High coercivity SmCo₅ synthesized with assistance of colloidal SiO₂

TY - JOUR

T1 - High coercivity SmCo5 synthesized with assistance of colloidal SiO2

AU - Tang, Hao

AU - Mamakhel, Mohammad Aref Hasen

AU - Christensen, Mogens

N1 - Publisher Copyright: © 2021, The Author(s). Copyright: Copyright 2021 Elsevier B.V., All rights reserved.

PY - 2021/12

Y1 - 2021/12

N2 - SmCo5 is one of the most promising candidates for achieving a hard magnet with a high coercivity. Usually, composition, morphology, and size determine the coercivity of a magnet, however, it is challenging to synthesize phase pure SmCo5 with optimal size and high coercivity. In this paper, we report on the successful synthesis of phase pure SmCo5 with spherical/prolate spheroids shape. Size control is obtained by utilizing colloidal SiO2 as a template preventing aggregation and growth of the precursor. The amount of SiO2 nanoparticles (NPs) in the precursor tunes the average particle size (APS) of the synthesized SmCo5 with particle dimension from 740 to 504 nm. As-prepared pure SmCo5 fine powder obtained from using 2 ml SiO2 suspension possesses an APS of 625 nm and exhibits an excellent coercivity of 2986 kA m−1 (37.5 kOe) without alignment of the particles prior to magnetisation measurements. Comparing with a reference sample prepared without adding any SiO2 NPs, an enhancement of 35% of the coercivity was achieved. The improvement is due to phase purity, stable single-domain (SSD) size, and shape anisotropy originating from the prolate spheroid particles.

AB - SmCo5 is one of the most promising candidates for achieving a hard magnet with a high coercivity. Usually, composition, morphology, and size determine the coercivity of a magnet, however, it is challenging to synthesize phase pure SmCo5 with optimal size and high coercivity. In this paper, we report on the successful synthesis of phase pure SmCo5 with spherical/prolate spheroids shape. Size control is obtained by utilizing colloidal SiO2 as a template preventing aggregation and growth of the precursor. The amount of SiO2 nanoparticles (NPs) in the precursor tunes the average particle size (APS) of the synthesized SmCo5 with particle dimension from 740 to 504 nm. As-prepared pure SmCo5 fine powder obtained from using 2 ml SiO2 suspension possesses an APS of 625 nm and exhibits an excellent coercivity of 2986 kA m−1 (37.5 kOe) without alignment of the particles prior to magnetisation measurements. Comparing with a reference sample prepared without adding any SiO2 NPs, an enhancement of 35% of the coercivity was achieved. The improvement is due to phase purity, stable single-domain (SSD) size, and shape anisotropy originating from the prolate spheroid particles.

UR - http://www.scopus.com/inward/record.url?scp=85101771730&partnerID=8YFLogxK

U2 - 10.1038/s41598-021-83826-5

DO - 10.1038/s41598-021-83826-5

M3 - Journal article

C2 - 33633181

AN - SCOPUS:85101771730

SN - 2045-2322

VL - 11

JO - Scientific Reports

JF - Scientific Reports

M1 - 4682

ER -