Adjustable luminescence properties of Eu3+ and Bi3+ codoped Ca3Zn3Te2O12 phosphor

Ca3Zn3Te2O12:Bi3+, Ca3Zn3Te2O12:Eu3+, Ca3Zn3Te2O12:Eu3+/Bi3+ are prepared successfully in air. The crystal phase, microscopic image, and optical properties of samples are investigated by the X-ray difractometer, scanning electron microscopy, and edinburgh steady-state FLS 980 spectrograph. The green emission of Ca3Zn3Te2O12:Bi3+ phosphor with excitation at 314 nm is observed and its broad emission spectrum in the range of 360 -790 nm is attributed to the P-3(1) -> S-1(0) transition of Bi3+ ion. Under excitation at 395 nm, the red emission of Ca3Zn3Te2O12:Eu3+ is found, the chromaticity coordinates are (0.6392, 0.3605), and its PL spectrum is in the rang of 575 -750 nm because of the D-5(0) -> F-7(0), F-7(1), F-7(2), F-7(3), and F-7(4) transations of Eu3+ ion. The doping Bi3+ ion can affect the luminescence properties of Ca3Zn3Te2O12:Eu3+ phosphor. The adjustable color light from green to yellow of Ca3Zn3Te2O12:Eu3+, Bi3+ phosphor with excitation at 314 nm is revealed when Eu3+ concentration is changed from 0 to 12 mol%. When the excitation wavelength is 395 nm, Ca3Zn3Te2O12:Eu3+, Bi3+ phosphor only emits red light with emission spectrum in the rang of 575 -750 nm. The energy level diagrams of Eu3+ and Bi3+ in Ca3Zn3Te2O12:Eu3+, Bi3+ are drawn, which is used to analyze the luminous mechanism of samples.