Zhiguo Zhao* and Xue Li*. Hydrothermal Synthesis and Optical Properties of Magneto-Optical Na3FeF6: Tb3+ Octahedral Particles. Materials. 2020, 13, 320. DOI: 10.3390/ma13020320

Sodium iron hexafluoride (Na ₃FeF ₆), as a colorless iron fluoride, is expected to be an ideal host for rare earth ions to realize magneto-optical bi-functionality. Herein, monodispersed terbium ions (Tb ³⁺) doped Na ₃FeF ₆ particles are successfully synthesized by a facile one-pot hydrothermal process. X-ray diffraction (XRD) and Field emission scanning electron microscopy (FESEM) reveal that the Tb ³⁺ doped Na ₃FeF ₆ micro-particles with regular octahedral shape can be assigned to a monoclinic crystal structure (space group P21/c). Under ultraviolet light excitation, the Na ₃FeF ₆:Tb ³⁺ octahedral particles given orange-red light emission originated from the ⁵D ₄→ ⁷F _J transitions of the Tb ³⁺ ions. In addition, the magnetism measurement indicates that Na ₃FeF ₆:Tb ³⁺ octahedral particles are paramagnetic with high magnetization at room temperature. Therefore, the Na ₃FeF ₆:Tb ³⁺ powders may find potential applications in the biomedical field as magnetic-optical bi-functional materials.