Fast preparation of Ce3+-activated scandate for high-color- rendering warm white-light illumination by cation exchange

High-color-rendering illumination is an important application direction in the development of white-light-emitting diodes (WLEDs). In this work, the Ce3+-activated Sr3Sc4O9-CaSc2O4 phosphors are successfully obtained by cation exchange from Sr3Sc4O9:Ce3+. Due to the high reaction activity and reaction rate in CaCl2 melt, the exchange process can be realized under much lower temperature than that of traditional high-temperature sintering, even near the melting point of CaCl2 (1058 K). The color tunability of as-prepared phosphors from orange to green is also easily tailored by adjusting the content of CaCl2. What is more, combining the exchanged phosphor and a blue LED, a high-color-rendering warm WLED is also demonstrated (CCT = 3555 K, Ra = 88, R9 = 94), which is comparable to most of commercial WLEDs. The obtained results not only manifest the potential application of ion exchange in preparing luminescent materials and adjusting corresponding spectral properties, but also provide a promising platform in developing the high-color-rendering warm white-light illumination.