Structure, energy level analysis and luminescent properties of a novel broadband blue-emitting phosphor KBaYSi2O7: Ce3+.

A novel blue phosphor KBaYSi 2 O 7 : Ce 3+ was synthesized via a simple solid-state reaction. Rietveld refinement results indicate that this compound crystallizes in a space group of monoclinic P121/n1(14) and Ce 3+ ions are occupying the Y 3+ site. The excitation spectra of KBaYSi 2 O 7 : Ce 3+ phosphor show broad absorption band in range of 250–400 nm, and this phosphor exhibits an intense blue emission centered at 440 nm upon excitation at 365 nm. The centroid shift and crystal field splitting of Ce 3+ 5 d energy levels in KBaYSi 2 O 7 : Ce 3+ was investigated in details. The concentration of Ce 3+ is optimized to be 0.02 and the corresponding critical distance is calculated as 25 Å. The as-prepared phosphor shows good thermal stability (75% at 100 °C), and the internal quantum efficiency is 35%. All the results indicated that KBaYSi 2 O 7 : Ce 3+ may have the potential application as blue-emitting phosphors for near-UV pumped white light-emitting diodes. [ABSTRACT FROM AUTHOR]