MoS₂-NiO nanocomposite for H₂S sensing at room temperature

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• 2-D materials like molybdenum disulfide (MoS2) are promising for low-concentration H2S gas detection.
• Hydrogen sulfide (H2S) is a toxic gas requiring sensitive and reliable detection methods.

Purpose of the Study:

• To design and synthesize novel MoS2 and NiO nanocomposites for H2S gas sensing.
• To evaluate the sensing performance of these nanocomposites, focusing on sensitivity, selectivity, and stability.

Main Methods:

• Nanocomposites synthesized via a simple hydrothermal method.
• Characterization using XRD, SEM, TEM, HRTEM, BET, and XPS.
• Gas sensing performance evaluated at room temperature (RT).

Main Results:

• The MNO-10 nanocomposite exhibited the highest response (6.3) to 10 ppm H2S, significantly outperforming pure NiO.
• The MNO-10 sensor showed excellent selectivity, rapid response/recovery (50/20 s), long-term stability (28 days), reproducibility, and a low detection limit (2 ppm).
• Enhanced performance attributed to MoS2's layered structure, high BET surface area, active sites, and synergistic effects with NiO.

Conclusions:

• MoS2/NiO nanocomposites offer a promising platform for highly sensitive and stable H2S gas detection.
• The simple fabrication method and excellent performance present a novel approach for H2S sensing applications.
• Synergistic effects between MoS2 and NiO are crucial for the enhanced gas sensing properties.