Unusual thermo-mechanical properties of the Janus Mo2ScC2OH MXene monolayer.

Abstract

In this study, we investigated the structural, electronic, mechanical, dynamical, and thermal properties of the Janus Mo2ScC2OH MXene monolayer using ab initio calculations based on density functional theory. The results showed that Janus Mo2ScC2OH is metallic and mechanically stable. We found that Mo2ScC2OH has high Poisson's ratio. Phonon dispersion calculations revealed that there are no imaginary frequencies, suggesting that the Janus Mo2ScC2OH monolayer is dynamically stable. Debye temperature, Grüneisen parameters, thermodynamic properties, and lattice thermal conductivity have also been calculated. The results revealed that Mo2ScC2OH has high negative Grüneisen parameters, indicating that it could be a negative thermal expansion material. Additionally, we noted that the Janus Mo2ScC2OH monolayer exhibits a relatively low lattice thermal conductivity, with a notable contribution from the ZA mode.