Ni-Doped SnO Microplates for Carbon Monoxide Gas Detection

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Tin(II) oxide (SnO) is a promising semiconductor material for gas sensing applications.
• Carbon monoxide (CO) is a toxic gas requiring sensitive and reliable detection methods.
• Doping is a common strategy to enhance the properties of semiconductor materials for improved performance.

Purpose of the Study:

• To investigate the effect of nickel (Ni) doping on SnO nanostructures for CO gas detection.
• To analyze the structural, electronic, and sensing properties of Ni-doped SnO.
• To explore the mechanism behind enhanced CO sensing performance in Ni-doped SnO.

Main Methods:

• Microwave-assisted hydrothermal synthesis for undoped and Ni-doped SnO nanostructures.
• Scanning electron microscopy (SEM) for morphological analysis.
• X-ray photoelectron spectroscopy (XPS) for surface composition and chemical state analysis.
• Density functional theory (DFT) calculations for theoretical investigation of doping effects.
• Electrical measurements for gas sensing performance evaluation.

Main Results:

• SEM confirmed the formation of micrometric plates with a predominant SnO phase.
• XPS verified the SnO phase and the absence of NiOₓ on the surface.
• Ni doping increased carrier concentration and conductivity.
• DFT calculations revealed enhanced CO affinity due to Ni doping via carbon coordination.
• Ni-doped SnO exhibited a decrease in activation energy, facilitating room-temperature operation.

Conclusions:

• Ni-doped SnO nanostructures synthesized via microwave-assisted hydrothermal method show significant potential for CO gas sensing.
• The enhanced CO detection is attributed to increased conductivity and improved CO affinity induced by Ni doping.
• The material's ability to operate at room temperature makes it highly desirable for practical CO sensor applications.