LAUSR

Abstract In this work, a series of Ca9(1-m-n)La(PO4)5SiO4F2:mEu, nMn (CLPS:mEu,nMn, 0 ≤ m ≤ 3%, 0 ≤ n ≤ 4%) phosphors were designed for multifunctional applications. The phase purity was evaluated by XRD technique, which revealed that the obtained samples were single-phase. When the Eu was doped, it was found that the emission spectra exhibited different characteristics depending on the excitation wavelength. More than one Eu2+ emission center was confirmed in the Eu-activated CLPS phosphors, and the optimal Eu2+ doping concentration was determined to be 1 mol%. To realize tunable emission, the Eu-Mn codoped CLPS phosphors were synthesized, in which the efficient energy transfer (ET) from Eu2+ to Mn2+ occurred. The corresponding ET mechanism was discussed by using the Dexter's ET formula. Upon 365 nm excitation, the thermal quenching properties of both Eu-single-doped and Eu-Mn-codoped CLPS phosphors were evaluated, and the spectral features were interpreted. Under 300 nm excitation, it was found that the CLPS:1%Eu sample showed different decay rates for the Eu2+ and Eu3+ emission intensities with temperature, which was considered to apply to optical thermometry. High sensitivity was obtained in the present phosphor.