Highly selective and sensitive methanol gas sensor based on molecular imprinted silver-doped LaFeO₃ core-shell and...

Area of Science:

• Materials Science
• Chemical Sensing
• Nanotechnology

Background:

• Developing selective and sensitive gas sensors is crucial for environmental monitoring and safety.
• Molecularly imprinted polymers (MIPs) offer tailored recognition sites for specific analytes.
• LaFeO3-based materials are explored for their catalytic and sensing properties.

Purpose of the Study:

• To synthesize and characterize silver-doped LaFeO3 molecularly imprinted polymers (SLMIPs).
• To evaluate the gas-sensing performance of SLMIPs with cage and core-shell structures for methanol detection.
• To investigate the sensing mechanisms and selectivity of the developed materials.

Main Methods:

• Sol-gel method combined with molecularly imprinted technology for precursor synthesis.
• Hydrothermal synthesis and templating with carbon spheres to create SLMIPs cage and core-shell structures.
• Gas sensing measurements to assess response, selectivity, and operating temperature.

Main Results:

• SLMIPs cage and core-shell structures were successfully synthesized.
• Both SLMIPs structures demonstrated significant response and selectivity towards methanol gas.
• Optimal working temperatures were 215 °C for SLM-cage and 195 °C for SLM-core-shell.
• Fast response and recovery times were observed for methanol detection (e.g., 42s response, 57s recovery for SLM-core-shell at 5 ppm).
• Low responses to other gases like ethanol, ammonia, benzene, acetone, and toluene were confirmed.

Conclusions:

• Silver-doped LaFeO3 molecularly imprinted polymers (SLMIPs) are effective materials for methanol gas sensing.
• The cage and core-shell structures exhibit high sensitivity and selectivity for methanol.
• These SLMIPs show potential for developing practical and reliable methanol detectors.