Tunable luminescence and energy transfer in Ca₃SiO₄Cl_2:Ce³⁺,Li⁺,Mn²⁺,Eu²⁺ phosphors

Abstract

A series of color-tunable Ca SiO Cl (CSC):xCe ,xLi ,yMn ,zEu phosphors with low temperature phase structure was synthesized via the sol-gel method. An energy transfer process from Ce to Mn in CSC:0.01Ce ,0.01Li ,yMn (y = 0.03-0.09) and the mechanism was verified to be an electric dipole-dipole interaction. The Ce and Mn emission intensities were greatly enhanced by co-doping Eu ions into CSC:0.01Ce ,0.01Li ,0.07Mn phosphors due to competitive energy transfers from Eu /Ce to Mn , and Ce to Eu . Under 332 nm excitation, CSC:0.01Ce ,0.01Li+,0.07Mn ,zEu (z = 0.0005-0.002) exhibited tunable emission colors from green to white with coexisting orange, green and violet-blue emissions. These phosphors could have potential application in white light-emitting diodes.

Review of Cholorosilicates as Phosphor Hosts

“…[47] Li et al studied energy transfer from to Eu 2+ and Mn 2+ . [55] Figure 3 includes PL spectra for Ca 3 SiO 4 Cl 2 :Ce 3+ . In the emission (curve c), though two bands are not distinctly seen, it can be conjectured that the broad emission is made up of two bands of equal intensities around 377 and 395 nm.…”