Single Ni Atom-Dispersed WSe₂ Monolayer for Sensing Typical Fault Gases in Dry-Type Transformers: A First-Principles...

Area of Science:

• Materials Science
• Nanotechnology
• Physical Chemistry

Background:

• Dry-type transformers require monitoring for operational status.
• Carbon monoxide (CO) and formaldehyde (HCHO) are key indicators of transformer health.
• Novel gas sensing materials are needed for effective detection.

Purpose of the Study:

• To investigate the potential of Nickel-decorated Tungsten Diselenide (Ni-WSe2) monolayers as gas sensors.
• To evaluate the sensing capabilities of Ni-WSe2 for CO and HCHO detection.
• To assess the suitability of Ni-WSe2 for monitoring dry-type transformer operation.

Main Methods:

• First-principles theory calculations.
• Adsorption energy analysis.
• Band structure and Frontier molecular orbital analysis.
• Density of state (DOS) and work function (WF) analysis.

Main Results:

• Stable adsorption of Ni on the TW site of WSe2 monolayer with a binding energy of -4.33 eV.
• Ni-WSe2 exhibits chemisorption for CO and HCHO with adsorption energies of -2.27 eV and -1.37 eV, respectively.
• Significant sensing responses for CO (55.9%) and HCHO (30.9%) based on band gap changes.
• Modified electronic properties of Ni-WSe2 upon gas adsorption confirmed by DOS analysis.
• Limited potential for WF-based sensing was observed.

Conclusions:

• Ni-WSe2 monolayer demonstrates significant potential as a resistance-type gas sensor for CO and HCHO.
• The material's electronic properties are effectively modulated by gas adsorption, enabling sensitive detection.
• This research contributes to the development of advanced nanomaterial-based sensors for monitoring electrical equipment.