Synthesis and luminescence properties of green phosphors Ca6Sr4(Si2O7)3Cl2:Eu2+ for white light emitting diodes

► Ca6Sr4(Si2O7)3Cl2:Eu2+ phosphor was synthesized by solid-state reactions. ► This phosphor can be effectively excited by ultraviolet light from 320 to 420 nm. ► It exhibits a strong and broad band green emission excited at 360 nm. ► Dipole-dipole interaction is the major mechanism of concentration quenching of Eu2+. ► The phosphor is a promising green component for NUV InGaN-based white LED.