Variable luminnescence chromaticity and energy transfer in CaZnOS: Pr3+, Mn2+ by ultraviolet and blue excitations

Abstract

Pr3+ and Mn2+ co-doped CaZnOS phosphors are prepared by high-temperature solid state reaction method and the photoluminescence property is investigated systematically. Under 283 ​nm ultraviolet and 447 ​nm blue light excitations, green emission from CaZnOS, Pr3+ and red emission from Mn2+ are obtained and the emission color is modulated from green to yellow and red by adjusting the ratio of Pr3+ to Mn2+ concentration. The photoluminescence process under 283 ​nm and 447 ​nm excitations are dependent on energy transfer from CaZnOS to Pr3+ and Mn2+, as well as energy transfer from Pr3+ to Mn2+. The energy transfer mechanism between Pr3+ and Mn2+ is confirmed to be dipole-quadrupole interaction. Particularly, under 447 ​nm blue excitation, CaZnOS: 1%Pr3+, 3%Mn2+ exhibits bright yellow emission with chromaticity coordinates of (0.372, 0.428) and quantum yields of 46.37%, implying a potential application in blue-chip excited white light emitting diodes (W-LEDs).