Metal phthalocyanines (MPcs) are macrocyclic compounds with a highly conjugated 18-π electronic system with a central chelated metal ion. MPcs can be functionalized in the peripheral (ligand) and axial (metal) positions, which gives them the ability to change their physical, chemical, and electronic properties. Thin films based on MPcs are a fast-growing research area due to their ability to form highly ordered thin films with different surface morphologies, depending on the molecular structure and corresponding packing. These characteristics allow the development of various thin films devices such as gas sensors, thin-film transistors, and light-emitting diodes. This research aims to analyze the surface and morphology of different substrates (aluminum, quartz, and silicon wafer) covered with a unique cobalt phthalocyanine (CoPc). Our CoPc is tetrasubstituted with a 3,5-<i>bis</i>(trifluoromethyl)phenyl group in the peripheral position, synthesized through a solid-state reaction. We have been able to confirm the formation of the CoPc macrocycle through ultraviolet-visible absorption by the presence of the two strong absorption bands characteristic in MPcs, one in the UV region of (280-350nm) and another in the visible region (550-750nm). We will discuss the characterization of our CoPc using spectroscopy techniques such as FT-IR and NMR. The growth of thin films through physical vapor deposition (PVD) has been achieved by taking advantage of the thermal stability of the MPcs to sublime and deposit it on the surface of the target substrate. Using the PVD technique, we have grown nanorods using our CoPc on the aluminum substrate with lengths ranging from 1-7µm. For the characterization of the films, we will present surface analysis techniques such as AFM, SEM, and XRD. As a result, we will show the different morphologies and grain sizes that exhibit a dependence on surfaces temperature, substrate surface properties, and molecule–surface interactions.

Surface analysis of peripheral tetrasubstituted cobalt phthalocyanine thin films

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.