Enhancing the Ordering and Coercivity of L1₀ FePt Nanostructures with Bismuth Additives for Applications Ranging from Permanent Magnets to Catalysts

L1₀ highly ordered FePt nanostructures were successfully synthesized following a direct one-step liquid phase chemical approach. The enhanced ordering was achieved with the use of bismuth additives in the reaction mixture. The as-made nanostructures are ferromagnetic, revealing high coercivity without any post annealing processing. The effect of bismuth addition was studied extensively, and the synthesized nanostructures were characterized by a plethora of techniques including TEM, STEM, elemental mapping, XRD, and Mössbauer spectroscopy for the structural and morphological characterization and VSM for the study of magnetic properties. The maximum room temperature coercivity of the directly synthesized FePt nanoalloys is 15.2 kOe, a value which is the highest, to the best of our knowledge, for analogous as-made liquid phase synthesized nanomaterials. The L1₀ FePt nanostructures with bismuth additives have promising applications in permanent magnets, in ultrahigh density recording media, and as highly durable Pt-based catalysis.