Abstract
Eu3+-doped BaZrO3 (BaZrO3:Eu3+) phosphor powders were prepared using a solid-state reaction by changing the molar concentration of Eu3+ within the range of 0.5 to 30 mol%. Irrespective of the molar concentration of Eu3+ ions, the crystal structures of all the phosphors were cubic. The excitation spectra of BaZrO3:Eu3+ phosphors consisted of an intense broad band centered at 277 nm in the range of 230~320 nm. The emission spectra were composed of a dominant orange band at 595 nm arising from the 5D0→7F1 magnetic dipole transition of Eu3+ and two weak emission bands centered at 574 and 615 nm, respectively. As the concentration of Eu3+ increased from 0.5 to 10 mol%, the intensities of all the emission bands gradually increased, approached maxima at 10 mol% of Eu3+ ions, and then showed a decreasing tendency with further increase in the Eu3+ ions due to the concentration quenching. The critical distance between neighboring Eu3+ ions for concentration quenching was calculated to be 11.21 Å, indicating that dipole-dipole interaction was the main mechanism of concentration quenching of BaZrO3:Eu3+ phosphors. The results suggest that the orange emission intensity can be modulated by doping the appropriate concentration of Eu3+ ions.