White-light generation and energy transfer in SrZn2(PO4)2:Eu,Mn phosphor for ultraviolet light-emitting diodes

The SrZn2(PO4)2:Eu2+,Mn2+ phosphor shows two emission bands under ultraviolet radiation; the one observed at 416nm is attributed to Eu2+ occupying the Sr2+ sites and the other asymmetric band deconvoluted into two peaks was found to center at 538 and 613nm, which originate from Mn2+ occupying two different Zn2+ sites. The energy transfer from Eu2+ to Mn2+ has been demonstrated to be a resonant type via a dipole-quadrupole mechanism. By utilizing the principle of energy transfer and appropriate tuning of activator contents, we have demonstrated that SrZn2(PO4)2:Eu2+,Mn2+ is potentially useful as an ultraviolet-convertible phosphor for white-light emitting diodes.