Fabrication of multiwall carbon nanotube sheet based hydrogen sensor on a stacking multi-layer structure

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Traditional carbon nanotube (CNT) films have limitations in surface area and CNT contact for gas sensing.
• Developing scalable and cost-effective methods for fabricating high-performance CNT-based sensors is crucial for commercialization.

Purpose of the Study:

• To propose a novel, simple method for fabricating hydrogen gas sensors using stacked multiwall carbon nanotube (MWCNT) sheets.
• To investigate the influence of stacking arrangements on the microstructure and CNT interactions for optimized gas sensing.
• To evaluate the performance of functionalized MWCNT sheet-based sensors for hydrogen detection.

Main Methods:

• Fabrication of hydrogen gas sensors by stacking multiwall carbon nanotube (MWCNT) sheets.
• Modification of sensor microstructure and CNT interactions through various layer arrangements.
• Functionalization of MWCNT sheets with palladium (Pd) nanoparticles.
• Gas sensing performance evaluation, including response and response time, at different hydrogen concentrations.

Main Results:

• MWCNT sheets, with their aligned and end-to-end structure, provide superior surface area and CNT contact compared to traditional CNT films.
• A sensor configuration with three stacked MWCNT sheets, functionalized with 3 nm thick palladium (Pd), exhibited optimal gas sensing.
• The optimized sensor achieved a response of 12.31% at 4% H2 with a response time under 200 seconds.

Conclusions:

• The proposed method of stacking MWCNT sheets is a viable approach for producing highly responsive hydrogen gas sensors.
• This technique holds significant potential for the mass production and commercialization of advanced carbon nanotube (CNT)-based gas sensing technologies.
• Optimizing layer arrangement and functionalization is key to maximizing sensor performance.