Sureeporn UttiyaSumana KladsomboonOnanong ChamlekWiriya SuwannetTanakorn OsotchanTeerakiat KerdcharoenMartin BrinkmannSirapat PratontepMahidol UniversityInstitut Charles SadronThai Microelectronics Center (TMEC)2018-09-132018-09-132009-01-01Springer Proceedings in Physics. Vol.129, (2009), 211-21518674941093089892-s2.0-84888580926https://repository.li.mahidol.ac.th/handle/123456789/28350© 2009, Springer-Verlag Berlin Heidelberg. Optically active organic gas sensors represent a promising molecular sensing device with low power consumption. We report experimental and computational investigations into the molecular interactions of metal phthalocyanine thin films with alcohol vapor. In the gas-sensing regime, the interactions of zinc phthalocyanine and alcohol molecules were studied by the Density Functional Theory (DFT) calculations, in comparison to the x-ray absorption spectroscopy. The DFT results reveal a reversible charge interaction mechanism between the zinc atom and the oxygen atom in the alcohol OH group, which corresponds to a shift in the x-ray absorption edge of the zinc atom. In the irreversible interaction regime, the effect of saturated alcohol vapor on spin-coated zinc phthalocyanine films was studied by the phase contrast microscopy, the optical absorption spectroscopy, and the transmission electron microscopy. Annealing the spin-coated films in saturated methanol vapor was found to induce an irreversible structural transformation from an amorphous to a crystalline phase, similar to the effect of a thermal annealing process. These crystallization processes of the zinc phthalocyanine films were also found to enhance their stability and alcohol sensing performance.Mahidol UniversityPhysics and AstronomyChapterSCOPUS10.1007/978-3-540-95930-4_35