Blue excited photoluminescence of Pr doped CaBi_2Ta_2O_9 based ferroelectrics

摘要

Pr~(3+) doped CaBi_2Ta_2O_9 based bismuth layered-structure oxides were synthesized by a simple solid state reaction method. The photoluminescence properties of the samples were investigated by excitation and emission spectra. Photoluminescence excitation spectra show that the samples have broad blue excitation band located at 430-5 lOnm, which covers the emission wavelength of commercial blue light-emitting diode (LED) chips. Upon the excitation of 450 nm light, a novel red emission centered at 621 nm of Prdoped CaBi_2Ta_2O_9 makes it useful in the white LEDs. In addition, it was also found that the photoluminescence can been improved by partial substituting Sr for Ca. These Pr~(3+) doped CaBi_2Ta_2O_9 based ferroelectrics could possibly be used as a multifunctional material for a wide range of applications, such as integrated electro-optical devices.