Janus XSSe (X = Sc, Ti, Zr, Nb, Pd) monolayers for toxic gas sensing: a comparative first-principles study of CH₂O, COCl₂, and O₃ adsorption.
- 1Department of Physics, Mawlana Bhashani Science and Technology University Tangail-1902 Bangladesh [email protected] [email protected].
- 2Department of Physics, Bangladesh University of Textiles Dhaka Bangladesh.
- 3Department of Physics, Dhaka Commerce College Dhaka Bangladesh.
Abstract
In this study, Janus ScSSe, TiSSe, ZrSSe, NbSSe, and PdSSe monolayers were systematically examined as sensing materials for oxygen-containing toxic gases (CH₂O, COCl₂, and O₃) using density functional theory (DFT). Adsorption was investigated on both the S- and Se-terminated surfaces of the all nanosheets. Key sensing descriptors, including adsorption energy, charge transfer, recovery behavior, electronic modulation, and RDG analysis upon gas interaction, were analyzed to elucidate the underlying adsorption mechanisms. Our results reveal that ScSSe, ZrSSe, and NbSSe exhibit strong affinity toward all three gas molecules, accompanied by pronounced electronic perturbations, particularly for O₃. In contrast, TiSSe and PdSSe display weak physisorption interactions. Mulliken charge analysis further shows that CH₂O and COCl₂ act as electron donors, whereas O₃ behaves as an electron acceptor for all the monolayers. ScSSe exhibits pronounced electronic modulation, with a large DOS change (up to 65.35%) together with significant work-function shifts (-8.71% for COCl₂ and -6.29% for O₃), suggesting its promising dual-mode sensing capability. The strong adsorption of ScSSe, driven by its high adsorption energy, naturally results in slower desorption and favorable recovery times. TiSSe recovers in the microsecond range (10⁻⁵ to 10⁻⁷ s), while ZrSSe and NbSSe fall within the millisecond to near-microsecond range (10⁻⁴ to 10⁻² s and 10⁻⁵ to 10⁻² s). PdSSe shows ultrafast nanosecond recovery (10⁻¹¹ to 10⁻⁷ s). Work-function shifts across all monolayers confirm their tunable sensing behavior. Selectivity analysis against atmospheric gases (N₂, O₂, and H₂O) shows minimal interference, with charge transfer below 0.002 e. Co-adsorption results confirm stable sensing under humid conditions, as target gases retain strong adsorption. RDG analysis indicates predominantly noncovalent interactions, with stronger interaction characteristics observed for O₃ adsorption on ScSSe. Overall, ScSSe, NbSSe, and ZrSSe demonstrate promising potential as nano-sensing materials CH₂O, COCl₂, and O₃ detection.
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.
- Tailoring the Gas Sensing Performance of ZrS2 Monolayers via Noble Metal Doping for Thermal Runaway Gas Detection in LIBs: A First-Principles Study
- Hunting the Enhanced Interaction of Donors with Post-Transition and Transition Metal Dichalcogenides: Comparative Study of NO ₂ , H ₂ S, NH ₃ , and Aniline Adsorption on MoS ₂ , SnS ₂ , and ZrS ₂ Monolayers
- Remarkably enhanced second harmonic generation in Janus HfXY (X, Y = O, S, Se, Te; X ≠ Y) monolayers
BibTeX
@article{shamim2026janus,
title = {{Janus XSSe (X = Sc, Ti, Zr, Nb, Pd) monolayers for toxic gas sensing: a comparative first-principles study of CH₂O, COCl₂, and O₃ adsorption.}},
author = {Siraj Ud Daula Shamim and Sifat Reza Khoshnobish and Anirbun Paul Arko and Tanu Arefin and Shamiul Alam and Afiya Akter Piya},
journal = {RSC advances},
year = {2026},
month = oct,
doi = {10.1039/d6ra08486a},
url = {https://europepmc.org/article/MED/42910250},
note = {CC BY-NC},
}
RIS
TY - JOUR
TI - Janus XSSe (X = Sc, Ti, Zr, Nb, Pd) monolayers for toxic gas sensing: a comparative first-principles study of CH₂O, COCl₂, and O₃ adsorption.
AU - Siraj Ud Daula Shamim
AU - Sifat Reza Khoshnobish
AU - Anirbun Paul Arko
AU - Tanu Arefin
AU - Shamiul Alam
AU - Afiya Akter Piya
PY - 2026
DA - 2026/10/21
JO - RSC advances
DO - 10.1039/d6ra08486a
UR - https://europepmc.org/article/MED/42910250
AB - In this study, Janus ScSSe, TiSSe, ZrSSe, NbSSe, and PdSSe monolayers were systematically examined as sensing materials for oxygen-containing toxic gases (CH₂O, COCl₂, and O₃) using density functional theory (DFT). Adsorption was investigated on both the S- and Se-terminated surfaces of the all nanosheets. Key sensing descriptors, including adsorption energy, charge transfer, recovery behavior, electronic modulation, and RDG analysis upon gas interaction, were analyzed to elucidate the underlying adsorption mechanisms. Our results reveal that ScSSe, ZrSSe, and NbSSe exhibit strong affinity toward all three gas molecules, accompanied by pronounced electronic perturbations, particularly for O₃. In contrast, TiSSe and PdSSe display weak physisorption interactions. Mulliken charge analysis further shows that CH₂O and COCl₂ act as electron donors, whereas O₃ behaves as an electron acceptor for all the monolayers. ScSSe exhibits pronounced electronic modulation, with a large DOS change (up to 65.35%) together with significant work-function shifts (-8.71% for COCl₂ and -6.29% for O₃), suggesting its promising dual-mode sensing capability. The strong adsorption of ScSSe, driven by its high adsorption energy, naturally results in slower desorption and favorable recovery times. TiSSe recovers in the microsecond range (10⁻⁵ to 10⁻⁷ s), while ZrSSe and NbSSe fall within the millisecond to near-microsecond range (10⁻⁴ to 10⁻² s and 10⁻⁵ to 10⁻² s). PdSSe shows ultrafast nanosecond recovery (10⁻¹¹ to 10⁻⁷ s). Work-function shifts across all monolayers confirm their tunable sensing behavior. Selectivity analysis against atmospheric gases (N₂, O₂, and H₂O) shows minimal interference, with charge transfer below 0.002 e. Co-adsorption results confirm stable sensing under humid conditions, as target gases retain strong adsorption. RDG analysis indicates predominantly noncovalent interactions, with stronger interaction characteristics observed for O₃ adsorption on ScSSe. Overall, ScSSe, NbSSe, and ZrSSe demonstrate promising potential as nano-sensing materials CH₂O, COCl₂, and O₃ detection.
SN - 2046-2069
ER -