Dual-mode luminescence anti-counterfeiting and white light emission of NaGdF4:Ce,Eu,Tb/carbon dot hydrophilic nanocomposite ink

NaGdF4:Ce,Eu,Tb nanocrystals were successfully prepared by a one-step hydrothermal method with Ce3+ ions as sensitizers, Eu3+ and Tb3+ ions as activators, and polyethylenimine (PEI) as surfactants. Color-adjustable fluorescence emission was achieved by the energy transfer effect between rare earth ions. Blue fluorescent carbon quantum dots (CDs) with a double UV response under 254 nm and 365 nm excitation were synthesized by a one-step hydrothermal method. A hydrophilic NaGdF4:Ce,Eu,Tb/CD composite ink was prepared by an easy physical mixing method. Because of the electrostatic self-assembly effect, the color adjustable luminescence was achieved in a few seconds, and the white light emission with color coordinates of (0.32, 0.32) was obtained. A dual-mode luminescence anti-counterfeiting pattern was designed and achieved by excitation with ultraviolet light at 254 nm and 365 nm.

Automated summary

NaGdF4:Ce,Eu,Tb nanocrystals were prepared through a one-step hydrothermal method using Ce3+ ions as sensitizers, Eu3+ and Tb3+ ions as activators, and polyethylenimine (PEI) as surfactants. Color-adjustable fluorescence emission was achieved through energy transfer between rare earth ions. Blue fluorescent carbon quantum dots (CDs) with dual UV response under 254 nm and 365 nm excitation were synthesized. A hydrophilic NaGdF4:Ce,Eu,Tb/CD composite ink was prepared by physical mixing, allowing for color adjustable luminescence and obtaining white light emission with color coordinates of (0.32, 0.32). A dual-mode luminescence anti-counterfeiting pattern was designed and achieved by UV excitation at 254 nm and 365 nm.