Synergically engineering defect and interlayer in SnS₂ for enhanced room-temperature NO₂ sensing.

Area of Science:

• Materials Science
• Chemical Engineering
• Nanotechnology

Background:

• Defect and interlayer engineering are key strategies for enhancing gas sensing materials.
• Tuning electronic structures is crucial for improving sensor sensitivity and selectivity.
• Room-temperature gas sensing is highly desirable for practical applications.

Purpose of the Study:

• To develop an Al-doped SnS2 material with engineered defects and interlayer spacing for NO2 sensing.
• To investigate the synergistic effects of Al doping, sulfur vacancies, and expanded interlayer spacing on gas sensing properties.
• To achieve high-performance room-temperature NO2 detection.

Main Methods:

• Synthesis of ethylene glycol intercalated Al-doped SnS2 (EG-Al-SnS2).
• Fabrication and testing of the EG-Al-SnS2 material as a NO2 sensor at room temperature.
• In-situ near-ambient pressure X-ray photoelectronic spectroscopy (NAP-XPS) for surface electronic interaction analysis.
• Comparative experiments and theoretical calculations to elucidate the role of structural modifications.

Main Results:

• Pristine SnS2 failed to detect NO2 at room temperature.
• EG-Al-SnS2 exhibited improved conductivity and enabled room-temperature NO2 sensing.
• A high sensing response of 410% towards 2 ppm NO2 was achieved with 3% EG-Al-SnS2.
• Synergistic effects of Al doping, S vacancies, and expanded interlayer spacing enhanced NO2 interaction.

Conclusions:

• The developed EG-Al-SnS2 demonstrates superior NO2 sensing performance at room temperature.
• Engineered defects and interlayer spacing are effective strategies for improving gas sensor materials.
• The study provides insights into the mechanism of enhanced gas sensing through structural modification.