YNbC, novel Janus MXene: a first-principles study.
- 1Department of Physics, Razi University Kermanshah Iran [email protected].
Abstract
The unique out-of-plane structural asymmetry of Janus MXenes makes them an attractive class of two-dimensional materials, enabling flexibility in tailoring their physical properties. Employing first-principles calculations, we systematically explored the structural stability, mechanical properties, electronic structure, and thermoelectric transport properties of the novel Janus YNbC monolayer in comparison with its parent Nb₂C and Y₂C MXenes. The mechanical and dynamic stability of the proposed structure was established through elastic-constant analysis and phonon-dispersion spectra, respectively. Cohesive-, formation-, and decomposition-energy analyses indicate favorable bonding with respect to isolated atoms and a metastable character relative to the considered parent-MXene phases. Its finite-temperature thermodynamic behaviour was investigated within the harmonic phonon approximation. The calculated mechanical properties indicate that YNbC possesses favorable mechanical robustness with characteristics intermediate between those of Nb₂C and Y₂C. Electronic-structure calculations reveal a substantial modification induced by Janus symmetry breaking. While the parent MXenes exhibit metallic characteristics, at the PBE level, Janus YNbC shows semimetallic behaviour, characterized by a small indirect band overlap of approximately 14.6 meV, whereas the HSE functional produces a finite indirect band gap of approximately 0.1 eV, indicating narrow-gap semiconducting behaviour at this level of theory. Furthermore, the calculated thermoelectric transport coefficients demonstrate a favorable thermoelectric response for YNbC compared with the parent MXenes. Overall, Janus engineering offers a promising route to transforming metallic MXenes into narrow-gap materials with favorable electronic thermoelectric transport properties. These results suggest that narrow-bandgap YNbC holds promise for electronic and thermoelectric applications.
Related
- Exciton states of HfO₂ and Janus HfSO monolayers: first-principles investigations.
- Pnictogen-codoping-induced magnetic anisotropy switching in Mn-doped WSTe Janus monolayers: a first-principles study.
- Janus XSSe (X = Sc, Ti, Zr, Nb, Pd) monolayers for toxic gas sensing: a comparative first-principles study of CH₂O, COCl₂, and O₃ adsorption.
- Multifunctional Properties of Novel X2FeH5 Hydrides (X = Ca, Mg, Ba): A First-Principles Study of Hydrogen Storage, Electronic, Optical, and Mechanical Behavior
- First-principles and device-level investigation of a novel double halide perovskite solar cell for sustainable energy applications
BibTeX
@article{mousavi2026ynbc,
title = {{YNbC, novel Janus MXene: a first-principles study.}},
author = {Hamze Mousavi and Moein Asshabi},
journal = {RSC advances},
year = {2026},
month = oct,
doi = {10.1039/d6ra06232f},
url = {https://europepmc.org/article/MED/42903973},
note = {CC BY},
}
RIS
TY - JOUR
TI - YNbC, novel Janus MXene: a first-principles study.
AU - Hamze Mousavi
AU - Moein Asshabi
PY - 2026
DA - 2026/10/20
JO - RSC advances
DO - 10.1039/d6ra06232f
UR - https://europepmc.org/article/MED/42903973
AB - The unique out-of-plane structural asymmetry of Janus MXenes makes them an attractive class of two-dimensional materials, enabling flexibility in tailoring their physical properties. Employing first-principles calculations, we systematically explored the structural stability, mechanical properties, electronic structure, and thermoelectric transport properties of the novel Janus YNbC monolayer in comparison with its parent Nb₂C and Y₂C MXenes. The mechanical and dynamic stability of the proposed structure was established through elastic-constant analysis and phonon-dispersion spectra, respectively. Cohesive-, formation-, and decomposition-energy analyses indicate favorable bonding with respect to isolated atoms and a metastable character relative to the considered parent-MXene phases. Its finite-temperature thermodynamic behaviour was investigated within the harmonic phonon approximation. The calculated mechanical properties indicate that YNbC possesses favorable mechanical robustness with characteristics intermediate between those of Nb₂C and Y₂C. Electronic-structure calculations reveal a substantial modification induced by Janus symmetry breaking. While the parent MXenes exhibit metallic characteristics, at the PBE level, Janus YNbC shows semimetallic behaviour, characterized by a small indirect band overlap of approximately 14.6 meV, whereas the HSE functional produces a finite indirect band gap of approximately 0.1 eV, indicating narrow-gap semiconducting behaviour at this level of theory. Furthermore, the calculated thermoelectric transport coefficients demonstrate a favorable thermoelectric response for YNbC compared with the parent MXenes. Overall, Janus engineering offers a promising route to transforming metallic MXenes into narrow-gap materials with favorable electronic thermoelectric transport properties. These results suggest that narrow-bandgap YNbC holds promise for electronic and thermoelectric applications.
SN - 2046-2069
ER -