Long-lived Photon Upconversion Phosphorescence in RbCaF(3):Mn(2+),Yb(3+) and the Dynamic Color Separation Effect

The development of luminescence materials with long-lived upconversion (UC) phosphorescence and long luminescence rise edge (LRE) is a great challenge to advance the technology of photonics and materials sciences. The lanthanide ions-doped UC materials normally possess limited UC lifetime and short LRE, restricting direct afterglow viewing in visual images by the naked eye. Here, we show that the RbCaF(3):Mn(2+),Yb(3+) UC luminescence material generates a long UC lifetime of ∼62 ms peaking at 565 nm and an ultralong LRE of ∼5.2 ms. Density functional theory calculations provide a theoretical understanding of the Mn(2+)-Yb(3+) aggregation in the high-symmetry RbCaF(3) host lattice that enables the formation of the long-lived UC emission center, superexchange coupled Yb(3+)-Mn(2+) pair. Through screen printing ink containing RbCaF(3):Mn(2+),Yb(3+), the visualized multiple anti-counterfeiting application and information encryption prototype with high-throughput rate of authentication and decryption are demonstrated by the dynamic color separation effect.