Properties Of Lanthanide Ions Research Articles

A Review of the Physical, Optical and Photoluminescence Properties of Rare Earth Ions Doped Glasses

Doping glasses with rare-earth ions have garnered significant attention among researchers worldwide. This interest stems from the widespread utilization of rare-earth ions to enhance the optical characteristics of host glasses and exploit the unique spectroscopic properties arising from their optical transitions in the intra-4f shell. Thus, this study reviewed the exceptional potential of rare-earth ion-doped glasses (REIs) in various applications such as solid-state lasers, photonic devices, communication optical fibers, and white light emission. Various methods for the fabrication of glass such as direct melt quenching, sol-gel, ion exchange, sputtering and co-doping techniques were reviewed extensively. The Specific focus was on the physical, optical and photoluminescence properties of glasses produced from glass formers co-doped with rare earth ions. The investigation centers on the comprehensive current applicability of REI-doped glasses. The review concludes based on the physical, optical and photoluminescence properties of rare earth ion-doped glasses that they are extremely useful in photonics, lasers, biomedical and optical communication applications.

Antibacterial mechanism and enhancement of antibacterial activity under visible light in Er3+-doped BiOBr

The introduction of oxygen defects in semiconductor electronic structures is considered to be an effective strategy to improve their photocatalytic activity. In this work, rare-earth Er3+−doped BiOBr (Er/BiOBr) with oxygen-rich vacancies (OVs) was prepared via simple hydrothermal method. Compared with pure BiOBr, Er/BiOBr has a narrower band gap and more abundant OVs, which together improve the separation efficiency of photogenerated carriers. The introduction of Er not only creates impurity states between conduction band (CB) and valence band (VB), but also produces more OVs as electron traps. Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) were used as evaluation systems for these materials with different Er3+ doping contents. The results showed that under the combined action of ·O2− and H2O2, 2.0% EBB samples with Er3+ doping content of BiOBr showed the best broad-spectrum antibacterial activity, and E. coli and S. aureus were completely inactivated at 0.03 mg ml−1 and 0.05 mg ml−1 concentrations. The surface and interfacial structures of Er/BiOBr samples were studied by XRD, brunauer-emmet-teller method, SEM, TEM and EDX. OVs and photogenerated carrier separation in Er/BiOBr were determined by ESR, PL and photochemical detection methods. More importantly, through the detection of lipid peroxidation and bacterial respiratory chain dehydrogenase activities, the internal and external processes of ROS on bacterial inactivation were determined, and the photocatalytic antibacterial mechanism was summarized. This study for the antimicrobial properties of rare earth ions doped improve photocatalytic materials provides a new train of thought.

Lanthanide-based nanothermometers for bioapplications: excitation and temperature sensing in optical transparency windows

Review article summarizing the current state of knowledge on remote optical nanothermometers based on the properties of lanthanide ions, both excitable and emitting within the biological windows range.

Structural, luminescent, and electronic properties of ASnO3 (A = Ca, Sr, and Ba) with doping of Eu, Dy, and Er ions

This study investigated the structural and luminescent properties of rare earth (RE) ion (RE = Eu3+, Dy3+, and Er3+)-doped ASnO3 (ASnO3:RE), where A = Ca, Sr, and Ba. X-ray diffraction and Rietveld refinement analyses revealed that the lattice structures for A = Ca, Sr, and Ba were orthorhombic, pseudo-cubic, and cubic, respectively. As for the luminescent properties, the emission characteristic of each RE ion was clearly identified in our samples. Interestingly, it was commonly observed for all three RE ions that the emission intensities of the three RE ions were strongest and weakest in CaSnO3:RE and BaSnO3:RE, respectively. These results suggest the close relations of the luminescence properties of RE ions with the structural symmetry of the host material, ASnO3. In addition, the electronic structure and lattice dynamics of ASnO3:RE were investigated through theoretical calculations and optical measurements. The findings of this study provide important insights into the properties of RE ion-doped ASnO3 materials and their potential applications in optoelectronic devices.

Structural, elastic and optical properties of rare earth ions (Nd3+, Dy3+, & Nd3+/Dy3+) incorporated B2O3+K2O+ZnO+ZnF2 glasses

Herein we report the effect of rare earth ion; REI (Nd3+, Dy3+, & Nd3+/Dy3+) on the structural, optical, luminescence and elastic characteristics of B2O3+K2O+ZnO+ZnF2 glasses produced via the melt-quenching process. The structural, optical, luminescence and elastic features of the produced glass samples were comprehensively characterised using XRD, FTIR, UV–Visible, Luminescence, and decay analysis methods. The XRD study shows that even after doping or co-doping with REIs, the glass samples exhibit amorphous characteristics. It was observed that physical parameter analysis revealed the occurrence of non-bridging oxygens, while FTIR analysis revealed the predominance of borate groups for all the prepared samples. Only transition peaks discovered in the BNd, BNdDy and BDy samples were affected, according to a UV–visible absorption spectra examination, while the rest were left unchanged. Ionic and covalency nature with the host were identified, respectively, followed by the Judd-Ofelt analysis for BNd and BDy glasses. Peak emission and lifetime data were analysed for samples of BNd, BDy, and BNdDy. The CIE diagram shows that the BDy emits warm white light with an efficiency of 81%. Using the Makishima - Mackenzie model, the structural compactness (elastic properties) of the manufactured sample was thoroughly addressed.

Luminescence characteristics of Dy3+ doped sodium alumina borate glass: Role of silver

Metallic nanoparticle (NP) doped glasses have been studied as promising candidates for various technological applications due to their ability to improve the luminescence properties of rare earth ions. In this work, Dy2O3 and Ag2O co-doped sodium alumina borate glasses were synthesized by conventional melt-quenching technique. Raman analysis verified the existence of [BO3] and [BO4] groups with B–O stretching vibrations in the prepared glasses. Transmission electron microscope images confirmed the presence of spherical Ag NPs, whose average diameter is about 7.60 nm, in H-0.5Dy1Ag glass matrix. The optical and luminescence properties were investigated according to Ag concentrations. The negative value of the bonding parameters, calculated from the absorption spectra, indicates the ionic nature between the Dy3+ ions and its surrounding ligands. In order to determine the nature of the Dy-O bond and the symmetry around the Dy3+ ion environment, Judd–Ofelt intensity parameters (Ω λ, λ = 2, 4, 6) were obtained from the absorption spectra. The luminescence spectra obtained under 350 nm excitation exhibits four emission bands at 481 (4F9/2→6H15/2), 572 (4F9/2→6H13/2), 662 (4F9/2→6H11/2), and 750 (4F9/2→6H9/2) nm. The intensity of emission spectra increases with Ag2O content until 1.0 wt% in H-0.5Dy-yAg glasses and then decreases due to the back-energy transfer (ET) from Dy3+ to Ag+. The ET mechanism from Ag+ to Dy3+ ion for H-1Ag-xDy glasses were investigated through Forster-Dexter’s theory and were found to be quadrupole-quadrupole type. The various radiative properties were calculated by using Judd-Ofelt intensity parameters and emission spectra. It was found that the 572 nm emission band, located in the yellow region, has higher radiative parameters. As a function of Ag concentration, the Y/B values, Commission Internationale d’Eclairage (CIE) chromaticity coordinates (x,y) and correlated color temperatures (CCT) were evaluated. The CIE chromaticity coordinates and CCT values of all glasses are located in the white light region. The decay time values of 1S0→3D1 transition of Ag+ ions and 4F9/2→6H13/2 transition of Dy3+ ions confirm the ET from Ag+ to Dy3+ ions. Overall, the present study indicates that the synthesized glasses with Ag addition exhibits improved luminescence, making them potential candidate for white LEDs.

Low-temperature in situ preparation of Eu3+/Tb3+-doped CaMoO4/SrMoO4 nanoparticle thin films and their application in anti-counterfeiting.

Rare earth-doped metal oxide thin films exhibit remarkable potential for application in anti-counterfeiting, owing to their exceptional fluorescent properties. However, the existing fabrication techniques for these rare earth-doped luminescent thin films are predominantly complex and necessitate high-temperature conditions. In light of this issue, we present a low-temperature method for in situ fabrication of luminescent Ca1-xMoO4:Eux3+ and Sr1-xMoO4:Tbx3+ nanocrystal thin films by a solution deposition process. The developed method has the advantages of simple operation, rapid and low-temperature synthesis. The optimal chemical compositions of molybdate-based luminescent films are Ca0.90MoO4:Eu0.103+ and Sr0.90MoO4:Tb0.103+. Moreover, we evaluate the practical feasibility of luminescent nanoparticle films in the field of anti-counterfeiting by combining the unique fluorescent properties of rare earth ions and designing customized fluorescent patterns.

Spectral Analysis and Gain Modeling and Numerical Simulation of Bismuth-doped Fiber Amplifier

Fiber optic amplifier is an important component of fiber optic communication and the use of the properties of rare earth ions to dope the fiber core is an important way to obtain greater amplification and reduce loss. Because of the unique light-emitting properties of Bismuth ions, the Bismuth doped fiber amplifier (PDFA) has a wide range of applications in the field of fiber amplifier. This paper focuses on the spectral analysis of Bismuth-doped ( ) fiber amplifiers under different parameters by referring to the absorption spectrum of . And the energy level structure of was selected for a wide range of amplification windows → pumping scheme corresponding to the pumping wavelength of 950 nm, and the rate propagation equation and power transmission equation were established based on the previous work. The numerical simulations were also carried out by MATLAB programming. The effects of doping concentration, fiber length, and pump power on gain, noise index, and output power were analyzed and summarized by MATLAB plotting. In the future, researchers can use neural network algorithms to obtain the combination of Bismuth-doped fiber amplifier parameters that will achieve maximum gain, thus enabling advances in information transmission rates and distances in real-world communications.

A density functional theory (DFT) on the leaching process of weathered crust elution-deposited rare earth ore with lixiviants

The properties of the solution are closely related to their structures. For efficient exploitation of the weathered crust elution-deposited rare earth ores, the properties of RE ions of the solution have been studied in the leaching process of weathered crust elution-deposited rare earth ores. The structures of 10 hydrated RE clusters were optimized at the PBE0/6-311+G(d, p) level by density functional theory (DFT). The electrostatic potential distribution, the interaction, and the binding energy of hydrated RE clusters with different anions were analyzed. The effect of the anion of the lixiviant in the leaching process was studied at the molecular level. The results show that thermodynamics dominates the static leaching of rare earth (RE) in the leaching process. In the leaching of REs from weathered crust elution-deposited rare earth ore, the stability of the hydrated clusters can affect the leaching rate. The anions that form more stable hydrated clusters with RE ions are more conducive to rare earth leaching. The interaction between inorganic anion and water can also reduce the energy of the whole cluster and make the structure more stable. Besides, the binding energy of the clusters indicates that hydrated clusters with heavy REs have lower binding energy than those with light REs. So the heavy REs are more likely to migrate with the solution. This conclusion also fits with the fractionation effect of rare earth partition.

Electric field control of photoluminescence response in lanthanide doped ferroelectric materials: A brief review

Tuning the photoluminescence (PL) properties of lanthanide ions not only provides a deeper understanding of the luminescence mechanism, but also promotes its potential applications in lighting industry, volumetric 3 D display, biological assaying, and medical imaging. The traditional chemical strategies, such as changing the types or concentration of doped ions, changing the composition of host materials, changing the preparation process, etc, can easily adjust the photo excitation, energy transfer and emission processes, which have been widely employed. In spite of the strong ability to tune luminescence intensity and wavelength, these chemical methods are irreversible, which is difficult to observe the dynamic luminescence process and unfavorable for real applications. Recently, enabling in-situ, real-time and reversibly control PL response by the application of electric field has been realized through doping lanthanide ions into ferroelectric host materials. Herein, the electric field control of PL response in lanthanide doped ferroelectric bulks and thin films is summarized. The intrinsic luminescence mechanism under electric field and possible application directions in the future are discussed.

Limits to the sensitivity of a rare-earth-enabled cryogenic vibration sensor

Cryogenics is a pivotal aspect in the development of quantum technologies. Closed-cycle devices have recently emerged as an environmentally friendly and low-maintenance alternative to liquid helium cryostats. Yet the larger level of vibrations in dry cryocoolers forbids their use in most sensitive applications. In a recent work, we have proposed an inertial, broadband, contactless sensor based on the piezospectroscopic effect, i.e., the natural sensitivity of optical lines to strain exhibited by impurities in solids. This sensor builds on the exceptional spectroscopic properties of rare earth ions and operates below 4 K, where spectral hole burning considerably enhances the sensitivity. In this paper, we investigate the fundamental and technical limitations of this vibration sensor by comparing a rigid sample attachment to the cold stage of a pulse-tube cryocooler and a custom-designed exchange gas chamber for acoustic isolation.

Influence of lattice strain on Er3+ ions activated magnesium zirconium phosphate phosphors: Morphological, structural, and photoluminescence properties

Rare earth ions doped alkaline metal zirconium phosphors have recently received significant attention in several applications including light-emitting diodes (LEDs) based solid-state lighting, solar panels, barcode readers and fluorescent labels focusing on the ultraviolet (UV) to visible (Vis) spectrum photoluminescence (PL) properties. Near-infrared (NIR) PL properties of rare earth ions doped magnesium zirconium phosphate (MZP) nanophosphors characteristics have not been investigated and considered as good candidates for optical amplifier and photonics applications. In this study, erbium doped magnesium zirconium phosphate (Er3+doped MgZr4(PO4)6) nanophosphors containing 0.0, 0.25, 0.5, 0.75 and 1.0 mol% Er3+ were synthesised using a sol–gel technique. The samples prepared were calcined at 900 °C. Nanopowders of the samples were examined by the transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy to determine the surface morphology, particle size, crystallographic phase, crystalline structure, and lattice strain. Increasing in the Er3+-ion concentrations do not have significant influence on the crystallite size, with an average crystallite size range from ∼ 28 nm to 32 nm. However, the lattice strain parameter of the Er3+ doped MZP samples decreased slightly as compared to the pure undoped MgZr4(PO4)6. The Er3+dopant was found to influence the photoluminescence properties measured at room temperature under a 980 nm excitation source. Systematic analysis revealed the presence of broad emission band corresponding to the 4I13/2→4I15/2transition. The results showed that 0.5 mol% Er3+doped sample exhibits a full width half maximum (FWHM) value of 38 nm with a long photoluminescence lifetime of 5.47 ms. The results obtained clearly demonstrates that 0.5 mol% Er3+ doped MgZr4(PO4)6 nanophosphors has a huge potential for integrated photonic applications such as lighting, biosensing, compact waveguide amplifiers, and lasers with emission properties in the IR region.

Electrical conductivity and dielectric properties of rare earth ions (Ce3+, Pr3+ and Eu3+) doped in zinc sodium phosphate glass

The zinc phosphate glass (composition Na2–3xMxZnP2O7) doped with different rare earth ions (x = 1 mol% where M = Ce, Pr and Eu), were synthesized by the classical melting and quenching processes. Electrical and dielectric properties including dielectric constantε′(ω), loss tangenttanδ, as well as electric conductivityσac, have been investigated over a wide continuous frequency range from 10−2 Hz to 106 Hz over a temperature range 283 K to 473 K using complex impedance spectroscopy (CIS). The results revealed that the conductivity decreases and activation energy increases with the ionic radii of cations (from Eu3+to Ce3+) likely due to the size mismatch. This behaviour could be attributed to the depolymerization of the glass network by Eu3+. This induces the decrease of the electrostatic binding and strains energies facilitating the passage of sodium ions. The average value of the power law exponent s is interpreted by the correlated barrier hopping (CBH) model.

A new family of Ln-BTC-AC-FM framework intelligent materials: Precise synthesis, structure and characterization for fluorescence detecting of UO22+ and adsorbing dyes

The unique fluorescence properties of rare earth ions and subtle interactions with organic ligands make the target lanthanide metal-organic frameworks show potential development prospects in many fields. Based on this situation, a series of new lanthanide metal-organic frameworks Ln-BTC-AC-FM: (CH3)2NH2[Ln2(BTC)(AC)3(FM)], (Ln=Pr (1), Ce (2), Nd (3), Eu (4), Sm (5), Gd (6), Tb (7), Ho (8), Er (9) and Yb (10), H3BTC=1,3,5-benzenetricarboxylic acid) were synthesized through the reaction of triangular polycarboxylic acid ligand (H3BTC) and rare earth nitrate Ln(NO3)3·6H2O with mixed formic acid (FM) and glacial acetic acid (AC) system. Due to this new type of Ln-BTC-AC-FM MOFs have unique and excellent fluorescence properties, we selected (CH3)2NH2[Eu2(BTC)(AC)3(FM)] (4) to explore its detection performance for UO22+ in aqueous solution. The study found that 4 is a high-efficiency fluorescent probe, which has a good quenching effect on uranium solution, and the quenching rate can reach 98.01%. At the same time, 4 has a good fluorescent response to UO22+, with a higher KSV value of 8.56 × 103 M−1 and a lower detection limit of 4.12 μM. In addition, we also studied the adsorption properties of this series of Ln-BTC-AC-FM MOFs for dyes because of their novel three-dimensional microporous structures. The results showed that 4 has a good adsorption effect on Coomassie Brilliant Blue (CBB) and Eosin. Moreover, it was found that the dye adsorption process was proved to be a suitable pseudo-second-order kinetic model.

Understanding the cyan-emitting phosphor RbNa(Li3SiO4)2: Eu2+ by providing Rb ion vacancies

Abstract In rare earth ions doped luminescent materials, the luminescence properties of rare earth ions occupying different sites are often different. Phosphors Rb1-xNa(Li3SiO4)2: xEu2+ with bimodal cyan emission (472 nm and 523 nm) were synthesized by providing Rb ion vacancies. As a comparison, green phosphors RbNa1-y(Li3SiO4)2: yEu2+ were synthesized by providing Na ion vacancies. Based on the experiment and the formula proposed by Van Uitert, it is found that the emission peak of Eu2+ occupying Na+ sites is 523 nm, while the emission peak of 472 nm is caused by Eu2+ occupying Rb+ sites. Furthermore, according to the Density Functional Theory (DFT) calculation, the formation energy of Eu2+ substituted Na+ sites ( Δ E f = − 4 . 64 eV ) is lower than the formation energy of Eu2+ substituted Rb+ sites ( Δ E f = − 3 . 94 eV ), indicating that Eu2+ doped in RbNa(Li3SiO4)2 is easier to enter Na+ sites. This conclusion is consistent with the spectral information obtained in the experiment. By combining bimodal cyan emitting phosphor Rb0.9Na(Li3SiO4)2: 0.1Eu2+ with red phosphor CaAlSiN3: Eu2+ and a 430 nm LED chip, prepared wLEDs exhibit a high color rendering index (CRI, Ra = 88.9) and a suitable correlation color temperature (CCT) (CCT = 3714 K). The research results indicate that the bimodal cyan emitting phosphor Rb0.9Na(Li3SiO4)2: 0.1Eu2+ obtained through vacancy engineering has important application potential in the field of wLEDs illumination.

Degradable Calcium Phosphate-Coated Upconversion Nanoparticles for Highly Efficient Chemo-Photodynamic Therapy.

The development of a stimulus-responsive nanosystem provides an effective method for improving the accuracy and efficiency of chemotherapy. Meanwhile, traditional photodynamic therapy (PDT) has been substantially restricted by the low dosage of photosensitizer and limited penetration depth of the ultraviolet (UV) or visible light used for excitation. Here, we designed a smart multifunctional nanoplatform by coating core-shell composite mesoporous silica-encapsulated upconversion nanoparticles and chlorin e6 (Ce6) with degradable calcium phosphate, followed by the loading of doxorubicin (DOX). In our structure, the as-synthesized nanoplatform exhibits high responsiveness to a low pH value and degrades rapidly in the weakly acidic tumor microenvironment, allowing the quick release of loaded DOX in tumor sites. Interestingly, the loaded DOX, whose release depends on the pH value and positively correlates with the calcium-ion concentration, enables drug release to be monitored in real time. Combined with photosensitizer Ce6-induced PDT triggered by an 808 nm near-infrared light, synergistic chemo-photodynamic therapy is achieved, thus leading to a highly efficient anticancer treatment in vitro and in vivo. Importantly, the inherent properties of rare earth ions (Gd3+, Yb3+, and Nd3+) make the nanoplatform possess UCL, MRI, and CT trimode imaging capabilities, thus achieving a multiple imaging modality-guided synergistic therapy.

Optical traits of neodymium-doped new types of borate glasses: Judd-Ofelt analysis

Improvement in the optical properties of rare earth ions activated inorganic glasses is one of the challenges in materials science. Driven by this idea a new series of borate glass activated with varying concentrations of neodymium ions (Nd3+) were prepared using the melt-quenching technique. Such glasses were characterized by various analytical tools to determine the Nd3+ contents dependent spectroscopic attributes. Furthermore, Judd-Ofelt intensity parameters of Nd3+ were evaluated. XRD pattern of as-quenched samples confirmed their amorphous nature. FTIR spectra of glasses revealed the bonds stretching and vibration of different borate functional groups. UV–vis spectra of glasses displayed twelve absorption bands accompanied by hypersensitive transition positioned at 581 nm which were used to calculate the oscillator strengths. Judd-Ofelt parameters for all glasses disclosed a similar trend of Ω4 > Ω6 > Ω2. Proposed glass hosts were found to be effective for the enhancement of spectroscopic quality factor of Nd3+ as much as 1.2603, suggesting their usefulness in photonics devices.

Promoting luminescence of Yb/Er codoped ferroelectric composite by polarization engineering for optoelectronic applications

Abstract Ferroelectric oxide nanocrystals, in combination with the robust coupling of an electric field with crystal structure symmetry, makes such systems agreeable to field-induced crystal structural transformation. The luminescent properties of rare earth ions are sensitive to the symmetry of the surrounding crystal field. The luminescence tuning of rare earth ions is an important assignment in the research of luminescent materials. However, the current conditional feasibility and reversibility in the exploration of luminescence modification remain major challenges. In this article, the luminescence modulation of rare earth ions has been developed in Yb3+/Er3+ codoped ferroelectrics glass ceramics containing Bi4Ti3O12 nanocrystals through an electric field. The inclusion of nanocrystals in the glass matrix greatly enhances the electrical resistance. Both upconversion and near-infrared emissions of rare earth ions are effectively enhanced more than twice via polarization engineering. The electric field regulates the photonic properties of rare earth ions with excellent reversibility and nonvolatility in ferroelectrics. The effective modification by electric field provides a new scheme for optical storage and optoelectronic devices.

Effect of chloride on spectrum properties of Pr3+/Ho3+ co-doped fluorozirconate glasses

An effective method of improving the luminescent properties of rare earth ions in fluoride glasses were reported. The Pr3+/Ho3+ co-doped fluorochlorozirconate luminescent glasses were prepared, and the effects of chloride on the spectral properties and structure of the glasses were studied. According to the results, the glass stability is improved, and the luminescence intensity in the visible range is significantly enhanced with the introduction of chloride. By introducing 7.5 mol% BaCl2, the luminescence intensity reaches the maximum and increases by three times. The mechanism of luminescence enhancement is explained by analyzing the correlation between the composition and the structure. The chloride ions disperse outside the glass network before the introduction of 7.5 mol% BaCl2 and increased dispersity of Pr3+ and Ho3+ ions in the fluorozirconate glasses.

Effect of DGA substituent structure on rare earth extraction in nitric acid media

N substitutent group structure has great influence on the extraction and separation ability of amide extractant. In this paper, four different extractants with different structures, namely TODGA (N,N,N’,N’-tetraoctyl-3-oxa-diglycolamide), T2EHDGA (N,N,N’,N’-tetraisooctyl-3-oxa-diglycolamide), DPDODGA (N,N’-dipropyl-N,N’-dioctyl-3-oxa-diglycolamide) and DIPDODGA (N,N’-diisopropyl-N,N’-dioctyl-3-oxa-diglycol-amide) were investigated. The extraction ability of rare earth elements in nitric acid system was investigated to understand the relationship between chemical structure of the extractant and the extraction and separation properties of rare earth ions. The effects of nitric acid acidity, rare earth metal ion concentration and extractant concentration on the extraction were also investigated.