Study on SO₂ and Cl₂ sensor application of 2D PbSe based on first principles calculations

Area of Science:

• Materials Science
• Nanoscience
• Computational Chemistry

Background:

• Two-dimensional (2D) materials offer unique properties for sensing applications.
• Developing selective and sensitive gas sensors for pollutants like SO₂ and Cl₂ is crucial.

Purpose of the Study:

• To investigate the potential of 2D lead selenide (PbSe) for detecting SO₂ and Cl₂.
• To analyze the adsorption mechanisms and electronic structure changes in 2D PbSe upon exposure to these gases.

Main Methods:

• First-principles calculations were employed to study the atomic structure, band gap, and charge distribution of 2D PbSe.
• Adsorption energies and electronic properties were calculated for SO₂ and Cl₂ on 2D PbSe.

Main Results:

• 2D PbSe exhibits distinct adsorption capabilities for both SO₂ and Cl₂.
• Gas adsorption leads to electron transfer from PbSe to gas molecules, significantly reducing the band gap.
• Single-layer PbSe shows higher sensitivity to Cl₂ (60.61% band gap reduction), while multi-layer PbSe is more sensitive to SO₂ (72.97% band gap reduction).

Conclusions:

• 2D PbSe is a viable candidate for designing highly sensitive gas sensors for SO₂ and Cl₂.
• The distinct sensitivities of single-layer and multi-layer PbSe to different gases offer opportunities for selective detection.