A novel redshift mechanism of Ce3+ emission in ZrO2-Ce: YAG composite phosphor ceramics

In this work, ZrO2-Ce: YAG composite phosphor ceramic for the application of high brightness w-LEDs was fabricated for the first time. A novel redshift mechanism of Ce3+ emission is discovered in the composite ceramics that the oxygen vacancy introduced into YAG lattice by the high-temperature reduction of Zr4+ can cause a remarkable non-radiative transition of excited electrons and produce a large redshift from 540 nm to 570 similar to 610 nm. This kind of redshift has provided a new approach to the supplement of the red component in Ce3+ emission spectra beyond the regular ways of larger rare-earth ions doping or M2+-N4+ double substitution.