Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1331306 | Journal of Solid State Chemistry | 2016 | 6 Pages |
•Synthesis of Sm-doped LaOCl nanoparticles.•DM LaOCl transforms to FM with dilute concentration of Sm doping.•Annealing under H2 atmosphere induces drastic boost in the FM properties.•Saturation magnetization attained 29 memu/g with little doping and hydrogenation.
Pure and Sm-doped lanthanum oxychloride (LaOCl) nanomaterials were synthesized by solvothermal route followed by a subsequent heat treatment process. The objective of the present work is to study and develop conditions required to create stable room-temperature ferromagnetic (RT-FM) properties in LaOCl. To achieve that aim, magnetic samarium Sm3+ ions were used as dopant sources for stable FM properties. Systematic structural, optical, and magnetic properties of undoped and Sm-doped LaOCl samples were investigated as function of post-annealing conditions (temperature and atmosphere). The optical absorption properties were studied by diffuse reflection spectroscopy (DRS). The magnetic measurements reveal that Sm-doped LaOCl nanopowders have partial RT-FM properties due to the doped ions. The variations of magnetic properties with pre-annealing temperature were investigated. Furthermore, the electronic medium of host LaOCl crystalline lattice, which carries the spin-spin (S.S) exchange interaction between localised dopant Sm3+(4f5) spins, was developed by annealing in hydrogen gas (hydrogenation). It was established that annealing in hydrogen atmosphere boosts the RT-FM properties so that the saturation magnetisation could be increased by more than 100%. Physical explanations and discussions were given in this paper. Thus, it was proved that the magnetic properties could be tailored to diamagnetic LaOCl compound by Sm-doping and post treatment under H2 atmosphere. Therefore, LaOCl nanocrystals could be used as a potential candidate for optical phosphor applications with magnetic properties.
Graphical abstractM-H dependence of Sm-doped LaOCl powders. Study the effect of hydrogenation.Figure optionsDownload full-size imageDownload as PowerPoint slide