Organic Nanostructures with Controllable Morphology Fabricated from Ferrocene–Porphyrin Derivatives: Effect of Metal–Ligand Coordination on the Morphology, Dimensions, and Semiconductor Properties of Self‐Assembled Nanostructures

Two new ferrocene–porphyrin derivatives, namely 5,15-bis(ferrocenyl)-10,20-bis(4-nitrophenyl)porphyrin (1) and its nickel congener 5,15-bis(ferrocenyl)-10,20-bis(4-nitrophenyl)porphyrinatonickel (2) have been designed, synthesized, and characterized. Their self-assembly properties have been comparatively studied by electronic absorption and FTIR spectroscopy, TEM, SEM, XRD, and X-ray photoelectron spectroscopy (XPS). Metal-free 1 self-assembles into nanospheres with diameters in the range of 30–50 nm, depending mainly on intermolecular π–π interactions. In contrast, the coordination of nickel to 1 introduces an additional Ni–O coordination bond between the nitryl group of one molecule of 2 and the nickel center of the neighboring 2 unit, which, in cooperation with the intermolecular π–π interaction, induces the formation of nanobelts (ca. 50–300 μm length, 10–50 nm width) during the self-assembly process of 2.