Smari Mourad, Moisiuc Monica Viorica, Al-Haik Mohammad Y, Astefanoaei Iordana, Stancu Alexandru, Shelkovyi Fedor, Gimaev Radel, Piashova Julia, Zverev Vladimir, Haik Yousef
Center for Advanced Materials Research, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah P.O. Box 27272, United Arab Emirates.
Faculty of Physics, Alexandru Ioan Cuza University of Iasi, 700506 Iasi, Romania.
Nanomaterials (Basel). 2025 Apr 23;15(9):642. doi: 10.3390/nano15090642.
The use of perovskite manganite nanoparticles in magnetic hyperthermia has attracted significant attention due to their tunable magnetic properties and high specific absorption rate (SAR). In this work, we present a combined experimental and theoretical investigation of the frequency- and amplitude-dependent magnetic heating behavior of LaSrMnO (LSMO) and Dy-doped LaDySrMnO (DLSMO) nanoparticles. The nanoparticles were synthesized via the sol-gel method and characterized by XRD and SEM, while SAR values were experimentally evaluated under varying magnetic field strengths (60-120 Oe) and frequencies (150-300 kHz). In parallel, theoretical modeling based on Néel and Brownian relaxation mechanisms was employed to predict SAR behavior as a function of particle size, magnetic anisotropy, and fluid viscosity. The results reveal that Dy doping enhances magnetic anisotropy, which modifies the relaxation dynamics and leads to a reduction in SAR. The model identifies the optimal nanoparticle size (~18-20 nm) and ferrofluid viscosity to maximize heating efficiency. This combined approach provides a comprehensive framework for designing and optimizing perovskite-based nanoparticles for magnetic hyperthermia applications.
钙钛矿锰氧化物纳米颗粒在磁热疗中的应用因其可调谐的磁性能和高比吸收率（SAR）而备受关注。在这项工作中，我们对LaSrMnO（LSMO）和Dy掺杂的LaDySrMnO（DLSMO）纳米颗粒的频率和幅度依赖性磁热行为进行了实验和理论相结合的研究。通过溶胶-凝胶法合成了纳米颗粒，并用XRD和SEM对其进行了表征，同时在不同磁场强度（60 - 120 Oe）和频率（150 - 300 kHz）下通过实验评估了SAR值。同时，基于奈尔和布朗弛豫机制的理论模型被用于预测SAR行为与颗粒尺寸、磁各向异性和流体粘度的函数关系。结果表明，Dy掺杂增强了磁各向异性，这改变了弛豫动力学并导致SAR降低。该模型确定了最佳纳米颗粒尺寸（约18 - 20 nm）和铁磁流体粘度，以最大化加热效率。这种综合方法为设计和优化用于磁热疗应用的钙钛矿基纳米颗粒提供了一个全面的框架。
