Defect-assisted dynamic multicolor modulation in KLu₃F₁₀:Tb crystals for anti-counterfeiting

Abstract

Excitation-dependent dynamic multicolor luminescent materials show promising applications in the field of anti-counterfeiting. However, for most ultraviolet (UV) excited lanthanide doped materials, more than two types of activators are incorporated...

Excitation-Controlled Host–Guest Multicolor Luminescence in Lanthanide-Doped Calcium Zirconate for Information Encryption

“…However, this has not attracted much attention to date, and there are very few examples: Cs 3 TbCl 6 nanocrystals produce blue luminescence of the host under 365 nm excitation, while the green luminescence of Tb 3+ is produced under 254 nm excitation, enabling colorful luminescence from green to blue under 260-360 nm excitations [24]. KLu 3 F 10 :Tb crystals emit blue light from defects in KLu 3 F 10 under 365 nm excitation and green light from Tb 3+ under 254 nm excitation, with the luminescence tuning from green to blue under 250-370 nm excitations [25]. Combining the self-trapped exciton luminescence of the matrix and the luminescence of doped lanthanide ions, Cs 2 Ag 0.3 Na 0.7 InCl 6 :Yb 3+ /Eu 3+ /Ho 3+ microcrystals display yellow, red, and green light under 300, 394, and 980 nm excitations, respectively [26], and a similar phenomenon has been found in ZrO 2 :Gd 3+ nanoparticles [27].…”

Dual-signalled magneto-optical barcodes with lanthanide-based molecular cluster-aggregates

“…4,5 Considering these issues, researchers have introduced lanthanide-based luminescent materials with one or more emitter centres, creating intricate optical barcodes. [6][7][8][9][10][11][12][13] The intrinsic narrow emission bands characteristic of each lanthanide ion and the presence of a unique spectral fingerprint, depending on the crystal-field surrounding the lanthanide ion, 14,15 make them an attractive choice when aiming for more secure optical barcodes. For these luminescent barcodes, the read-out can be realized by the naked eye or by using an emission detector.…”