Processing Additives for Solution-Deposited Films of Zinc Phthalocyanine

Zinc phthalocyanine (ZnPc) receives attention from the industry of optoelectronic materials; so, a much-needed algorithm for uniformly crystalline ZnPc films unimpaired by grain boundaries is under development in the laboratory. Such films are obtainable from solutions based on the binary cyclopentanone-3-dimethylamino-1-propanol system where ketone is a solvent and aminoalcohol acts as a multifunctional processing additive. This work reports on auxiliary additives intended to fully control the film formation: 3-bromopyridine and two ZnPc-based amphiphiles, including a novel one-tailed amphiphile mimicking classic surfactants. The former component, removable from deposited films upon mild annealing, amends the vertical development of the three-dimensional (3D) phase, while the latter ones normalize important physicochemical processes, such as solution spreading and solvent evaporation. Variously shaped ZnPc particles modified with the mentioned additives are prepared by drop-casting and examined by atomic force microscopy with the emphasis on phase-contrast imaging. Applied aspects for the said additives are outlined.