A novel single-phase Ca3Gd2Si3O12:Dy3+, Sm3+ phosphor exhibiting high thermal stability for solid-state lighting applications

In order to obtain efficient single-phase co-doped phosphors with excellent luminescence properties under near-ultraviolet excitation, Ca 3 Gd 2 Si 3 O 12 : x Dy 3+ (CGSO: x Dy 3+ ) and Ca 3 Gd 2 Si 3 O 12 :0.08Dy 3+ , y Sm 3+ (CGSO:0.08Dy 3+ , y Sm 3+ ) phosphors were effectively manufactured using the classical high-temperature solid-phase method. The phase structure, morphology and XPS test results of the phosphor all show that the Ca 3 Gd 2 Si 3 O 12 (CGSO) material has been successfully synthesized, and Dy 3+ and Sm 3+ ions have been successfully doped into the matrix lattice. Under 362 nm illumination, the PL spectra of CGSO:0.08Dy 3+ , y Sm 3+ phosphor revealed that the typical peak intensity of Dy 3+ ions declined as the amount of Sm 3+ ions increased, whereas the distinctive peak intensity of Sm 3+ ions achieved its maximum at y  = 0.07. As Sm 3+ doping grows larger, the fluorescence lifetime shortens, signifying the occurrence of transferring energy among Dy 3+ and Sm 3+ ions, with a maximum efficiency of 81 % being attained. The Ca 3 Gd 2 Si 3 O 12 :0.08Dy 3+ , y Sm 3+ phosphor demonstrates a commendable thermal stability of 90.17 %, with adjustments to the Sm 3+ concentration revealing the potential to yield warm white light, as evidenced by both CIE chromaticity coordinates and CCT measurements. In addition, compared with the phosphor containing only Dy 3+ , the LED assembled with CGSO:0.08Dy 3+ , y Sm 3+ phosphor containing Sm 3+ ions and 365 nm LED chip emits warmer white light with lower color temperature, which confirms the application value of CGSO:0.08Dy 3+ , y Sm 3+ phosphor in the domain of solid-state lighting.