Wireless Hand-Held Device Based on Polylactic Acid-Protected, Highly Stable, CTAB-Functionalized Phosphorene for CO₂...

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Phosphorene, a 2D material, offers unique properties but suffers from environmental instability.
• Developing stable phosphorene-based sensors is crucial for practical applications.
• Existing gas sensors often lack sensitivity, selectivity, or long-term stability.

Purpose of the Study:

• To develop an effective liquid exfoliation method for stable few-layer phosphorene (FLP).
• To investigate the gas-sensing properties of CTAB-grafted phosphorene (P-CTAB) for carbon dioxide (CO2) detection.
• To create a portable, stable, and sensitive CO2 gas sensor using P-CTAB and a polylactic acid (PLA) membrane.

Main Methods:

• Liquid exfoliation of bulk black phosphorus (BP) using cetyltrimethylammonium bromide (CTAB) surfactant.
• Fabrication of a P-CTAB sensor and a P-CTAB/polylactic acid (PLA) based Arduino device.
• Characterization of P-CTAB stability and evaluation of CO2 gas sensing performance, including sensitivity and response to relative humidity.

Main Results:

• Successfully exfoliated and stabilized few-layer phosphorene (FLP) using CTAB.
• CTAB-grafted phosphorene (P-CTAB) exhibited a dynamic sensing response increase with varying relative humidity.
• The P-CTAB sensor showed high sensitivity (0.0356 ppm^-1) towards CO2.
• The P-CTAB/PLA device demonstrated trace-level CO2 detection with negligible drift over 30 days.

Conclusions:

• CTAB effectively stabilizes phosphorene, enabling its use in gas sensing applications.
• CTAB-grafted phosphorene presents a novel, ultrasensitive, and selective material for CO2 detection.
• The developed portable device offers a stable and reliable solution for environmental CO2 monitoring.