Atypical Film-Forming Behavior of Soluble Tetra-3-Nitro-Substituted Copper Phthalocyanine

Amine-assisted solubilization of unsubstituted zinc phthalocyanine for film deposition purposes

Typical zinc phthalocyanines (ZnPc) exhibit poor solubility in common solvents and, hence, are processed into thin films mostly from the vapor phase. The present work discloses how these limitations can be effectively overcome. Specifically, highly concentrated molecular solutions of unsubstituted ZnPc are prepared by combining a weakly structured ZnPc polymorph with binary liquid systems composed of a π-accepting solvent and a simple nitrogenous base, such as ammonia or tertiary aliphatic amine. The amine-assisted solubilization of ZnPc is rationalized by quantitative analysis of optical spectra and electrostatic potential maps of the dye molecule. A volatile aminoalcohol is proposed in order to rationally modify the habit of ZnPc crystallites and concurrently to produce uniform deposition of the crystallites by drop-casting the dye solutions onto a glass substrate. Finally, a versatile algorithm for wet-processed ZnPc films is declared.

Wet-processing of unsubstituted zinc phthalocyanine into polycrystalline films is mastered.

Formation and Characterization of Air-Stable Lipid Bilayer Membranes Incorporated with Phthalocyanine Molecules

Bilayer lipid membranes (BLMs) are used as basic frameworks for biosensors and biohybrid devices due to their unique properties, which include ultrathin thickness, ultrahigh resistivity, and self-assembling ability. However, BLMs can only form and maintain their structure in aqueous environments, which pose significant limitations to their use. In this work, we report on the formation of highly uniform hybrid BLMs at a water/air interface through self-assembly by simply doping the BLMs with a functional organic molecule, copper(II) 2,9,16,23-tetra-tert-butyl-29H,31H-phthalocyanine (CuPc). By transferring the membrane onto substrates, we were able to produce stable hybrid BLMs under anhydrous conditions. Atomic force microscopy and X-ray diffraction measurements confirmed that the hybrid membranes were composed of single, highly uniform BLMs or stacks of BLMs. Fluorescence resonance energy transfer measurements indicated that the CuPc molecules were located between the hydrophobic tails of lipid molecules, forming a sandwich structure in the hybrid membranes. The hybrid BLMs fabricated by this method substantially expand the range of applications of BLMs to solid-state devices.