Luminescence characteristics of doubly doped KLuS2:Eu, RE (RE = Pr, Sm, Ce)

• We synthesised and characterized KLuS2:Eu2+, RE3+ (RE = Ce, Pr, Sm) compounds.
• We studied the effect of concentration dependence of Eu2+ and RE3+ on CIE coordinates.
• We confirmed the thermal stability of Eu2+ and Sm3+ emission up to 200 °C.
• We evidenced the Eu2+–RE3+ energy transfer in KLuS2 host.
• We discussed the application potential of studied materials as white LED phosphors.

KLuS2 single crystals doped with divalent europium and co-doped with trivalent praseodymium, samarium or cerium were synthesized in the form of crystalline hexagonal platelets as interesting candidates for white LED solid state lighting. Luminescence characteristics in UV/Vis, including radioluminescence, photoluminescence excitation and emission spectra and photoluminescence decays, were measured in the broad concentration and temperature interval revealing presence of thermally stable emission features of both Eu2+ and co-dopants in a single KLuS2 host. Energy transfer from Eu2+ to Pr3+, Sm3+ and Ce3+ is identified. CIE xy-coordinates are used to compare effects of dopants on resulting spectrum. The application potential in white LEDs phosphors is discussed.