Ce-Ag Active Bimetallic Pairs in Two-Dimensional SnS₂ for Enhancing NO₂ Sensing

Area of Science:

• Materials Science
• Nanotechnology
• Environmental Science

Background:

• Developing efficient gas sensors is crucial for environmental protection.
• Tin disulfide (SnS₂) is a promising material for gas sensing applications.
• Enhancing the performance of SnS₂-based sensors requires innovative modification strategies.

Purpose of the Study:

• To develop an advanced gas sensor with enhanced nitrogen dioxide (NO₂) detection capabilities.
• To investigate the effect of incorporating cerium-silver (Ce-Ag) bimetallic pairs into SnS₂.
• To understand the underlying mechanisms responsible for improved gas sensing performance.

Main Methods:

• Synthesis of Ce-Ag bimetallic modified SnS₂ (Ce-SnS₂-Ag).
• Gas sensing performance evaluation for NO₂ detection at various concentrations and temperatures.
• Density Functional Theory (DFT) calculations to elucidate structural and electronic properties.

Main Results:

• The 0.8% Ce-SnS₂-Ag sensor exhibited a high response (5.18) to 1 ppm NO₂ at 80 °C.
• A low limit of detection (LOD) of 100 ppb for NO₂ was achieved.
• DFT calculations confirmed Ce substitution in SnS₂, interlayer spacing expansion, and Ag atom anchoring, leading to modulated electronic structure and enhanced NO₂ adsorption.

Conclusions:

• Ce-Ag bimetallic modification significantly enhances the NO₂ gas sensing performance of SnS₂.
• The optimized electronic structure and charge transfer dynamics are key to the superior sensing capabilities.
• This work provides a new approach for functionalizing SnS₂ for advanced gas sensing applications.