Development of a single-phased Ca3SnSi2O9: Bi3+, Dy3+, Eu3+ phosphor with tri-colors for white light-emitting diodes

The bright blue emission at 420 nm, originating from the charge transfer transition of the self-activated SnO6 octahedron, was observed in Ca3SnSi2O9 host matrix. Bi3+, Dy3+ and Eu3+ exhibited their characteristic emission under ultraviolet excitation when these activators were doped into Ca3SnSi2O9, respectively. The emission intensity located at the blue-yellow and red region of Dy3+ and Eu3+ could be further improved when Bi3+ was co-doped in Dy3+, Eu3+ doped Ca3SnSi2O9. Furthermore, a tunable color emission, especially the white light, was realized in Ca3SnSi2O9: Bi3+, Dy3+, Eu3+ phosphors by adjusting the relative concentration of the activators. It demonstrates that Bi3+, Dy3+, Eu3+ codoped Ca3SnSi2O9 could potentially be used as a tricolor phosphor for the fabrication of phosphor-converted light emitting diodes (pc-LED).