Low-Platinum-Content Exchange-Coupled CoPt Nanoalloys with Enhanced Magnetic Properties

Autor: Georgia Basina, Vasileios Alexandrakis, Ioannis Panagiotopoulos, Dimitrios Niarchos, Eamonn Devlin, Margarit Gjoka, George C. Hadjipanayis, Vasileios Tzitzios
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: Nanomaterials, Vol 14, Iss 6, p 482 (2024)
Druh dokumentu: article
ISSN: 2079-4991
DOI: 10.3390/nano14060482
Popis: Bimetallic colloidal CoPt nanoalloys with low platinum content were successfully synthesized following a modified polyol approach. Powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) studies were performed to estimate the crystal structure, morphology, and surface functionalization of the colloids, respectively, while the room-temperature magnetic properties were measured using a vibrating sample magnetometer (VSM). The particles exhibit excellent uniformity, with a narrow size distribution, and display strong room-temperature hysteretic ferromagnetic behavior even in the as-made form. Upon annealing at elevated temperatures, progressive formation and co-existence of exchange coupled, of both chemically ordered and disordered phases significantly enhanced the room-temperature coercivity.
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