Bias Tunable Transport Modulation and Gas Selectivity in Layered BiOI: A DFT NEGF Study
Abstract
Understanding the interplay between adsorption energetics and charge-transport modulation is essential for the rational design of low-power and bias-tunable gas sensors. Here, we present a comprehensive first-principles study of gas selectivity in layered bismuth oxyiodide (BiOI) by integrating density functional theory with nonequilibrium Green's function transport calculations. The adsorption and bias-dependent transport responses toward NO2, NH3, CO2, and representative volatile organic compounds are systematically examined. While NH3 and NO2 exhibit strong chemisorption and localized electronic perturbations, CO2 interacts through weak physisorption, demonstrating that adsorption strength alone does not determine sensing performance. Instead, the evolution of transmission channels near the Fermi level governs the sensing response. Bias-dependent calculations reveal an electrically tunable sensitivity hierarchy, in which weakly adsorbed CO2 preserves conductive pathways and exhibits pronounced low-bias sensitivity despite minimal charge transfer. Recovery-time analysis further highlights the trade-off between transport modulation and reversibility for strongly adsorbed species. These results establish a transport-centered selectivity framework for layered BiOI and provide mechanistic insight into electric-field-controlled gas sensing under ambient conditions.
Related
- Strain-Tunable High-Tc Superconductivity in Layered R3m B2CN
- Nonlinear Photocurrent Spectroscopy and Polarization-Tunable Shift Current in the Layered Semiconductor CuScP2S6
- Bias-Modulated Electronically-Tunable Optoelectronic Chromatic Dispersion in Ge PN Photodiodes
- Ultrafast and Anisotropic Exciton Transport in Layered NbOI2
- Bi12Rh3Ag6I9: Mobile Silver Ions and Surface-Dominated Transport in a Layered Weak Topological Insulator.
BibTeX
@misc{damte2026bias,
title = {{Bias Tunable Transport Modulation and Gas Selectivity in Layered BiOI: A DFT NEGF Study}},
author = {Jemal Yimer Damte and Jiří Houška and Pavel Baroch and Xue Yong},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2608.03308},
eprint = {2608.03308},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.03308},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Bias Tunable Transport Modulation and Gas Selectivity in Layered BiOI: A DFT NEGF Study
AU - Jemal Yimer Damte
AU - Jiří Houška
AU - Pavel Baroch
AU - Xue Yong
PY - 2026
DA - 2026/10/17
PB - arXiv
DO - 10.48550/arxiv.2608.03308
UR - https://arxiv.org/abs/2608.03308
AB - Understanding the interplay between adsorption energetics and charge-transport modulation is essential for the rational design of low-power and bias-tunable gas sensors. Here, we present a comprehensive first-principles study of gas selectivity in layered bismuth oxyiodide (BiOI) by integrating density functional theory with nonequilibrium Green's function transport calculations. The adsorption and bias-dependent transport responses toward NO2, NH3, CO2, and representative volatile organic compounds are systematically examined. While NH3 and NO2 exhibit strong chemisorption and localized electronic perturbations, CO2 interacts through weak physisorption, demonstrating that adsorption strength alone does not determine sensing performance. Instead, the evolution of transmission channels near the Fermi level governs the sensing response. Bias-dependent calculations reveal an electrically tunable sensitivity hierarchy, in which weakly adsorbed CO2 preserves conductive pathways and exhibits pronounced low-bias sensitivity despite minimal charge transfer. Recovery-time analysis further highlights the trade-off between transport modulation and reversibility for strongly adsorbed species. These results establish a transport-centered selectivity framework for layered BiOI and provide mechanistic insight into electric-field-controlled gas sensing under ambient conditions.
ER -