Gas Adsorption Investigation on SiGe Monolayer: A First-Principle Calculation

Area of Science:

• Materials Science
• Computational Chemistry
• Surface Science

Background:

• Gas sensors are crucial for environmental monitoring and industrial safety.
• Developing novel materials with high sensitivity and selectivity is an ongoing challenge.
• Two-dimensional materials offer unique properties for sensing applications.

Purpose of the Study:

• To investigate the gas adsorption properties of various molecules on a SiGe monolayer.
• To evaluate the potential of SiGe monolayers as a sensing material for specific gases.
• To explore the influence of external electric fields on gas adsorption.

Main Methods:

• First-principles calculations were employed to simulate gas adsorption.
• Adsorption energies, band gaps, charge transfer, and electron localization functions were analyzed.
• Different adsorption sites and molecular orientations were considered.
• Current-voltage (I-V) characteristics for NH₃ adsorption were investigated.

Main Results:

• SiGe monolayer exhibits strong physical adsorption for SO₂, NO, NH₃, and O₂.
• NO₂ shows chemical adsorption on SiGe monolayer.
• External electric fields can modulate adsorption strength, inducing desorption for NH₃.
• SiGe monolayer demonstrates significant sensitivity to these gases.

Conclusions:

• SiGe monolayer is a promising candidate for developing sensitive gas sensors.
• The material's adsorption properties can be tuned by external electric fields.
• Further investigation into I-V characteristics of NH₃ adsorption is warranted.