Proposals for gas-detection improvement of the FeMPc monolayer towards ethylene and formaldehyde by using bimetallic...

Development and fabrication of a novel gas sensor with superb performance are crucial for enabling real-time monitoring of ethylene (C₂H₄) and formaldehyde (H₂CO) emissions from industrial manufacture. Herein, first-principles calculations and AIMD simulations were carried out to investigate the effect of the Fe-M dimer on the adsorption of C₂H₄ and H₂CO on metal dimer phthalocyanine (FeMPc, M = Ti-Zn) monolayers, and the electronic structures and sensing properties of the above adsorption systems were systematically discussed. The results show that the FeMPc (M = Ti, V, Cr, Mn) monolayers interact with C₂H₄ and H₂CO by chemisorption except for the FeMnPc/H₂CO system, while the other adsorption systems are all characterized by physisorption. Interestingly, the adsorption strength of C₂H₄ and H₂CO can be effectively regulated by the bimetallic synergy of the Fe-M dimer. Moreover, the FeCrPc and FeMnPc monolayers exhibit excellent sensitivity towards C₂H₄ and H₂CO, and have short recovery time (4.69 ms-2.31 s) for these gases at room temperature due to the effective surface diffusion at 300 K. Consequently, the FeCrPc and FeMnPc materials can be utilized as high-performance, reusable gas sensors for detecting C₂H₄ and H₂CO, and have promising applications in monitoring the release of ethylene and formaldehyde from industrial processes.