Unraveling the Evolution of Luminescence Center in an Eu-Doped Orthophosphate: Beyond the Probe Limitation to Trace Activator

To precisely tune the performance of phosphors, a proper understanding of the luminescence center is necessary. However, precisely probing into the luminescence center is still challenging. In this study, the luminescence center and the evolution are revealed in Eu3+-doped Li4Zn(PO4)(2) (LZP:Eu) depending on the activator in as low as trace amounts: Eu3+ ions evolve from the LZP lattice to hardly measurable EuPO4 impurities. By utilizing the spectroscopic probe effect of Eu3+ ion with multiscale characterizations, pressure-induced spectral behavior, and ab initio calculations, the luminescence origin, local environment, and nanostructure evolution are fully deciphered. The contribution of the two luminescence centers during the evolution process is deeply elucidated by steady spectra and decay kinetics analysis. This study provides a broader understanding of the luminescence center from micro- to macro-length, which would be beneficial for the design and modulation of luminescent materials.