A novel red emitting phosphor LiBaB9 O15 :Sm2+ /Sm3+ , li+ with broad excitation band for white LEDs.

A novel tunable red emitting phosphor LiBaB9 O15 :Sm2+ /Sm3+ , Li+ with broad excitation band was synthesized by a high temperature solid-state method. Luminescence properties were investigated in detail by luminescence, X-ray photoelectron spectroscopy (XPS) spectra and CIE chromaticity coordinates. XPS data confirmed that there were Sm3+ in LiBaB9 O15 :Sm3+ and Sm2+ /Sm3+ in LiBaB9 O15 :Sm2+ /Sm3+ , respectively. Spectral property of LiBaB9 O15 :Sm3+ , LiBaB9 O15 :Sm3+ /Sm2+ and LiBaB9 O15 :Sm2+ , Li+ presented that the excitation band of Sm3+ widened and the excitation band of Sm2+ ranged from 350 to 450 nm. And the red light color is tunable with changing Li+ concentration. The results indicated that LiBaB9 O15 :Sm2+ /Sm3+ , Li+ may be promising red phosphor for white light emitting diodes.