Stability and electronic properties of sulfur terminated two-dimensional early transition metal carbides and nitrides (MXene)

Effect of the sulfur termination on the properties of Hf2CO2MXene

“…However, due to the difference in electronegativity χ (O) = 3.5 and χ (S) = 2.5, we expect some differences in electronic and bonding properties between Hf 2 CO 2 MXene and its partially S-terminated structures. According to published work, fully sulfurized Hf 2 CS 2 21 exhibits metallic behavior, whereas pristine Hf 2 CO 2 has a theoretical band gap of 1.79 eV 50 and varies between 1.66 eV 51 and 1.59 eV 52 with the HSE06 approximation. We have performed hybrid HSE06 calculations in order to analyze the band gap value change between Hf 2 CO 2 MXene and Janus states.…”

“…20 Among them, Hf-based MXenes have been reported to be stable whether the termination surfaces are fully replaced by the sulfur atoms. 21 Indeed, the calculation of S or O adsorption on the bare Hf 2 C monolayer was found favorable on its hollow site, allowing the construction of Hf 2 CO 2 or Hf 2 CS 2 MXenes. Furthermore, different functionalities have been explored by considering the use of two different terminations of the MXene, constituting Janus structures.…”

Rationally Designed High-Performance Spin Filter Based on Two-Dimensional Half-Metal Cr2NO2

“…Recently, some 2D transition metal carbides and nitrides, known as MXene, have been shown to possess magnetic properties. [25][26][27][28][29][30][31] For instance, magnetic behavior was observed for the first time by Barsoum and co-workers in Ti 3 C 2 MXenes. 31 2D Cr-based MXene (Cr 2 NO 2 ) was investigated by using Monte Carlo simulations and showed half-metallic behavior with a Curie temperature of 566 K. 25 Similar to Fe 3 GeTe 2 , the stacking of Cr atoms in the vertical direction resulted in high Curie temperature.…”

Element‐Doped Mxenes: Mechanism, Synthesis, and Applications

“…For example, molecular dynamics simulations and phonon frequency analysis are used to predict the most stable S terminated MXene, which is of great benefit to the design of rechargeable batteries. [228] As for the T-doped MXene, it is also practical to predict the MXene with the most active HER and calculate the most adjustable surface terminal group for the MXene. [229] MXene, as a 2D material with good optical, electrical, and magnetic properties, has extensively studied, but there is still a long way to go in the exploration of its performance optimization by the means of theoretical calculation.…”

“…For example, molecular dynamics simulations and phonon frequency analysis are used to predict the most stable S terminated MXene, which is of great benefit to the design of rechargeable batteries. [ 228 ]…”