Tunable color emission in LaScO 3 :Bi 3+ ,Tb 3+ ,Eu 3+ phosphor

Abstract LaScO 3 : x Bi 3+ , y Tb 3+ , z Eu 3+ ( x = 0 − 0.04, y = 0 − 0.05, z = 0 − 0.05) phosphors were prepared via high‐temperature solid‐state reaction. Phase identification and crystal structures of the LaScO 3 : x Bi 3+ , y Tb 3+ , z Eu 3+ phosphors were investigated by X‐ray diffraction (XRD). Crystal structure of phosphors was analyzed by Rietveld refinement and transmission electron microscopy (TEM). The luminescent performance of these trichromatic phosphors is investigated by diffuse reflection spectra and photoluminescence. The phenomenon of energy transfer from Bi 3+ and Tb 3+ to Eu 3+ in LaScO 3 : x Bi 3+ , y Tb 3+ , z Eu 3+ phosphors was investigated. By changing the ratio of x , y , and z , trichromatic can be obtained in the LaScO 3 host, including red, green, and blue emission with peak centered at 613, 544, and 428 nm, respectively. Therefore, two kinds of white light‐emitting phosphors were obtained, LaScO 3 :0.02Bi 3+ ,0.05Tb 3+ , z Eu 3+ and LaScO 3 :0.02Bi 3+ ,0.03Eu 3+ , y Tb 3+ . The energy transfer was characterized by decay times of the LaScO 3 : x Bi 3+ , y Tb 3+ , z Eu 3+ phosphors. Moreover absolute internal QY and CIE chromatic coordinates are shown. The potential optical thermometry application of LaScO 3 :Bi 3+ ,Eu 3+ was based on the temperature sensitivity of the fluorescence intensity ratio (FIR). The maximum S a and S r are 0.118 K −1 (at 473.15 K) and 0.795% K −1 (at 448.15 K), respectively. Hence, the LaScO 3 :Bi 3+ ,Eu 3+ phosphor is a good material for optical temperature sensing.