Matrix Compositions Research Articles

Effect of deflocculants on the rheological behavior of high alumina matrix suspensions for self-flowing bauxite castable

This study investigates the influence of commercially available polyphosphates and polycarboxylate ethers as deflocculants on aqueous suspensions containing high alumina cement (HAC), reactive alumina (RA), and various matrix compositions. Utilizing rheological methods, the research explores the interplay between dispersant concentration and the apparent viscosity and flow behavior of RA suspensions and matrix mixtures. The Casson model is employed to effectively describe the obtained flow data. Moreover, the study discerns specific impacts of polycarboxylate ethers on the thickening properties of matrix mixtures characterized by varying RA and HAC contents. Additionally, the research evaluates the physical and mechanical properties of low-cement bauxite castables treated with a range of polycarboxylate esters. The findings demonstrate that all deflocculated suspensions exhibit Non-Newtonian structured fluid behavior with a discernible yield stress (τ0) at shear rates below 20 s-1. At higher shear rates, there is a significant reduction in apparent viscosity, aligning well with the Casson model. Comparative assessments, based on flow curve values τ0, elucidate differing degrees of suspension flocculation depending on the type of dispersant used.

A 3D printed dual screen-printed electrode separation device for twin electrochemical mini-cell establishment.

We describe a tiny 3D-printed polymethyl-methacrylate-based plastic sleeve that houses two disposable screen-printed electrodes (SPE) and enables each of the working electrodes (WEs) to work independently, on a different side of a thin barrier, in its own electrochemical (EC) mini-cell, while the SPE counter and reference units are shared for electroanalysis. Optical and EC performance tests proved that the plastic divider between WE1 and WE2 efficiently inhibited solution mixing between the mini-cells. The two neighboring, independently operating mini-cells enabled matched differential measurements in the same sample solution, a tactic designed for elimination of electrochemical interference in complex samples. In a proof-of-principle glucose biosensor trial, a glucose oxidase-modified WE2 and an unmodified WE1 delivered the EC data for the removal of anodic ascorbic acid (AA) interference simply by subtracting the WE1 (background) current from the analyte-specific WE2 current (from buffered sample solution supplemented with glucose/AA), at an anodic H2O2 detection potential of +1 V. The microfabricated SPE accessory is cheap and easy to make and use. For the many dual electrode SPE strips on the market for multiple analytical targets the new device widens the options for their exploitation in assays of biological and environmental samples with complex matrix compositions and significant risks of interference.

Investigation of nanostructured lipid carriers for fast intracellular localization screening using the Echo liquid handler

In the field of precision medicine, therapy is optimized individually for each patient, enhancing efficacy while reducing side effects. This involves the identification of promising drug candidates through high-throughput screening on human derived cells in culture. However, screening of drugs which have poor solubility or permeability remains challenging, especially when targeting intracellular components. Therefore, encapsulation of drugs into advanced delivery systems such as nanostructured lipid carries (NLC) becomes necessary. Here we show that the cellular uptake of NLC with different matrix compositions can be assessed in a high-throughput screening system based on acoustic droplet ejection (ADE) technology (Echo liquid handler). Our findings indicate that surface tension and viscosity of the NLC dispersions need to be tailored to enable a reliable ADE transfer. The automated NLC uptake studies indicated that the composition of the matrix, more specifically the amount of oleic acid, significantly influenced cellular uptake. The data obtained were corroborated by imaging based and spectral flow cytometry cellular uptake studies. These findings thus not only provide the basis for a screening tool to rapidly identify the efficacy of NLC uptake but also enable a next step toward precision high-throughput drug screening under consideration of an optimized drug delivery system.

Hydrogel Applications in Nitrogen and Phosphorus Compounds Recovery from Water and Wastewater: An Overview

This article provides an overview of the diverse applications of hydrogels in nutrient recovery from water and wastewater. Due to their unique properties, such as high water-retention capacity, nutrient rerelease, and tunable porosity, hydrogels have emerged as promising materials for efficient nutrient capture and recycling. It has been suggested that hydrogels, depending on their composition, can be reused in agriculture, especially in drought-prone areas. Further research paths have been identified that could expand their application in these regions. However, the main focus of the article is to highlight the current gaps in understanding how hydrogels bind nitrogen and phosphorus compounds. The study underscores the need for research that specifically examines how different components of hydrogel matrices interact with each other and with recovered nutrients. Furthermore, it is essential to assess how various nutrient-recovery parameters, such as temperature, pH, and heavy metal content, interact with each other and with specific matrix compositions. This type of research is crucial for enhancing both the recovery efficiency and selectivity of these hydrogels, which are critical for advancing nutrient-recovery technologies and agricultural applications. A comprehensive research approach involves using structured research methodologies and optimization techniques to streamline studies and identify crucial relationships.

Cutibacterium acnes biofilm formation is influenced by bone microenvironment, implant surfaces and bacterial internalization

BackgroundThe bacterial persistence, responsible for therapeutic failures, can arise from the biofilm formation, which possesses a high tolerance to antibiotics. This threat often occurs when a bone and joint infection is diagnosed after a prosthesis implantation. Understanding the biofilm mechanism is pivotal to enhance prosthesis joint infection (PJI) treatment and prevention. However, little is known on the characteristics of Cutibacterium acnes biofilm formation, whereas this species is frequently involved in prosthesis infections.MethodsIn this study, we compared the biofilm formation of C. acnes PJI-related strains and non-PJI-related strains on plastic support and textured titanium alloy by (i) counting adherent and viable bacteria, (ii) confocal scanning electronic microscopy observations after biofilm matrix labeling and (iii) RT-qPCR experiments.ResultsWe highlighted material- and strain-dependent modifications of C. acnes biofilm. Non-PJI-related strains formed aggregates on both types of support but with different matrix compositions. While the proportion of polysaccharides signal was higher on plastic, the proportions of polysaccharides and proteins signals were more similar on titanium. The changes in biofilm composition for PJI-related strains was less noticeable. For all tested strains, biofilm formation-related genes were more expressed in biofilm formed on plastic that one formed on titanium. Moreover, the impact of C. acnes internalization in osteoblasts prior to biofilm development was also investigated. After internalization, one of the non-PJI-related strains biofilm characteristics were affected: (i) a lower quantity of adhered bacteria (80.3-fold decrease), (ii) an increase of polysaccharides signal in biofilm and (iii) an activation of biofilm gene expressions on textured titanium disk.ConclusionTaken together, these results evidenced the versatility of C. acnes biofilm, depending on the support used, the bone environment and the strain.

Multi-functional amorphous/crystalline interfaces rendering strong-and-ductile nano-metallic-glass/aluminum composite

Metal matrix composites (MMCs) are the materials-of-choice for a large range of important applications under harsh service conditions. However, owing to the high phase contrast between the matrix and the reinforcements, the strength-ductility conflict of MMCs is still outstanding. Here we fabricated a novel aluminum (Al) matrix composite reinforced by deformable, cobalt-zirconium-boron (CoZrB) metallic glass nanoparticles. The amorphous CoZrB/Al composite with only 2.0 vol.% particle reinforcements possessed a uniaxial tensile strength of 387.0 ± 1.2 MPa, showing over 80 % improvement over the unreinforced pure Al matrix at a similar uniform elongation. The strength-ductility synergy of the composite was also significantly superior to that of the composite reinforced by fully crystallized nanoparticles. These findings were rationalized by the unique multi-functionality of the amorphous particle/matrix interfaces, which effectively transferred the load from the matrix to the particles, coordinated the co-deformation of the nanoparticles and the matrix, and imparted a transgranular fracture mode in the composite with extensive matrix plastic deformation. The methodology developed in this study was shown to be generally effective for other matrix and metallic glass nanoparticle compositions, and our work may shed new light on the development of high-performance metal matrix composites for advanced structural applications.

Investigation and performance analysis of eco-friendly coco fiber concrete hybridized with CNT blend

With the development of the technical trend, concrete using waste alternate material instead of sand material found economic potential for good structural behaviour. Besides, the susceptible crack, low strength-to-weight ratio, and low compressive strength are the reasons for shrinkage. Due to this reason, the investigation aims to limit the shrinkage under live load and increase the compression and flexural strength by the introduction of coconut waste chopped fiber (wCF), waste fly ash (wFA), and carbon nanotube powder (CNT) blended with conventional Portland paste. The developed concrete consists of 5 wt% wCF, 10 wt% wFA, and 0, 5, 10, and 15 wt% of CNT and is subjected to X-ray diffraction analysis, bulk density, compression and flexural strength, and water absorption studies. The X-ray diffraction pattern revealed the wCF, wFA, CNT, and matrix compositions. The concrete developed with 5 wt% wCF, 10 wt% wFA, and 15 wt% CNT cured within 28 days recorded maximum behaviour of compression strength (47 ± 1.8 MPa), flexural strength (4.9 ± 0.19 MPa), and water absorption of (2.8 ± 0.05 %).

Facile and fast elemental analysis using glass fiber filter by X-ray fluorescence

Analysis of elements in liquid samples via X-ray fluorescence (XRF) faces challenges due to diverse matrix effects. To address this, the use of glass fiber filters (GFFs) as effective substrates for XRF analysis was explored. The matrix compositions of various commercial GFFs were comprehensively analyzed and compared to assess their applicability in liquid analysis. Most GFFs do not contain heavy elements, exhibit highly consistent filter weights, and have matrix element contents with relative standard deviations (RSDs) below 3%, which are ideal for detecting heavy elements. GFFs were also demonstrated to have superior analytical sensitivity compared to alternative filters. Optimal analytical performance can be achieved by utilizing a 30 mm sample holder, dripping 50 μL of the sample on the uniformly pressed GFFs, and drying it via infrared heating. Most heavy elements showed wide linear concentration ranges spanning over three orders of magnitudes and limits of detection (LOD) lower than mg/L. The results of standard addition and recoveries in natural lake water were promising. Furthermore, GFFs proved capable of verifying the composition and quality of particulate materials. The used GFFs can also be easily regenerated through acid washing for reuse. Therefore, GFFs are optimal XRF substrates for analyzing liquid samples containing heavy metal ions and materials.

Multi-Emission Carbon Dots Combining Turn-On Sensing and Fluorescence Quenching Exhibit Ultrahigh Selectivity for Mercury in Real Water Samples.

Mercury is a ubiquitous heavy-metal pollutant and poses serious ecological and human-health risks. There is an ever-growing demand for rapid, sensitive, and selective detection of mercury in natural waters, particularly for regions lacking infrastructure specialized for mercury analysis. Here, we show that a sensor based on multi-emission carbon dots (M-CDs) exhibits ultrahigh sensing selectivity toward Hg(II) in complex environmental matrices, tested in the presence of a range of environmentally relevant metal/metalloid ions as well as natural and artificial ligands, using various real water samples. By incorporating structural features of calcein and folic acid that enable tunable emissions, the M-CDs couple an emission enhancement at 432 nm and a simultaneous reduction at 521 nm, with the intensity ratio linearly related to the Hg(II) concentration up to 1200 μg/L, independent of matrix compositions. The M-CDs have a detection limit of 5.6 μg/L, a response time of 1 min, and a spike recovery of 94 ± 3.7%. The intensified emission is attributed to proton transfer and aggregation-induced emission enhancement, whereas the quenching is due to proton and electron transfer. These findings also have important implications for mercury identification in other complex matrices for routine, screening-level food safety and health management practices.

Mechanisms of secondary biogenic coalbed methane formation in bituminous coal seams: a joint experimental and multi-omics study.

Coal seam microbes, as endogenous drivers of secondary biogenic gas production in coal seams, might be related to methane production in coal seams. In this study, we carried out anaerobic indoor culture experiments of microorganisms from three different depths of bituminous coal seams in Huainan mining area, and revealed the secondary biogas generation mechanism of bituminous coal seams by using the combined analysis of macro-genome and metabolism multi-omics. The results showed that the cumulative mass molar concentrations (Molality) of biomethane production increased with the increase of the coal seam depth in two consecutive cycles. At the genus level, there were significant differences in the bacterial and archaeal community structures corresponding to the three coal seams 1#, 6#, and 9#(p < 0.05). The volatile matter of air-dry basis (Vad) of coal was significantly correlated with differences in genus-level composition of bacteria and archaea, with correlations of R bacterial = 0.368 and R archaeal = 0.463, respectively. Functional gene analysis showed that the relative abundance of methanogenesis increased by 42% before and after anaerobic fermentation cultivation. Meanwhile, a total of 11 classes of carbon metabolism homologues closely related to methanogenesis were detected in the liquid metabolites of coal bed microbes after 60 days of incubation. Finally, the fatty acid, amino acid and carbohydrate synergistic methanogenic metabolic pathway was reconstructed based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The expression level of mcrA gene within the metabolic pathway of the 1# deep coal sample was significantly higher than that of the other two groups (p < 0.05 for significance), and the efficient expression of mcrA gene at the end of the methanogenic pathway promoted the conversion of bituminous coal organic matter to methane. Therefore, coal matrix compositions may be the key factors causing diversity in microbial community and metabolic function, which might be related to the different methane content in different coal seams.

First-principles thermodynamics of precipitation in aluminum-containing refractory alloys

Materials for high-temperature environments are actively being investigated for deployment in aerospace and nuclear applications. This study uses computational approaches to unravel the crystallography and thermodynamics of a promising class of refractory alloys containing aluminum. Accurate first-principles calculations, cluster expansion models, and statistical mechanics techniques are employed to rigorously analyze precipitation in a prototypical senary Al–Nb–Ta–Ti–V–Zr alloy. Finite-temperature calculations reveal a strong tendency for aluminum to segregate to a single sublattice at elevated temperatures. Precipitate and matrix compositions computed with our ab-initio model are in excellent agreement with previous experimental measurements (Soni et al., 2020). Surprisingly, conventional B2-like orderings are found to be both thermodynamically and mechanically unstable in this alloy system. Complex anti-site defects are essential to forming a stable ordered precipitate. Our calculations reveal that the instability of B2 compounds can be related to a simple electron counting rule across all binary alloys formed by elements in groups 4,5, and 6. The results of this study provide viable routes toward designing high-temperature materials for deployment in extreme environments.

Microscopic FT-IR imaging-based meat and bone meal species discrimination using the screened matrix fragments-related spectral pixels and tableting pretreatment

This study proposes a novel microscopic FT-IR imaging-based analytical strategy for the discrimination of meat and bone meal (MBM) species. The feasibility of correlation coefficient and PLS-DA methods for the screening of bone and meat fragment-related spectral pixels in MBM microscopic FT-IR imaging was validated. Subsequently, PLS-DA models were established for MBM species-specific analysis based on the screened bone and meat fragment-related spectral pixels. Comparative analysis with the PLS-DA model using all FT-IR pixels demonstrated a significant improvement in the performance of the PLS-DA model based on the fused matrix fragment-related spectral pixels, achieving an accuracy of approximately 0.980. Furthermore, the proposed analytical strategy exhibited a time efficiency advantage with a consumption period of approximately 4.5 min, thereby ensuring high spectral technical efficiency. The findings of this study offer a theoretical basis for the spectral discrimination analysis of agricultural materials with complex matrix compositions.

The effect of depth-dependent carbonation on the interfacial strength between GFRP reinforcement bar and reactive magnesia cementitious composites

Reactive magnesia cement (RMC) is an emerging class of low-alkaline and CO2-sequestering binder, which can mitigate the deterioration of GFRP reinforcements induced by a high-alkaline environment, e.g., in Portland cement. This study investigated the slip behavior of GFRP rebar embedded in RMC composite, which varies with carbonation depth significantly. The variation of the interfacial bond was determined by a specially designed push-out test of the GFRP core; the variation of the carbonation degree and microstructure was examined by SEM-EDX, MIP, XRD, TGA, FTIR, and acid digestion tests. Both properties demonstrated a similar trend, decreasing rapidly with increasing depth. A new finite element model that considers the depth-dependency of the matrix compositions and the rebar-to-matrix interfacial bond is established. It can predict the constitutive bond-slip behavior of a long GFRP rebar embedded in an RMC composite with non-uniform carbonation.

A Study of The Sound Absorption Properties of Layered Composites on Chicken Feather Fibers

Biocomposites made from animal fibers have now been developed into alternative materials for room acoustics. This study presents a material study on the sound absorption ability of chicken feather fiber composites made experimentally by layered methods of various matrix compositions. Testing the absorbability of material sound using an Impedance tube or Kundt tube method (ISO 10543-2), at a frequency of 200 Hz to 1600 Hz (Medium Sounds). The results revealed that chicken feather fiber composites (CFFC) performed well in sound absorption when using a matrix made from starch. Chicken feather fiber composites (CFFC) perform well in the medium to high-frequency range and can be recommended as indoor sound-absorbing materials.

Nondestructive, quantitative viability analysis of 3D tissue cultures using machine learning image segmentation.

Ascertaining the collective viability of cells in different cell culture conditions has typically relied on averaging colorimetric indicators and is often reported out in simple binary readouts. Recent research has combined viability assessment techniques with image-based deep-learning models to automate the characterization of cellular properties. However, further development of viability measurements to assess the continuity of possible cellular states and responses to perturbation across cell culture conditions is needed. In this work, we demonstrate an image processing algorithm for quantifying features associated with cellular viability in 3D cultures without the need for assay-based indicators. We show that our algorithm performs similarly to a pair of human experts in whole-well images over a range of days and culture matrix compositions. To demonstrate potential utility, we perform a longitudinal study investigating the impact of a known therapeutic on pancreatic cancer spheroids. Using images taken with a high content imaging system, the algorithm successfully tracks viability at the individual spheroid and whole-well level. The method we propose reduces analysis time by 97% in comparison with the experts. Because the method is independent of the microscope or imaging system used, this approach lays the foundation for accelerating progress in and for improving the robustness and reproducibility of 3D culture analysis across biological and clinical research.

Dual-Sensitive Fluorescent Nanoprobes for Simultaneously Monitoring In Situ Changes in pH and Matrix Metalloproteinase Expression in Stiffness-Tunable Three-Dimensional In Vitro Scaffolds.

A tumor microenvironment often presents altered physicochemical characteristics of the extracellular matrix (ECM) including changes in matrix composition, stiffness, protein expression, pH, temperature, or the presence of certain stromal and immune cells. Of these, overexpression of matrix metalloproteinases (MMPs) and extracellular acidosis are the two major hallmarks of cancer that can be exploited for tumor detection. The change in matrix stiffness and the release of certain cytokines (TNF-α) in the tumor microenvironment play major roles in inducing MMP-9 expression in cancerous cells. This study highlights the role of mechanical cues in upregulating MMP-9 expression in cancerous cells using stiffness-tunable matrix compositions and dual-sensitive fluorescent nanoprobes. Ionically cross-linked 3D alginate/gelatin (AG) scaffolds with three stiffnesses were chosen to reflect the ECM stiffnesses corresponding to healthy and pathological tissues. Moreover, a dual-sensitive nanoprobe, an MMP-sensitive peptide conjugated to carbon nanoparticles with intrinsic pH fluorescence properties, was utilized for in situ monitoring of the two cancer hallmarks in the 3D scaffolds. This platform was further utilized for designing a 3D core-shell platform for spatially mapping tumor margins and for visualizing TNF-α-induced MMP-9 expression in cancerous cells.

A New Perspective on the Applicability of Diffuse Reflectance Spectroscopy for Determining the Hematite Content of Fe-Rich Soils in the Tropical Margins of China

Hematite and goethite are widely occurring chromogenic iron oxides in soils and sediments that are sensitive to climatic dry/wet shifts. However, only by accurately quantifying the content or ratio of hematite and goethite can they be applied reliably to palaeoclimate reconstruction. Compared to the Loess Plateau of China, hematite in the soils of southern China has not been sufficiently studied. We used diffuse reflectance spectroscopy (abbreviation DRS, including the first-derivative curves and the second-derivative curves of the Kubelka–Munk remission functions), combined with ignition at 950 °C, and X-ray fluorescence (XRF) to quantify the hematite content of four tropical-margin iron-rich soil profiles with different matrix compositions in the Leizhou Peninsula, China. We also examined the application of hematite quantification parameters in soils with different matrix compositions under the same climatic conditions. Our main findings are as follows: (i) DRS first-derivative curves can reflect the presence of goethite and hematite in soils, and their relative contents can be compared within the same profile. (ii) The second-derivative curve of the Kubelka–Munk remission functions can reflect the relative proportions of goethite and hematite and provide information about the degree of Al substitution. (iii) Combined with calibration equations, soil redness can reliably quantify the hematite content, but it is necessary to consider the effect of mucilage envelopes in the process of hematite formation. Additionally, we summarize various methods used for quantifying hematite, and the influence of soil matrix compositions, with the aim of providing a reference for hematite quantification elsewhere. We also propose a new indicator (ΔHmRed/HmRed) to help detect iron hydroxide/iron oxide changes in soils.

Improved mRNA affinity chromatography binding capacity and throughput using an oligo-dT immobilized electrospun polymer nanofiber adsorbent

Increased demand for mRNA-based therapeutics and improved in vitro transcription (IVT) yields have challenged the mRNA purification platform. Hybridization-affinity chromatography with an immobilized oligo-deoxythymidilic acid (oligodT) ligand is often used to capture mRNA through base pairing with the polyadenylated tail. Commercially available oligodT matrices include perfusive cross-linked poly(styrene-divinylbenzene) 50 µm POROS™ chromatography resin beads and convective polymethacrylate CIMmultus® monolithic columns consisting of 2 µm interconnected channels. POROS™ columns may be limited by poor mass transfer for larger mRNAs and slow flowrates, while monoliths can operate at higher flowrates but are limited by modest binding capacity. To enable both high flowrates and binding capacity for mRNA of all lengths, prototype chromatography media was developed by Cytiva using oligodT immobilized electrospun cellulose nanofibers (Fibro™) with a 0.3–0.4 µm pore size. In this work, four polyadenylated mRNAs ranging from ∼1900–4300 nucleotides were used to compare the dynamic binding capacity (DBC) of Fibro™, POROS® and CIMmultus® columns as a function of residence time and binding buffer compositions. Fibro™ improved the DBC ∼2–4-fold higher than CIMmultus® and ∼2–13-fold higher than POROS™ across all residence times, mRNA length, and binding matrix compositions tested. CIMmultus® DBC was least dependent on residence time and mRNA size, while both Fibro™ and POROS™ DBC increased at slower flowrates and with shorter mRNA. Surprisingly, inverse size exclusion (ISE) experiments showed that POROS™ was not limited by diffusion and POROS™ along with CIMmultus® demonstrate higher mRNA permeation however the Fibro™ prototype is not in the final configuration. Lastly, IVT reaction products were subjected to purification and oligodT elution product yield, quality, and purity were consistent across the three matrices investigated. These results highlight the benefits of high DBC and equivalent product profiles offered by the oligodT Fibro™ prototype compared to commercially available oligodT media.

3D BIOPRINTING TISSUE-ENGINEERED MENISCAL CONSTRUCTS

Meniscal injuries affect over 1.5 million people across Europe and the USA annually. Injury greatly reduces knee joint mobility and quality of life and frequently leads to the development of osteoarthritis. Tissue engineered strategies have emerged in response to a lack of viable treatments for meniscal pathologies. However, to date, constructs mimicking the structural and functional organisation of native tissue, whilst promoting deposition of new extracellular matrix, remains a bottleneck in meniscal repair. 3D bioprinting allows for deposition and patterning of biological materials with high spatial resolution. This project aims to develop a biomimetic 3D bioprinted meniscal substitute.Meniscal tissue was characterised to effectively inform the design of biomaterials for bioprinting constructs with appropriate structural and functional properties. Histology, gene expression and mass spectrometry were performed on native tissue to investigate tissue architecture, matrix components, cell populations and protein expression regionally across the meniscus. 3D laser scanning and magnetic resonance imaging were employed to acquire the external geometrical information prior to fabrication of a 3D printed meniscus. Bioink suitability was investigated through regional meniscal cell encapsulation in blended hydrogels, with the incorporation of growth factors and assessed for their suitability through rheology, scanning electron microscopy, histology and gene expression analysis.Meniscal tissue characterisation revealed regional variations in matrix compositions, cellular populations and protein expression. The process of imaging through to 3D printing highlighted the capability of producing a construct that accurately replicated meniscal geometries. Regional meniscal cell encapsulation into hydrogels revealed a recovery in cell phenotype, with the incorporation of growth factors into the bioink's stimulating cellular re-differentiation and improved zonal functionality.Meniscus biofabrication highlights the potential to print patient specific, customisable meniscal implants. Achieving zonally distinct variations in cell and matrix deposition highlights the ability to fabricate a highly complex tissue engineered construct.Acknowledgements: This work was undertaken as part of the UK Research and Innovation (UKRI)-funded CDT in Advanced Biomedical Materials.

Synthesis and luminescence characteristics of yttrium, aluminum and lanthanum borates doped with europium ions (Eu 3+)

Inorganic materials doped with rare earth (RE) ions are an object of intense research due to their optical and electrical properties. These materials have the potential for various applications, such as solid-state lasers, active planar waveguides, optical fiber amplifiers, light-emitting diodes (LEDs), displays, ink fillers, security features, etc. RE trivalent ions can emit light from the ultraviolet (UV) to the near-infrared (NIR) regions due to electronic transitions of the 4f-5d levels. Yttrium borate doped with europium ions was prepared by solid-state synthesis in a muffle furnace at 900oC for 4 hours, while lanthanum and aluminum borates doped with europium ions were prepared at 1000oC for 6 hours again in a muffle furnace. The resulting materials are fine white powders. Among the rare earth ions, europium is one of the most commonly used activators because the ions of Eu3+ and Eu2+ can be used as emission sites in the host lattices. Eu3+ ions can produce effective sharp emission peaks in different matrix compositions. Photoluminescence analysis of the samples was performed, based on which the luminescence intensity of the Eu3+ ion was determined through a comparative characteristic. YBO3:Eu3+ phosphor is optically active and chemically stable. It is characterized by a strong orange-red emission at ≈ 591 nm, ≈ 612 and ≈ 696 nm due to the 5D0→7F1 and 5D0→7F2 electronic transitions, respectively. Red emission is also observed for LaBO3:Eu3+ at ≈ 592 and ≈ 615 nm, characterizing the 5D0→7F1 and 5D0→7Fj (j=0, 1, 2, 3, 4) transitions. While aluminum borate doped with europium ion shows intense emission at ≈ 612 nm, making this material suitable for lighting devices. The technique of Fourier transform infrared spectroscopy (FTIR) was used to study the structure of the obtained materials.