Chemical synthesis and characterization of rare earth - transition metal magnetic nanoparticles

This master thesis investigates the chemical synthesis and characterization of rare-earth – transition-metal magnetic nanoparticles, focusing on the Sm-Co and Ce-Co systems. Both systems crystallize in the Ca〖Cu〗_5 - type hexagonal structure and exhibit strong magnetic anisotropy and high Curie temperatures, making them ideal candidates for permanent magnet applications. The work explores a bottom-up chemical synthesis approach, adapted from previously reported SmCo₅ methods, and applies it to synthesize Ce〖Co〗_5 and Cu-doped Ce〖Co〗_5 nanoparticles. The synthesis was carried out through a co-precipitation method, followed by calciothermic reduction and annealing under various atmospheres (Forming gas and Argon). Structural and morphological characterization was performed using XRD, TEM, SEM, and EDX, while magnetic properties were assessed through Vibrating Sample Magnetometry (VSM). The results demonstrate that the annealing environment and quenching conditions critically determine phase purity and magnetic performance. Successful synthesis of Ce〖Co〗_5 was achieved under sealed argon and rapid quenching conditions, yielding ferromagnetic microparticles with improved coercivity. Although Cu doping did not enhance magnetization due to limited incorporation, the study provides valuable insight into optimizing synthesis parameters for phase-pure Ce〖Co〗_5. Overall, this research establishes Ce〖Co〗_5 as a cost-effective alternative to Sm〖Co〗_5 for permanent magnet applications.