The role of Co2+cation addition in enhancing the AC heat induction power of (CoxMn1-x)Fe2O4superparamagnetic nanoparticles

Jie Wang; Hyungsub Kim; HyeongJoo Seo; Satoshi Ota; Chun-Yeol You; Yasushi Takemura; Seongtae Bae

doi:10.1088/1361-6528/ac8c4b

The role of Co²⁺cation addition in enhancing the AC heat induction power of (Co_xMn_1-x)Fe₂O₄superparamagnetic nanoparticles

Nanotechnology. 2022 Sep 9;33(48). doi: 10.1088/1361-6528/ac8c4b.

Authors

Jie Wang¹, Hyungsub Kim¹, HyeongJoo Seo², Satoshi Ota³, Chun-Yeol You², Yasushi Takemura⁴, Seongtae Bae¹

Affiliations

¹ Nanobiomagnetics and Bioelectronics Laboratory (NB2L), Department of Electrical Engineering, University of South Carolina, Columbia, SC, 29208, United States of America.
² Department of Emerging Materials Science, Daegu Gyeongbuk Institute of Science & Technology, Daegu, 42988, Republic of Korea.
³ Department of Electrical and Electronic Engineering, Shizuoka University, Hamamatsu 432-8561, Japan.
⁴ Department of Electrical and Computer Engineering, Yokohama National University, Yokohama, 240-8501, Japan.

PMID: 36001950
DOI: 10.1088/1361-6528/ac8c4b

Abstract

The physical role of magnetically semi-hard Co²⁺cation addition in enhancing the AC heat induction temperature (T_AC) or specific loss power (SLP) of solid (Co_xMn_1-x)Fe₂O₄superparamagnetic iron oxide nanoparticles (SPIONPs) was systematically investigated at the biologically safe and physiologically tolerable range ofH_AC(H_AC,safe= 1.12 × 10⁹A m^-1s^-1,f_appl= 100 kHz,H_appl= 140 Oe (11.2 A m^-1)) to demonstrate which physical parameter would be the most critical and dominant in enhancing theT_AC(SLP) of SPIONPs. According to the experimentally and theoretically analyzed results, it was clearly demonstrated that the enhancement of magnetic anisotropy (K_u)-dependent AC magnetic softness including the Néel relaxation time constantτ_N(≈τ_eff, effective relaxation time constant), and its dependent out-of-phase magnetic susceptibilityχ″primarily caused by the Co²⁺cation addition is the most dominant parameter to enhance theT_AC(SLP). This clarified result strongly suggests that the development of new design and synthesis methods enabling to significantly enhance theK_uby improving the crystalline anisotropy, shape anisotropy, stress (magnetoelastic) anisotropy, thermally-induced anisotropy, and exchange anisotropy is the most critical to enhance theT_AC(SLP) of SPIONPs at theH_AC,safe(particularly at the lowerf_appl< 120 kHz) for clinically safe magnetic nanoparticle hyperthermia.

Keywords: AC heat induction power; AC magnetic softness; magnetic anisotropy; physical role of Co2+ cation; superparamagnetic nanoparticles.