Pathak Saurabh, Verma Rajni, Singhal Sakshi, Chaturvedi Raghav, Kumar Prashant, Sharma Pragati, Pant R P, Wang Xu
School of Engineering, RMIT University, Melbourne, VIC, Australia.
Department of Mechanical Engineering, The University of Melbourne, Parkville, VIC, 3010, Australia.
Sci Rep. 2021 Feb 15;11(1):3799. doi: 10.1038/s41598-021-83394-8.
Microwave spin resonance behavior of the FeO surface decorated ZnO nanocomposites (FZNC) has been investigated by ferromagnetic resonance (FMR). Modified hydrothermal method has been adopted to fabricate FZNC samples with FeO nanoparticles chains were used as seeds in the uniform magnetic field to decorate them on the surface of the ZnO nanoparticles in a unique configuration. Spin dynamics investigation confirms the transition of ZnO from diamagnetic to ferromagnetic as the sharp FMR spectra converts to the broad spectra with FeO nanoparticles incorporation. A single broad FMR spectra confirms that no isolated Fe or Zn ions exist which is also in agreement with XRD confirming suitable composite formation. Further, the increase in FeO concentration leads to decrease in g-value which is resulting from the internal field enhancement due to magnetic ordering. Also, various spin resonance parameters were calculated for the FZNC which provides a detail information about the magnetic ordering, exchange coupling and anisotropy. Elemental analysis confirms the presence of Fe and Zn simultaneously and transmission electron microscopy (TEM) image show the presence of FeO on the grain boundaries of ZnO which has been confirmed by taking high-resolution TEM and electron diffraction patterns on both sides of the interface. These unique structural configuration of the FZNC has tremendous potential in various magneto-optoelectronic, spintronics and electro-chemical applications.
通过铁磁共振（FMR）研究了FeO表面修饰的ZnO纳米复合材料（FZNC）的微波自旋共振行为。采用改进的水热法制备FZNC样品，以FeO纳米颗粒链为种子，在均匀磁场中以独特的构型将它们装饰在ZnO纳米颗粒表面。自旋动力学研究证实，随着FeO纳米颗粒的掺入，尖锐的FMR光谱转变为宽光谱，ZnO从抗磁性转变为铁磁性。单一的宽FMR光谱证实不存在孤立的Fe或Zn离子，这也与XRD一致，证实形成了合适的复合材料。此外，FeO浓度的增加导致g值降低，这是由于磁有序导致内场增强所致。还计算了FZNC的各种自旋共振参数，这些参数提供了有关磁有序、交换耦合和各向异性的详细信息。元素分析证实同时存在Fe和Zn，透射电子显微镜（TEM）图像显示在ZnO的晶界上存在FeO，这已通过在界面两侧拍摄高分辨率TEM和电子衍射图得到证实。FZNC的这些独特结构构型在各种磁光电子、自旋电子学和电化学应用中具有巨大潜力。
