Evaporative Crystallization Synthesis, Tunable and Multimode Luminescence, and Multifunctional Applications of Antimony and Lanthanide Ion-Codoped Cs 2 NaLuCl 6 Double Perovskites

A facile evaporation crystallization method has been utilized to develop the Sb 3+ and Ln 3+ (Er 3+, Ho 3+, Dy 3+, or Sm 3+ )-codoped Cs 2 NaLuCl 6 double perovskite crystals. This synthesis route is simple to operate and merely needs mild reaction conditions, which can be promising for large-scale production. The Sb 3+ and/or Ln 3+ -doped Cs 2 NaLuCl 6 products exhibit high crystallinity and excellent luminescent performance. The emission of the phosphors consists of the self-trapping excitation (STE) of [SbCl 6 ] 3– and f-f transitions of Ln 3+ . A wide-spectrum emission color modulation is achieved by adjusting the doping level of Ln 3+, wherein the effective energy transfer coupling between STE and Ln 3+ is the critical factor governing spectral color manipulation. Notably, the luminescence intensity of STE is significantly enhanced, although energy transfer occurs. This result indicates that the codoping of Ln 3+ can simultaneously introduce new activator ions and enhance the blue emission of STE in Cs 2 NaLuCl 6 double perovskites. Furthermore, the Sb 3+ and Er 3+ /Ho 3+ -codoped Cs 2 NaLuCl 6 materials not only feature down-conversion luminescence and exhibit up-conversion emissions under near-infrared (NIR) excitation but also display dazzling multicolor light under LED chip excitation. These results indicate that the as-synthesized Sb 3+ /Ln 3+ -codoped Cs 2 NaLuCl 6 materials have potential applications in the fields of multimode optical anticounterfeiting and solid-state lighting.