Enhancement of blue-green photoluminescence in B2O3 fritted ZrO2:Ce3+ phosphor

Blue-green emission of ZrO2:Ce3+ phosphor, prepared by solid-state reaction, is demonstrated. The phosphor presents a strong and broad photoluminescence band centered at 496 nm with excitation at 291 nm. The optimized Ce content is 2.5 mol% for the strongest emission of ZrO2:Ce3+ phosphors prepared without B2O3. The PL intensity is enhanced by at least 3 dB by adding 5.0 mol% B2O3 within the ZrO2:Ce3+ containing 5.0 mol% Ce during synthesis. Increase of the B2O3 flux effectively induces the Ce ions to substitute the Zr ions in ZrO2 lattice and causes the ZrO2 lattice distortion. The formation of Ce0.75Zr0.25O2 compound within the ZrO2:Ce3+ occurred when the Ce content is greater than or equal to 2.5 mol% for the phosphors prepared without B2O3 and leads to a degradation of the phosphor PL intensity due to the host effect. The addition of B2O3 during the preparation of phosphors containing Ce ions lower than or equal to 5.0 mol% essentially restrains the Ce0.75Zr0.25O2 formation and then enhances the blue-green PL.