Near-infrared Emission of Redispersible Er³⁺, Nd³⁺, and Ho³⁺ Doped LaF₃ Nanoparticles

Abstract

Nanoparticles of LaF 3 doped with Ln 3+ (Ln ) Eu, Er, Nd, and Ho) have been prepared that are dispersible in organic solvents. From the spectrum of Eu 3+ it has been concluded that the dopant ion occupies a La 3+ site. The luminescence decays are fitted biexponentially. A given possible explanation for this is a different probability of nonradiative decay for ions at or near the surface and ions in the core of the particles. The lifetimes of Eu 3+ luminescence at a doping concentration of 5% were 7.7 ± 0.2 and 2.9 ± 0.2 ms, indicative of very high quantum yields. The particles doped with Er 3+ , Nd 3+ , and Ho 3+ are promising materials for polymer-based optical components, because they show luminescence in the telecommunication window (i.e., Er 3+ at 1530 nm, Nd 3+ at 1330 nm, and Ho 3+ at 1450 nm).

Luminescent and hydrophilic LaF3–polymer nanocomposite for DNA detection

“…Therefore, it is still challenging chemists to find more efficient probes. Among these luminescent biomaterials, luminescent lanthanide ion-doped nanocrystals have become attractive due to their unique luminescence properties, such as high quantum yields, low photobleaching, narrow emission bands and especially longer luminiscent lifetimes (μs-ms range), allowing for gated time-resolved fluorescence (15)(16)(17)(18)(19)(20)(21)(22)(23). Hence, lanthanide ion-doped nanocrystals are promising as alternative materials for biolabels.…”

Radiative Lifetime Modification of LaF3:Nd Nanoparticles Embedded in 3D Silicon Photonic Crystals

“…[ 42 ] The synthesis was carried out at 90 ° C rather than 75 ° C to increase the particle size. After formation of the LaF 3 :Nd nanoparticles, an extra 7 nm of LaF 3 was grown on the shell to increase the luminescence yield.…”

Controlled synthesis of Eu3+-doped La2O2S nanophosphors by refluxing method

“…7 F 2 transition (624 nm) of Eu 3þ -doped La 2 O 2 S nanocrystals. The decay part of the curve can only be fitted by two-exponential function with a long decay time 1 (1.2 ms) and a short decay time 2 (0.4 ms), which is similar to that of Eu 3þ in LaF 3 nanoparticles [10]. In nanosized phosphors, 1 is the lifetime of conventional emission and 2 is the lifetime of the same level of rare earth ions near and/or on the surface.…”

“…Among many phosphors based on rare earth compound host materials, much work has been focused on rare-earth-doped oxide, phosphate, orthovanadate, borate and fluoride [6][7][8][9][10]. As efficient phosphors, however, rare-earth-doped oxysulphide nanocrystals were given rather little attention.…”