Luminescence properties of GdOCl:Eu3+ red-emitting phosphors for white light-emitting diodes.

The structural and photoluminescence properties of Eu3+ activated GdOCl red-emitting phosphors were investigated. All the GdOCl: x Eu3+ (x = 0–0.125) phosphors are crystallized in the tetragonal PbFCl-type structure (P 4 / nmm space group). Under the 289 nm excitation, all the phosphors show bright red emissions which are originated from the 5D 0 → 7F J (0 ≤ J ≤ 4) transitions of Eu3+. The GdOCl:0.075Eu3+ phosphor presents the strongest emission intensity, and concentration quenching phenomenon dominated by the nearest-neighbor ions interaction appears as x exceeds 0.075. The color purity and quantum efficiency (under 289 nm excitation) for GdOCl:0.075Eu3+ phosphor reach 92% and 68.7%, respectively, which are comparable or even better than some of the commercialized red-emitting phosphors. Furthermore, the emission intensity at 423 K reaches ~56.1% of that at 303 K for GdOCl:0.075Eu3+ phosphor, such good thermal stability is due to the relative high activation energy (0.18 eV). The present results indicate that the GdOCl:0.075Eu3+ phosphor is a competitive candidate for white light-emitting diodes applications. [ABSTRACT FROM AUTHOR]