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We synthesized BaAl12O19:Eu2+ phosphors by the molten salt flux method at the relatively low temperature. The phase and luminescent properties of the synthesized phosphors were investigated. To investigate the influence of synthesis temperature on the phase formation of phosphors, different synthesis temperatures were carried out in the work. With the increasing synthesis temperature, the phase of product transfers from BaAl2O4 to BaAl12O19. And the emission band shifts to shorter wavelength due to the phase transition with the increasing synthesis temperature. The reason of blue shift is revealed by the analysis of crystal field splitting. The synthesized BaAl12O19:Eu2+ phosphors also show high color purity and excellently thermal stability.

Room temperature ferromagnetic Cu-doped LiNbO3 thin films with Cu contents of 2–8 at.% were deposited by RF-magnetron sputtering. X-ray absorption spectroscopy together with multiple-scattering ab initio theoretical calculations at Cu K-edge revealed the incorporation of Cu ions into Nb sites in the LiNbO3 host lattice with divalent valence state. The detailed local structural analysis also confirmed that oxygen vacancies are present in the nearest coordination shell of the Cu atoms. The activated ferromagnetism in the Cu-doped LiNbO3 is intrinsic and probably originates from indirect interactions between the oxygen vacancies and dopant ions, which forms bound magnetic polarons and overlapping polaron orbitals, resulting in stable ferromagnetic ordering. These results present a practical method of triggering room temperature ferromagnetism in non-magnetic Cu element doped LiNbO3 systems with oxygen defects, which helps elucidate the origin of ferromagnetism in perovskite ferroelectric oxides.

Mn4+ and/or Dy3+ doped Ca2LaTaO6 phosphors were prepared by a molten salt process. The phase and photoluminescence characteristics of the prepared phosphors were researched. The XRD patterns of the prepared phosphors coincide with the normative XRD pattern of Ca2LaTaO6, demonstrating that Mn4+ and Dy3+ ions doped into Ca2LaTaO6 host and formed solid solution with a single phase. For Dy3+ single doped Ca2LaTaO6 phosphors, they exhibit photoluminescence bands corresponding to 4F9/2 → 6H15/2, 6H13/2 and 6H11/2 transitions of Dy3+ while they are excited at 375 nm. For Mn4+ single doped Ca2LaTaO6 phosphors, they exhibit photoluminescence bands corresponding to 2Eg → 4A2g transitions of Mn4+ while they are excited at 321 nm Ca2LaTaO6:Mn4+/Dy3+ phosphors exhibit photoluminescence bands corresponding to transitions of Dy3+ and Mn4+ while they are excited at 375 nm. In Mn4+/Dy3+ codoped Ca2LaTaO6 phosphors, energy transfer from Dy3+ to Mn4+ occurred, which leads to the enhancements of Mn4+ photoluminescence.