Sr–Ba combinational effect on spectral broadening of blue (Sr, Ba)5(PO4)3Cl:Ce3+ phosphor for a high color-rendering index

Abstract Spectral broadening of blue apatite phosphors (Sr, Ba) 5 (PO 4 ) 3 Cl:Ce 3+ was achieved by changing Sr–Ba combinations. The blue colors came from 5 d 1 to 4 f 1 transitions of Ce 3+ ions, and the excitation bands were ranged from 250 nm to 400 nm. The broad Raman spectrum in Sr 2.45 Ba 2.45 (PO 4 ) 3 Cl:Ce 3+ supported its highest disorder, leading to the spectral broadening with a half width of 95.5 nm. The temperature dependence showed the emission maintenance of 80% around 100 °C. The 310 nm-pumped white LED was simulated so as to show a color rendering index ( R a ) of 74 at white point.