The molecular arrangement and phase transitions in the vanadyl hexadecafluorophthalocyanine (VOPcF 16 ) thin films grown by physical vapor deposition have been studied using in situ X-ray diffraction, atomic force microscopy, and optical spectroscopy techniques (UV, IR, and Raman). The complete transition from the low-temperature linear cofacial structure to the slipped dimeric one occurs in the temperature range 160−220 °C. This conversion was found to be irreversible upon cooling the VOPcF 16 film back to 20 °C. The structural transformation leads to decrease of the in-plane conductivity of the film by 2 orders of magnitude. According to the polarized Raman spectroscopy measurements, the mean tilt angles between the VOPcF 16 species and the substrate surface were 59 ± 5°and 30 ± 5°in the as-deposited and annealed films, respectively. For the sake of comparison, the structure of the thin films of vanadyl phthalocyanine (VOPc) was also studied. The mean tilt angle between the VOPc species and the substrate surface was found to be 77 ± 5°, in good agreement with existing experimental data (∼70°). All intense bands in the experimental IR and Raman spectra of VOPcF 16 and VOPc were assigned using DFT calculations (B3LYP) and the 15 N isotopic shifts in the vibrational spectra of VOPc.

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In this work, structural features and optical properties of CuPcF 16 films deposited by physical vapour deposition have been investigated. Thin films of two different thicknesses (22 and 198 nm) were characterized by ellipsometry, optical absorption spectroscopy and scanning electron microscopy. Film morphology and optical properties are found to depend on film thickness. Absorption spectra of CuPcF 16 films were compared with those of unsubstituted copper phthalocyanine. The sensor response of CuPcF 16 film to ammonia was studied using surface plasmon resonance measurements. It was stated that strong electron-withdrawing fluorine substituents make this compound sensitive to reducing gases such as NH 3 while unsubstituted CuPc is practically insensitive to this gas.

Nitric oxide (NO) is a highly reactive toxic gas that forms as an intermediate compound during the oxidation of ammonia and is used for the manufacture of hydroxylamine in the chemical industry. Moreover, NO is a signaling molecule in many physiological and pathological processes in mammals, as well as a biomarker indicating the course of inflammatory processes in the respiratory tract. For this reason, the detection of NO both in the gas phase and in the aqueous media is an important task. This review analyzes the state of research over the past ten years in the field of applications of phthalocyanines, porphyrins and their hybrid materials as active layers of chemical sensors for the detection of NO, with a primary focus on chemiresistive and electrochemical ones. The first part of the review is devoted to the study of phthalocyanines and porphyrins, as well as their hybrids for the NO detection in aqueous solutions and biological media. The second part presents an analysis of works describing the latest achievements in the field of studied materials as active layers of sensors for the determination of gaseous NO. It is expected that this review will further increase the interest of researchers who are engaged in the current level of evaluation and selection of modern materials for use in the chemical sensing of nitric oxide.