Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7840270 | Journal of Luminescence | 2018 | 9 Pages |
Abstract
Optical properties of Ce3+:5dâ4f luminescence in garnet compounds are strongly related to the energy locations of the excited 5d levels and the host conduction band (CB). By constructing the vacuum referred binding energy (VRBE) diagram including information on these energy location for GdyY3-yAl5-xGaxO12 garnet (GYAGG) from the measured spectroscopic data, the luminescence quenching and persistent luminescence properties of GYAGG:Ce3+(-Cr3+) were discussed. The quantum yield (QY) of Ce3+:5dâ4f in GYAGG:Ce3+ is clearly related to the energy gap, ÎE5d1âCB, between the lowest 5d level and the bottom of conduction band in the constructed VRBE diagram. This result indicates that the luminescence quenching of GYAGG:Ce3+ is caused by the thermal ionization. For GYAGG:Ce3+-Cr3+ persistent phosphors, the depth of the electron trap formed by Cr3+ was remarkably changed from 0.27 to 0.69â¯eV by varying the Gd and Ga contents. The estimated VRBE value of Cr2+ in GYAGG can be used as effective value to predict the electron trap depth by Cr3+ in other oxide compounds as well as garnet hosts.
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
Kazuki Asami, Jumpei Ueda, Mamoru Kitaura, Setsuhisa Tanabe,