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NLO-based nitrobenzene sensing using defective BN nanosheets: a DFT study
1Department of Chemistry, Payame Noor University, P. O. Box 19395-3697, Tehran, Iran. msouri@pnu.ac.ir.
Physical Chemistry Chemical Physics : PCCP
|May 14, 2026
Summary
Defect engineering in boron nitride (BN) nanosheets significantly alters electronic and optical properties. This modification enhances nitrobenzene (NB) adsorption and boosts nonlinear optical (NLO) performance, paving the way for advanced materials.
Area of Science:
- Materials Science
- Computational Chemistry
- Nanotechnology
Background:
- Boron nitride (BN) nanosheets are promising 2D materials with tunable electronic and optical properties.
- Understanding defect engineering's impact on BN nanosheets is crucial for advanced material design.
- Nitrobenzene (NB) adsorption on BN nanosheets is relevant for sensing applications.
Purpose of the Study:
- To investigate the structural, electronic, and nonlinear optical (NLO) properties of pristine and defective BN nanosheets.
- To analyze the adsorption behavior and interactions of nitrobenzene (NB) with engineered BN nanosheets.
- To explore the potential of defect engineering for developing enhanced optoelectronic and sensing materials.
Main Methods:
- Density Functional Theory (DFT) and time-dependent DFT (TD-DFT) calculations were employed.
- Structural, electronic, and optical properties were examined for various defect types (carbon substitution, vacancies).
- Natural Bond Orbital (NBO) analysis was used to understand adsorption mechanisms and charge transfer.
Main Results:
- Defect engineering significantly reduced the HOMO-LUMO gap and improved charge polarization in BN nanosheets.
- Optical absorption spectra showed a notable red shift, with vacancy defects broadening photo-response into the visible spectrum.
- Adsorption mechanisms of NB varied, with dative bonding and non-covalent interactions playing key roles, influencing adsorption energy and charge transfer.
- Complexation with NB notably enhanced hyperpolarizabilities (β, γ), especially for VN-NB, showing over 6000% increase in β.
Conclusions:
- Precise defect engineering in BN nanosheets offers a systematic approach to tailor electronic and optical characteristics.
- Defect engineering profoundly influences molecular adsorption mechanisms and strengths.
- Engineered BN nanosheets show significant potential for enhanced optoelectronic devices and chemical sensing applications.
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