Modulation of Crystallinity and Optical Properties in Composite Materials Combining Iron Oxide Nanoparticles and Dye-Containing Covalent Organic Frameworks

Two series of organic–inorganic composite materials were synthesized through solvothermal imine condensation between diketopyrrolopyrrole dialdehyde DPP-1 and 5,10,15,20-tetrakis(4-aminophenyl)porphyrin (TAPP) in the presence varying amounts either amino- or carboxy-functionalized superparamagnetic iron oxide nanoparticles (FeO). Whereas high FeO loading induced cross-linking inorganic by amorphous polymers, a lower content resulted formation crystalline covalent organic framework domains. All hybrid analyzed magnetization measurements, powder X-ray diffraction, electron microscopy, IR, UV/Vis absorption spectroscopy. Crystallinity, chromophore stacking, visible features are directly correlated to mass fraction components, thus allowing for fine-tuning properties.