Bharadwaj P S J, Kundu Swarup, Kollipara Vijay Sai, Varma Kalidindi B R
Department of Physics, Sri Sathya Sai Institute of Higher Learning, Vidyagiri, Prasanthi Nilayam, Andhra Pradesh, India.
J Phys Condens Matter. 2020 Jan 16;32(3):035810. doi: 10.1088/1361-648X/ab4845. Epub 2019 Sep 26.
Fine powders of Y Sm FeO (x = 0, 0.05, 0.10, 0.15) were synthesized via citrate based sol-gel route. While the as synthesized powders were amorphous, the calcined (900 °C/8 h) powders were confirmed to be polycrystalline by x-ray powder diffraction (XRD) studies. The calcined powders were found to crystallize in an orthorhombic structure associated with the lattice parameters a = 5.59 Å, b = 7.60 Å, c = 5.28 Å. These lattice parameters increased with the increase in Sm content at yttrium sites. The strain that was obtained by the Williamson-Hall method increased with the increase in dopant (Sm) concentration vis-à-vis a decrease in crystallite size. Diffuse reflectance spectroscopic studies suggest an increase in band gap as Sm doping level increased. Significant enhancement in magnetization associated with a decrease in coercive field accompanied by a transition from anti-ferromagnetic to soft ferromagnetic behaviour in Sm doped YFeO were encountered. It is hoped that these materials with the enhanced magnetic properties could be of potential use for multifarious applications.
通过基于柠檬酸盐的溶胶-凝胶法合成了Y Sm FeO（x = 0、0.05、0.10、0.15）的细粉。虽然合成后的粉末是非晶态的，但通过X射线粉末衍射（XRD）研究证实，煅烧（900 °C/8小时）后的粉末是多晶的。发现煅烧后的粉末结晶为正交结构，晶格参数a = 5.59 Å，b = 7.60 Å，c = 5.28 Å。这些晶格参数随着钇位点上Sm含量的增加而增加。通过威廉姆森-霍尔方法获得的应变随着掺杂剂（Sm）浓度的增加而增加，同时晶粒尺寸减小。漫反射光谱研究表明，随着Sm掺杂水平的增加，带隙增大。在Sm掺杂的YFeO中，遇到了与矫顽场降低相关的磁化强度显著增强，同时伴随着从反铁磁到软铁磁行为的转变。希望这些具有增强磁性能的材料可用于多种应用。
