The photoluminescence of single-phase warm white-light-emitting luminescence using CaSnO₃: Ce³⁺/ Mn⁴⁺/ Dy³⁺ phosphors

In this study, the single-phase warm white-light phosphors were synthesized by the conventional solid-state reaction method. A phosphor composed of CaSnO₃ with the additions of Ce³⁺ (0.5 wt%) and Mn⁴⁺ (0.3 wt%) shows the optimum emission intensity at a correlated color temperature of 3758 K when excited by a 266 nm laser. The luminescence of another CaSnO₃phosphor with the additions of Ce³⁺ (0.5 wt%), Mn⁴⁺ (0.2 wt%), and Dy³⁺ (0.3 wt%) at a CCT of 3998 K is also studied by an excitation at 325 nm. In addition, the spectral overlap between the emission band of Ce³⁺ and the excitation band of Mn⁴⁺ supports the occurrence of the energy transfer from Ce³⁺ to Mn⁴⁺. The speculated energy transfer mechanism between Ce³⁺ and Mn⁴⁺ has been studied and demonstrated to be the exchanged interactions mechanism. Moreover, the concentration quenching was also observed, and the related critical distance of energy transfer evaluated by the concentration quenching methods is about 23.426 Å.