Fluorination vs. Chlorination: Effect on the Sensor Response of Tetrasubstituted Zinc Phthalocyanine Films to Ammonia

Chemosensors

Pavel Krasnov¹  Tamara Basova²  Dmitry Bonegardt²  Pavel Popovetskiy²  Darya Klyamer²  Aleksandr Sukhikh² 

[1] International Research Center of Spectroscopy and Quantum Chemistry, Siberian Federal University, 660074 Krasnoyarsk, Russia;Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Lavrentiev Pr., 630090 Novosibirsk, Russia;

关键词: metal phthalocyanines;    chemiresistive sensors;    gas sensors;    thin films;    ammonia halogen substituents;    crystal structure;   

DOI  :  10.3390/chemosensors9060137

来源: DOAJ

【 摘 要 】

In this work, the effect of fluorine and chlorine substituents in tetrasubstituted zinc phthalocyanines, introduced into the non-peripheral (ZnPcR₄-np, R = F, Cl) and peripheral (ZnPcR₄-p, R = F, Cl) positions of macrocycle, on their structure and chemiresistive sensor response to low concentration of ammonia is studied. The structure and morphology of the zinc phthalocyanines films (ZnPcR₄) were investigated by X-ray diffraction and atomic force microscopy methods. To understand different effects of chlorine and fluorine substituents, the strength and nature of the bonding of ammonia and ZnPcHal₄ molecules were studied by quantum chemical simulation. It was shown on the basis of comparative analysis that the sensor response to ammonia was found to increase in the order ZnPcCl₄-np < ZnPcF₄-np < ZnPcF₄-p < ZnPcCl₄-p, which is in good agreement with the values of bonding energy between hydrogen atoms of NH₃ and halogen substituents in the phthalocyanine rings. ZnPcCl₄-p films demonstrate the maximal sensor response to ammonia with the calculated detection limit of 0.01 ppm; however, they are more sensitive to humidity than ZnPcF₄-p films. It was shown that both ZnPcF₄-p and ZnPcCl₄-p and can be used for the selective detection of NH₃ in the presence of carbon dioxide, dichloromethane, acetone, toluene, and ethanol.

【 授权许可】

Unknown