Metal-Decorated Phthalocyanine Monolayer as a Potential Gas Sensing Material for Phosgene: A First-Principles Study

Area of Science:

• Materials Science
• Environmental Chemistry
• Computational Chemistry

Background:

• Phosgene (COCl2) is a toxic gas requiring sensitive detection for environmental and biological safety.
• Phthalocyanine (Pc) based materials are being investigated for gas sensing applications.

Purpose of the Study:

• To investigate the adsorption performance of phosgene (COCl2) on pristine and metal-decorated phthalocyanine (Pc) monolayers.
• To evaluate the potential of these materials as gas sensors for COCl2 detection.

Main Methods:

• First-principles calculations were employed to study COCl2 adsorption on pristine Pc, CuPc, GaPc, and RuPc.
• Analysis of density of states, charge density difference, and Hirshfeld charge elucidated adsorption mechanisms.

Main Results:

• Physisorption of COCl2 on pristine Pc and CuPc indicates unsuitability for sensing.
• Chemisorption was observed for COCl2 on GaPc (-0.57 eV) and RuPc (-0.50 eV).
• RuPc monolayer exhibited significant conductivity variation upon COCl2 adsorption, demonstrating high sensitivity and fast desorption.

Conclusions:

• Ruthenium-decorated phthalocyanine (RuPc) is a potential candidate for phosgene sensors due to its moderate adsorption strength, high sensitivity, and rapid desorption.
• The findings highlight the importance of metal decoration in enhancing the gas sensing properties of phthalocyanine materials.