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Title: Tailoring the Magnetic and Hyperthermic Properties of Biphase Iron Oxide Nanocubes through Post-Annealing
Tailoring the magnetic properties of iron oxide nanosystems is essential to expanding their biomedical applications. In this study, 34 nm iron oxide nanocubes with two phases consisting of Fe3O4 and α-Fe2O3 were annealed for 2 h in the presence of O2, N2, He, and Ar to tune the respective phase volume fractions and control their magnetic properties. X-ray diffraction and magnetic measurements were carried out post-treatment to evaluate changes in the treated samples compared to the as-prepared samples, showing an enhancement of the α-Fe2O3 phase in the samples annealed with O2 while the others indicated a Fe3O4 enhancement. Furthermore, the latter samples indicated enhancements in crystallinity and saturation magnetization, while coercivity enhancements were the most significant in samples annealed with O2, resulting in the highest specific absorption rates (of up to 1000 W/g) in all the applied fields of 800, 600, and 400 Oe in agar during magnetic hyperthermia measurements. The general enhancement of the specific absorption rate post-annealing underscores the importance of the annealing atmosphere in the enhancement of the magnetic and structural properties of nanostructures.  more » « less
Award ID(s):
2327667
PAR ID:
10526093
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
MDPI
Date Published:
Journal Name:
Crystals
Volume:
14
Issue:
6
ISSN:
2073-4352
Page Range / eLocation ID:
519
Subject(s) / Keyword(s):
iron oxide nanocubes phase tunability magnetic hyperthermia biomedicine
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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