Broad yellow orange emission from SrAl2O4:Pr3+ phosphor with blue excitation for application to white LEDs

Photoluminescence excitation to intermediate atomic levels of rare earth activator ion (praseodymium) situated intragap in alkaline earth aluminate (AEA) SrAl2O4 has been tailored. This lead to blue excitation (2.7 eV) of large band gap AEA possible. Photoluminescence (PL) emission in the visible region extends from 525 to 650 nm corresponding to transition from 3P0 and 1D2 excited states to different 3HJ and 3FJ states of Pr3+, broadened by crystal field effect of SrAl2O4. Thus SrAl2O4:Pr3+ promise to be a good candidate for solid state lighting in conjunction with blue LED.