Thin film formation at the air-water interface and on solid substrates of soluble axial substituted cis-bis-decanoate tin phthalocyanine

Herein we study thin films of a recent kind of soluble axial substituted cis-bis-decanoate-tin(IV) phthalocyanine (PcSn10) at the air/water interface, which were compressed isothermally and observed with Brewster Angle Microscopy. The air/water interfacial behavior of the films suggests that there are strong interactions among the PcSn10 molecules, which produces multilayers and 3D self-assemblies that prevent the formation of a Langmuir monolayer. Langmuir-Blodgett deposits of these films on both mica (negatively charged) and mild steel (positively charged) surfaces were developed. Information about the morphology of the film was obtained by using atomic force microscopy. We found structural differences in the PcSn10 thin films deposited on both substrates, suggesting that a combination of pi-pi, sigma-pi and Van der Waals interactions are the leading factors for the deposition, and consequently, for the control of supramolecular order. Our findings provide insights in the design of phthalocyanine molecules for the development of highly ordered and reproducible thin films. (C) 2011 Elsevier B.V. All rights reserved.