Synthesis and optical applications of Yb3+/Er3+ co-doped Ba0.6Bi0.4F2.4 and its heterostructured Ca0.6Bi0.4F2.4 upconversion luminescent materials

Bismuth-based composite fluoride upconversion luminescent materials exhibit uniform size and excellent upconversion properties. These materials have potential applications in photodynamic therapy, anti-counterfeiting technology, and bio-imaging. Thus, bismuth-based composite fluoride luminescent materials have been the subject of extensive study in recent years. This paper focuses on the design and synthesis of bismuth-based composite fluorides, specifically Yb 3+ /Er 3+ co-doped Ba 0.6 Bi 0.4 F 2.4 and its heterostructured Ca 0.6 Bi 0.4 F 2.4 upconversion luminescent materials. The study involves measuring room temperature fluorescence spectra, fluorescence lifetime, and quantum yield, demonstrating the exceptional luminescence performance of Ca 0.6 Bi 0.4 F 2.4 :Yb 3+ /Er 3+ . More importantly, we successfully obtained transparent lanthanide-doped Ca 0.6 Bi 0.4 F 2.4 thermoplastic polyurethane (TPU) luminescent films and upconversion luminescent inks. This work highlights the great potential of upconversion nanomaterials in anti-counterfeiting fields.