Sharma Priyanka, Jain Anjali, Chatterjee Ratnamala
Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
Nanotechnology. 2021 Dec 17;33(10). doi: 10.1088/1361-6528/ac3e31.
Nanocomposite oxide system of ()CoFeO-(100-)LaFeOwith different weight percent of core-shell structured CoFeO( = 0, 20, 40, 50, 80, 100) and LaFeOwere fabricated, via a two-step sol-gel wet-chemical synthesis technique. The phase formation of the composites was confirmed by x-ray diffraction and the structural parameters of both the phases were attained from the Rietveld refinement results of XRD patterns. The elemental composition and microstructure of the resulting nanocomposites were examined by using energy-dispersive x-ray spectroscopy and high-resolution transmission electron microscopy technique, respectively. The detailed magnetometry studies at 300 K and 5 K reveal that the inter-and intra-phase magnetic interactions affect the saturation magnetization (), remanence magnetization () and coercivity () values of this bi-magnetic system. The remarkable feature of 'pinched magnetic hysteresis loop' was evidenced in the [(50) CoFeO- (50)LaFeO] composite, leading to a lesser magnetic loss factor and better magnetic performance of this sample. The report depicts an improved interfacial exchange coupling at 5 K, for the nanocomposites of core-shell morphology and offers an understanding or explanation of improved magnetic performance for the (50)CoFeO- (50)LaFeOnanocomposite and opens up an important way to design new multiferroic applications in low magnetic fields.
通过两步溶胶-凝胶湿化学合成技术制备了具有不同重量百分比核壳结构CoFeO（ = 0、20、40、50、80、100）和LaFeO的（）CoFeO-（100-）LaFeO纳米复合氧化物体系。通过X射线衍射确认了复合材料的相形成，并从XRD图谱的Rietveld精修结果中获得了两相的结构参数。分别使用能量色散X射线光谱和高分辨率透射电子显微镜技术检查了所得纳米复合材料的元素组成和微观结构。在300 K和5 K下进行的详细磁学研究表明，相间和相内磁相互作用影响该双磁系统的饱和磁化强度（）、剩余磁化强度（）和矫顽力（）值。在[（50）CoFeO-（50）LaFeO]复合材料中证明了“收缩磁滞回线”的显著特征，导致该样品的磁损耗因子较小且磁性能更好。该报告描述了在5 K下，核壳形态的纳米复合材料具有改善的界面交换耦合，并对（50）CoFeO-（50）LaFeO纳米复合材料的磁性能改善提供了理解或解释，并为在低磁场中设计新的多铁性应用开辟了一条重要途径。
