Unique Omnidirectional Negative Poisson’s Ratio in δ-Phase Carbon Monochalcogenides

Abstract

Auxetic materials (negative Poisson's ratio) are of exceptional importance for nanomechanical applications. Using first-principles calculations, we propose two-dimensional δ-phase carbon monochalcogenides (δ-CS, δ-CSe, and δ-CTe) with very strong auxeticity. In contrast to the known two-dimensional materials, we find that Poisson's ratio is negative in all crystal directions. In addition, the δ-phase carbon monochalcogenides turn out to be direct or quasi-direct bandgap semiconductors with impressive absorption of solar radiation.

Electronic, Magnetic, and Optical Performances of Non-Metals Doped Silicon Carbide

“…The last few decades, 2D materials ( Li and Kaner, 2008 ; Liu et al, 2014 ; Zhong et al, 2019 ; Luo et al, 2021 ) have been extensively used in optoelectronics ( Stankovich et al, 2006 ; Bratschitsch, 2014 ; Cui et al, 2021a ; Sun et al, 2021 ), catalysis ( Ziletti et al, 2015 ; Wang et al, 2018 ), spintronic devices ( Komsa et al, 2012 ; Sun et al, 2017a ; Li et al, 2021 ), energy conversion ( Pospischil et al, 2014 ; Cui et al, 2020a ; Sun et al, 2019 ; Sun and Schwingenschlögl, 2020 ), and gas sensing ( Kooti et al, 2019 ; Cui et al, 2020b ) for their unique structural, optical, electronic and magnetic properties ( Eddy and Gaskill, 2009 ; Castelletto et al, 2014 ; Yuan et al, 2018 ; Sun and Schwingenschlögl, 2021 ). Considering the high thermal capability and carrier mobility of bulk SiC ( Mélinon et al, 2007 ; Susi et al, 2017 ; Ferdous et al, 2019 ), the theoretical and experimental research on 2D SiC has aroused significant attention ( Hsueh et al, 2011 ; Chowdhury et al, 2017 ; Chabi and Kadel, 2020 ).…”

Electronic and optical properties of two-dimensional heterostructures based on Janus XSSe (X = Mo, W) and Mg(OH)2: a first principles investigation

“…[27][28][29][30][31] In order to expand the application of these layered materials, more interesting properties were developed by the prediction of 2D materials. [32][33][34][35][36] For example, d-phosphorene was proposed to be an auxetic material with a high negative Poisson's ratio (NPR) of about À0.267 along relative direction. 37 FeB 2 monolayer possesses a Dirac cone, which endows it with a Fermi velocity larger than that of graphene.…”

Theoretical Study on Electronic, Magnetic and Optical Properties of Non-Metal Atoms Adsorbed onto Germanium Carbide

“…An increasing number of new 2D materials have been investigated by first-principles calculations, including not only single-atom crystals [ 7 , 8 ], but also II–VI group compounds [ 9 ], III–V group compounds [ 10 , 11 ] and IV-IV group compounds [ 12 , 13 , 14 ]. These 2D materials have shown their advantages in the fields of spintronics [ 15 , 16 ], optoelectronics [ 17 , 18 , 19 , 20 ], energy conversion [ 21 , 22 ], catalysis [ 23 , 24 , 25 , 26 ] and gas sensing [ 27 , 28 , 29 ].…”