Spectral-converting behaviors of Er3+ and Er3+-Yb3+ doped YOCl phosphors

Luminescent materials composed of Y1−m−nErmYbnOCl (m = 0.001-0.1, n = 0.005-0.1) were prepared via a solid-state reaction using NH4Cl flux. Photoluminescence spectra, the dependence of the luminescent intensity as a function of Er3+ content, and their CIE coordinates of the Er3+-doped layered YOCl compounds were also investigated under near-ultraviolet (NUV) and visible lights. The spectral up-converting properties of Er3+ and Er3+-Yb3+ in YOCl phosphors were elucidated under 980 and 1550 nm diode laser irradiations. This up-conversion emission spectra and the pump power dependence versus emission intensity observed in the Y0.9Er0.1OCl up-conversion phosphors gave rise to one- and two-photon processes. The up-conversion mechanism of Er3+ and Yb3+ ions in YOCl was described by a schematic energy-level diagram. Through the use of these up-conversion luminescent materials, the desired emitting lights throughout the orange and red regions of the spectra were achieved.