Vacancy‐ and doping‐dependent electronic and magnetic properties of monolayer SnS₂

Abstract

We have performed first‐principles calculations to investigate the formation and migration of vacancies and doping with M (M = Ti, V, Co, Mo, W, Re) at the Sn sites and X (X = O, Se, Te) at the S sites in monolayer SnS2. We find that the formation energies for S vacancy under both Sn‐ and S‐rich environments are lower than those for Sn vacancy, indicating that the vacancies at the S sites are likely to be formed during the synthesis. Reducing the possibility of vacancy cluster formation, both the vacancies at the Sn and S sites remain robust due to high migration barrier. Additionally, SnS2 with the vacancies at the Sn sites induces magnetic ground states with a magnetic moment of 4.00 μB. Both the Sn‐ and S‐sites vacancies preserve the semiconducting nature of pristine SnS2 with band gaps of 2.47 eV and 0.30 eV, respectively. Furthermore, we find that the dopants Ti, V, Mo, W, Re can be easily incorporated at the Sn sites in monolayer SnS2 due to the low formation energies under the S‐rich environment. However, Co may not be easily incorporated into SnS2. The doping with M at the Sn sites induces magnetic ground states in non‐magnetic SnS2. Additionally, a long‐range magnetic ordering is observed in SnS2 doped with V, Co, and Mo. In contrast, easy incorporation of O, Se, and Te at the S sites under the Sn‐rich environment has been observed while the semiconducting nature of SnS2 preserves with small band gaps.

Vertically Stacked 2H‐1T Dual‐Phase MoS2 Microstructures during Lithium Intercalation: A First Principles Study

“…The large surface area and weak out‐of‐plane van der Waals (vdW) interactions in these materials, can overcome the current challenges of poor electronic conductivity and damaging volumetric fluctuations during the intercalation and de‐intercalation. These materials, therefore, can find applications as various components of LIBs and sodium‐ion‐batteries (SIBs), including electrolytes, separators, as well as electrodes 20‐24 . Interestingly, the first rechargeable LIB, marketed by Exxon in the 1970s, consisted of the TMD, TiS 2 , as the cathode 25 .…”

Activating the Basal Plane of Defective SnS2 Nanosheets for NH3 Gas Sensing

“…Alternatively, elemental doping and nanoarchitecture engineering have been employed to tune the electronic structures and the exposed edge sites to improve the gas physisorption and sensing characteristics of pure SnS 2 . 24 For instance, Ou et al reported the synthesis of SnS 2 planar nanodisks by a facile oil-phase method, showing the high NO 2 -sensing response at 160 °C due to the facilitated physisorption and rich active edge sites. 25 The physisorption always presents weak selectivity to different adsorbates, whereas a synergy with chemisorption will be highly desired for the selective sensing.…”

“…One representative example was the SnS 2 /SnO 2 heterostructure wherein the SnS 2 –SnO 2 interface played a vital role for the gas adsorption and NH 3 -sensing performance. , However, the uneven distribution of the interface may impose an obstacle in the regulation of sensing behaviors and the precise understanding of interface effects. Alternatively, elemental doping and nanoarchitecture engineering have been employed to tune the electronic structures and the exposed edge sites to improve the gas physisorption and sensing characteristics of pure SnS 2 . For instance, Ou et al reported the synthesis of SnS 2 planar nanodisks by a facile oil-phase method, showing the high NO 2 -sensing response at 160 °C due to the facilitated physisorption and rich active edge sites .…”

Ab initio methods for the computation of physical properties and performance parameters of electrochemical energy storage devices

“…In practical situations, some researchers simplify the form of the diffusion pre-factor as D 0 = a 2 ν */2 with ν * given by the Debye frequency of the system. 169–171…”