Fluorescence properties of LaOF: Er, Eu phosphors and their application in fluorescence anti-counterfeiting

Rare-earth-doped luminescent materials have great application prospects in anti-counterfeit identification. First, LaOF:Er, Eu phosphors with multi-mode luminescence were prepared by a heat treatment precursor using a hydrothermal method . Experimental results show that the emission intensity in green and orange-red light regions can be adjusted by regulating the raw material concentration of Eu 3+ . Upon excitation at 380 and 395 nm, a series of samples was observed to be green and orange-red, respectively, which indicates multi-mode luminescence characteristics. Study on variation of the environment around Eu 3+ ions based on the unique “probe” characteristics of Eu 3+ . Moreover, the prepared powder was applied to develop latent fingerprints on different substrates, which resulted in clearly defined friction ridge details of fingerprints under 395 nm ultraviolet light. Finally, according to these luminescent features, we chose the appropriate phosphors to make a series of luminescent patterns. The typical examples demonstrate that the multi-mode luminescent characteristic of the patterns can be used in anti-counterfeiting.