Ordered mesoporous NiO with thin pore walls and its enhanced sensing performance for formaldehyde

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Formaldehyde (HCHO) is a common indoor air pollutant with significant health implications.
• Developing highly sensitive and selective gas sensors for HCHO detection is crucial for environmental monitoring and safety.
• Nickel oxide (NiO) is a promising semiconductor material for gas sensing applications.

Purpose of the Study:

• To synthesize ordered mesoporous nickel oxide (NiO) materials using a nanocasting route.
• To investigate the effect of textural parameters (surface area, pore size, pore wall thickness) on HCHO sensing performance.
• To develop a high-response formaldehyde gas sensor based on mesoporous NiO.

Main Methods:

• Nanocasting synthesis using mesoporous silica as a hard template.
• Fabrication of ordered mesoporous NiO with varied textural properties.
• Gas sensing measurements for formaldehyde (HCHO) at different concentrations.
• Correlation analysis between material structure and sensing performance.

Main Results:

• Ordered mesoporous NiO exhibited significantly higher response to HCHO compared to bulk NiO.
• Enhanced sensing performance was observed even at low HCHO concentration levels.
• Larger specific surface area, larger pore size, and thinner pore walls positively correlated with improved HCHO sensing.

Conclusions:

• Ordered mesoporous NiO is a superior material for formaldehyde gas sensing.
• The nanocasting method provides control over NiO structure for optimized sensor performance.
• Tailoring the pore structure of NiO is key to achieving high-sensitivity HCHO detection.