Effect of Cu/C ratio and pyrolysis conditions on the magnetic behavior of copper porphyrin and phthalocyanine.

This study examines how the copper-to-carbon ratio, temperature, and pyrolysis duration affect the magnetic properties of copper-based porphyrin (CuTPP) and phthalocyanine (CuPc) nanocomposites. Key magnetic parameters—coercivity, remanence, and saturation magnetization—were measured using vibrating sample magnetometry under varying synthesis conditions and corbon composition. Increasing the Cu/C ratio enhanced overall magnetization, indicating stronger ferromagnetic ordering; however, higher copper loading also broadened hysteresis loops, suggesting increased coercivity and partial aggregation of metallic Cu nanoparticles within the carbon framework. Pyrolysis time (10–20 min at 850 °C) further influenced particle growth and domain coupling. Structural and morphological analyses were performed via X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM-STEM), revealing changes in crystallinity and nanoparticle distribution. These results highlight how controlled pyrolysis of organometallic precursors enables tuning of magnetic behavior, offering a pathway to engineer next-generation ferromagnetic and giant paramagnetic nanocomposites with customizable properties for advanced technological applications.