Luminescence and Energy Transfer Mechanism in Ca[sub 10]K(PO[sub 4])[sub 7]:Eu[sup 2+], Mn[sup 2+] Phosphor

Abstract

A series of Ca10K(PO4)7:Eu2+,Mn2+Ca10K(PO4)7:Eu2+,Mn2+ (CKP:Eu2+,Mn2+)(CKP:Eu2+,Mn2+) phosphors was synthesized by solid-state reaction. Under an optimal excitation of 347 nm, we have observed a blue emission band at 467 nm and a red emission band at 634 nm, which resulted from Eu2+Eu2+ and Mn2+Mn2+ , respectively. The energy transfer from Eu2+Eu2+ to Mn2+Mn2+ in CKP host matrix is of a resonant type via a dipole–quadrupole mechanism. By properly varying the ratio of Eu/Mn, the emission hue can be tuned from blue (0.18,0.21), to white (0.30,0.24), and finally to red (0.35,0.24). The intensity of composition-optimized CKP:Eu2+CKP:Eu2+ is about 30% of BaMgA110O17:Eu2+BaMgA110O17:Eu2+ . The measurement of thermal quenching for CKP:Eu2+,Mn2+CKP:Eu2+,Mn2+ and yttrium aluminum garnet:Ce3+yttrium aluminum garnet:Ce3+ was also compared and investigated in the study. The (CKP:Eu2+,Mn2+)(CKP:Eu2+,Mn2+) phosphor may serve as a candidate for UV light-emitting diode application.