandre – and the University of Oxford (UK), aimed to investigate and model the structural, vibrational and electronic properties of tin chalcogenides (SnS and SnSe) and how their behaviour changes passing from a 3D to a 2D crystal and as a function of the number of layers of the structure.
Monochalcogenides as the compounds considered in this work have interesting properties, among which the fact that slabs of these materials act as semiconductors with low band gap and high mobility and are stable at room temperature. The reduction of the geometry of the crystal, of course, affects many of the characteristics of the material, thus it is necessary to investigate and describe them both theoretically and experimentally. For example, recent theoretical studies of electronic structure changes in few-layer Sn chalcogenides have shown a significant expansion of the band gap as the number of layers decreases.
Through calculation of electronic and phononic properties of slabs of mono- and few-layer Sn chalcogenide samples, the authors of this study identified spectroscopic signatures of 2D material thickness and propose several simple non-invasive techniques to discriminate different thickness samples. The outcome of this research provides useful tools for the experimental investigation of the properties of thin structures of these materials.
While Dr. Zanolli’s paper has already been published online (in open access), this special issue is not closed yet. In fact, contributions will be accepted until the end of January 2020 and published along the way. For more information, visit the journal website.
Article Reference:
Antoine Dewandre, Matthieu Jean Verstraete, Nicole Grobert and Zeila Zanolli, Spectroscopic properties of few-layer tin chalcogenides, Journal of Physics Materials, Women’s Perspectives in Materials Science: 2D Materials
DOI: https://doi.org/10.1088/2515-7639/ab3513
Acknowledgements:
Dr Zeila Zannolli’s reseach is funded by the Spanish Ministerio de Ciencia, Innovación y Universidades, by the Spanish Agencia Estatal de Investigación and the the Fondo Social Europeo, within the project: First principles engineering of novel nanomaterials for spintronics applications; grant number: RYC-2016-19344.
Image:
Representation of one of the surface vibration modes computed for the 4-layer slab of tin monosulfide (SnS). As the thickness of a material is reduced down to the nanoscale, prominent surface effects emerge due to the high surface-to-bulk ratio. Their signature can be identified and investigated using standard experimental technique, such as Raman vibrational spectroscopy. In thicker materials, the contribution of the inner atoms dominates the vibrational spectra and the surface vibrations cannot be detected. Frequency and amplitude of vibration are chosen to optimize the visualization.
Image Credits: The animation was produced by Antoine Dewandre using the Agate visualization tool developed by Jordan Bieder and available at: https://launchpad.net/~piti-diablotin/+archive/ubuntu/abiout