Preparation of thin phthalocyanine layers and their structural and absorption properties

Abstract

Phthalocyanines (Pcs) may act as efficient absorbents of photons in the visible region. These structures upon contact with photons from well-defined regions, specifically between 600 and 700 nm, may produce an excited triple state. Its extinction is accompanied by the formation of highly active singlet oxygen species. Its utilization ranges from sensors to selective medical diagnosis tools. In this work we report on preparation of Al and Zn phthalocyanines thin layers of a constant thickness via a method of vacuum sublimation. The produced films were smooth, homogeneous, resistant and well transparent. The films were examined by means of AFM, SEM, profilometry, ellipsometry, Raman spectroscopy and UV–VIS. Special attention was paid to the crystallinity changes with temperature observable by XRD. Light absorption properties of the Pcs films were compared with those recorded in solution (sulphonated Pcs dissolved in water).