Tunable multicolor luminescent properties of Ca8ZnLa(PO4)7:Ce3+, Mn2+ phosphor via efficient energy transfer

A series of single doped (Ce 3+ ) and co-doped (Ce 3+ and Mn 2+ ) Ca 8 ZnLa(PO 4 ) 7 (CZLP) phosphors are synthesized in air by using the solid-state reaction method. The crystal structure, morphology, and luminescence properties of the samples are investigated. The blue emission of CZLP:Ce 3+ phosphors is observed in the range of 325–450 nm when they are excited by 315 nm ultraviolet (UV) light, and the optimal Ce 3+ concentration is about 8 mol%. With excitation at 315 nm, a tunable color emission of CZLP:8%Ce 3+ , yMn 2+ phosphors from blue to red is displayed when Mn 2+ concentration is changed from 0 to 12 mol%, and the corresponding chromaticity coordinates are varied from (0.1635, 0.0118) to (0.5885, 0.2829). The spectral propertires and lifetimes confirm the energy transfer (ET) process from Ce 3+ to Mn 2+ ions in CZLP:8%Ce 3+ , Mn 2+ phosphor. The luminous mechanism and ET phenomenon are explained by using the Tanabe-Sugano diagram of Mn 2+ ion and the energy level diagrams of Ce 3+ and Mn 2+ ions. The experimental results are favorable for the improving and adjusting of luminescence properties of other phosphors.