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Photochemical valence bond isomerization of a crystalline Dewar benzene (DB) diacid monoanion salt with an acetophenone-linked piperazinium cation that serves as an intramolecular triplet energy sensitizer (DB-AcPh-Pz) exhibits a quantum chain reaction with as many as 450 product molecules per photon absorbed (Φ ≈ 450). By contrast, isomorphous crystals of the DB diacid monosalt of an ethylbenzene-linked piperazinium (DB-EtPh-Pz) lacking a triplet sensitizer showed a less impressive quantum yield of ca. Φ ≈ 22. To establish the critical importance of a triplet excited state carrier in the adiabatic photochemical reaction we prepared mixed crystals with DB-AcPh-Pz as a dilute triplet sensitizer guest in crystals of DB-EtPh-Pz. As expected from their high structural similarities, solid solutions were easily formed with the triplet sensitizer salt in the range of 0.1 to 10%. Experiments carried out under conditions where light is absorbed by the triplet sensitizer-linked DB-AcPh-Pz can be used to initiate a triplet state adiabatic reaction from 3DB-AcPh-Pz to 3HB*-AcPh-Pz, which can serve as a chain carrier and transfer energy to an unreacted DB-EtPh-Pz where exciton delocalization in the crystalline solid solution can help carry out an efficient energy transfer and enable a quantum chain employing the photoproduct as a triplet chain carrier. Excitation of mixed crystals with as little as 0.1% triplet sensitizer resulted in an extraordinarily high quantum yield Φ ≈ 517.

In this study, SrY₂O₄:Dy³⁺ phosphors were synthesized using the solid-state reaction method and evaluated after heat treatment at 1300 °C for 5 h. XRD analysis confirmed the orthorhombic structure of SrY₂O₄ with residual Y₂O₃ present. The addition of Dy³⁺ ions caused lattice expansion, impacting grain size and crystallinity. SEM images showed that the phosphor particles had irregular shapes with minimal size variation, although they tended to agglomerate due to high-temperature heat treatment. Optical analysis revealed significant absorption and emission peaks, with a strong excitation band in the 200–306 nm range and prominent sharp peaks in the 306–480 nm range, particularly at a 0.5 mol% doping concentration. Emission spectra indicated the highest intensity at 0.5 mol% Dy³⁺ concentration, with intensity decreasing due to concentration quenching at higher levels. Thermal stability tests showed peak emission intensity at 70 °C, with stability maintained up to 190 °C before notable thermal quenching. Chromaticity coordinates remained within the warm white region at both temperatures. This study provides detailed insights into the effects of Dy³⁺ doping on the structural, optical, and thermal properties of SrY₂O₄ phosphors. Compared to previous studies on rare-earth-doped SrY₂O₄ phosphors, this work is the first to systematically explore the substitution of Y³⁺ ions with Dy³⁺ ions until full replacement. The study not only confirmed that the highest emission intensity occurs at 0.5 mol% Dy³⁺ concentration, but also demonstrated that Dy³⁺-doped SrY₂O₄ phosphors exhibit excellent thermal stability, with emission stability maintained below 150 °C. These findings expand the potential applications of Dy³⁺-doped SrY₂O₄ phosphors, particularly in high-temperature environments and solid-state lighting. [ABSTRACT FROM AUTHOR]

Monoclinic barium aluminosilicate (celsian) shows application potential owing to its high-temperature resistance, low thermal conductivity, and excellent oxidative reduction properties. Hexacelsian can easily undergo nucleation because of its favorably symmetric crystal structure, resulting in faster precipitation compared to than in the case of celsian. Celsian can only be formed through the sluggish transformation of hexacelsian at high temperatures. In this study, celsian doped with different contents of CaO was synthesized through a simple one-step solid-state reaction process at lower temperatures and in a shorter time and investigated using differential thermal analysis, phase characterization, microstructural observation, and FactSage thermodynamic calculations. Results showed that the addition of CaO could promote the solid-state reaction, affording products such as barium silicate, hexacelsian, and celsian at lower temperatures. Moreover, CaO could promote the synthesis of celsian in the form of solid solution, affording fully monoclinic celsian Ba 0.7 Ca 0.3 Al 2 Si 2 O 8 with only 3 h of holding time at 1400 °C. The optimal addition of CaO showed a decreasing trend with the increase in heat treatment temperature. An optimum CaO level of 0.1 ≤ x ≤ 0.3 was recommended to stabilize celsian. The effects of CaO addition and temperature on the physical, mechanical and thermal conductivity properties of Ba 1-x Ca x Al 2 Si 2 O 8 were investigated, and Ba 1-x Ca x Al 2 Si 2 O 8 also exhibited excellent antioxidant reduction properties. [ABSTRACT FROM AUTHOR]

M9‐ and M12‐metal clusters appear as face‐sharing double‐clusters in (Pb9Br19)2(Pb1.5Br2)2(melem)3(6) and as triple‐clusters in (Pb12Br25)4(Pb1.67Br2)3(melem)4(7). All compounds are characterized by single‐crystal and powder X‐ray diffraction, and further validated by infrared (IR) spectroscopy and 207Pb and 79/81Br NMR studies on (5). Photoluminescence studies on compound (6) reveal emission at 430 nm while the emission of (5) is completely quenched. [ABSTRACT FROM AUTHOR]

Nanomaterials exhibit properties not seen in large-scale materials; therefore, they have been developed for different applications. Top-down and bottom-up approaches are used to design and fabricate composite materials. Electrostatic assembly (ESA) is a bottom-up approach to material design. In this study, SiO2‒SiO2 composite nanoparticles were selected as a model to demonstrate the feasibility of fabricating composite particles via ESA. In addition, researchers have been studying the fabrication of high-density Al2O3 (which has a theoretical density of approximately 3.95 g ml− 1) at moderate temperatures for a long time. In this study, composite particles consisting of small Al2O3 particles (low sintering temperature) surrounding large Al2O3 particles (high sintering temperature) were fabricated via ESA. The sintered bodies of Al2O3 composite particles obtained at 1350 °C for 2 h had a density of approximately 3.0 g cm− 3, which exceeded that of sintered bodies of only high-temperature-sintered Al2O3 (2.8 g cm− 3). [ABSTRACT FROM AUTHOR]

Geopolymer matrix composites (GMCs) are actively being developed for high‐temperature applications. In this work, we investigated different composite preparation parameters, such as the elaboration conditions (time, temperature and pressure) and composite dimensions (number of folds and surface area). In addition, we studied the effect of alkali cations (NaK or K), on metakaolin based geopolymer matrix composition, and textile type (N312, N610) of the composites on fiber–matrix interactions in high‐temperature geopolymer composites and their flexural behavior. The process we ultimately selected was as follows: an 8.5‐fold composite of surface area 100 cm2 was pressed for 2 h at 120°C. After thermal treatment at 1150°C, composites containing the N312 textile with B2O3 showed greater heterogeneity, viscous flow and lower flexural strength (7 MPa) due to fiber–matrix interactions. In contrast, above 1150°C, composites with the N610 textile had no fiber–matrix interactions and showed greater flexural strength (51 MPa). The specific flexural strength correlated well with the overmodifying element ratio based on the composite composition. In fact, the presence of viscous flow suggested that boron and some aluminum atoms could act as network modifiers. Thus, the two ratios were nSigeo+nAlgeonMgeo$$ \frac{{n\mathrm{Si}}_{\mathrm{geo}}+n{\mathrm{Al}}_{\mathrm{geo}}}{{n\mathrm{M}}_{\mathrm{geo}}} $$ or nSigeo+N312+nAlgeo×0.5+nAlN312nMgeo+nBN312+nAlgeo×0.5$$ \frac{{n\mathrm{Si}}_{\mathrm{geo}+\mathrm{N}312}+n{\mathrm{Al}}_{\mathrm{geo}}\times 0.5+{n\mathrm{Al}}_{\mathrm{N}312}}{{n\mathrm{M}}_{\mathrm{geo}}+{n\mathrm{B}}_{\mathrm{N}312}+{n\mathrm{Al}}_{\mathrm{geo}}\times 0.5} $$ depending on the presence of viscous flow. [ABSTRACT FROM AUTHOR]

Marble and granite industries have expanded significantly over the past few decades, leading to an increase in processing waste. To reduce the environmental impacts of granite and marble processing waste, proper management and potential recycling with sustainable methodologies are crucial. The aim of this study is to synthesize nano-calcium silicates by utilizing a fine fraction of waste derived from the granite (rich in SiO2) and the marble (rich in CaO) processing industries, using a chemical-free solid-state reaction method. The research investigates the effects of three different mix proportions of CaO:SiO2 (1:0.9, 1:1, 1:1.1) on calcium silicate production at a calcination temperature of 1000 ℃. Furthermore, calcium silicate is reduced to nano-size by adopting various milling time intervals (0, 4, 6, 8, 10 h) using a planetary ball mill. The results indicate that the mix proportion of 1:1 yields the highest amount of calcium silicate, and a milling time of 6 h yields the smallest particle size. The confirmation of calcium silicate (in this case, wollastonite) formation is verified using various analysis techniques, such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and Scanning electron microscopy (SEM). Particle size distribution analysis and transmission electron microscopy (TEM) show that the mean particle size is less than 100 nm, and Brunauer–Emmett–Teller (BET) analysis reveals a surface area of 6 m2/g. The study highlights that the solid-state reaction method might be a promising approach for effectively treating waste materials. [ABSTRACT FROM AUTHOR]

Rare-earth permanent magnets, such as Nd2Fe14B, have been widely used in electric vehicle and wind turbine motors due to their high anisotropy field (Ha), saturation magnetization (Ms) and coercivity (Hc). Cerium (Ce) has gained attention as a potential alternative to neodymium (Nd) due to its high abundance and low cost. The relatively poor intrinsic magnetic properties of Ce magnets, however, remain a significant challenge for their industrial applications. In this study, the synthesis of Ce-based RE2Fe14B (2-14-1) phases was achieved by a modified reduction-diffusion (R-D) process using REFeO3 (RE = Ce, Nd) as a precursor. The precursor was prepared by a solid-state reaction with CeO2, Nd2O3, Fe2O₃ and Fe powders, which is a much more suitable process for mass production and cost-effectiveness. Optimal composition and heat treatment conditions enabled the formation of single-phase Ce-based 2-14-1 particles. The as-synthesized single-phase Ce2Fe14B particles exhibited an Ms value of ~120 emu/g and an intrinsic coercivity (Hci) value of ~85 Oe, which can be attributed to the large particle size as observed by FE-SEM. [ABSTRACT FROM AUTHOR]

This study focused on achieving high ionic conductivity in Li-La-TiO (LLTO) solid electrolyte. To enhance ionic conductivity, the synthesis reaction was optimized by controlling the composite crystal structure of TiO2 at the B-site of the perovskite (ABO3) structured LLTO, incorporating rutile, brookite, and anatase phases. The solid-phase LLTO, synthesized utilizing the core – shell structured composite-phase TiO2 developed in this study for the first time, successfully transformed its crystal structure to β-LLTO (tetragonal to cubic). This resulted in a significant improvement in ionic conductivity (i.e. 1.11 × 10−4 Scm−1). The study findings confirmed that the composite crystal structure TiO2 used in the solid-phase synthesis of LLTO induced an increase in oxygen vacancies during the synthesis process, thereby reducing the step-free energy required for the final synthesis. [ABSTRACT FROM AUTHOR]

Ce(2-x–y)GdxDyyO2-δ nanoparticles with x = 0.02 and y = 0.02, 0.04, 0.06, and 0.08 with a size range of 15.81 to 40.42 nm have been obtained by annealing the solid-state reaction-derived nanocrystalline powders. Correlations between Gd and Dy doping and lattice expansion were found; lattice parameters increased from 5.423 to 5.468 Å. When Gd and Dy content increased, optical investigations showed unexpected bandgap behaviour that did not follow the predicted reduction. Red, green, blue, and violet emissions have been identified via photoluminescence analysis. SEM and EDS verified the homogenous elemental distribution of spherical nanoparticles. With a growing magnetic moment and coercive field, magnetic measurements showed paramagnetic activity. [ABSTRACT FROM AUTHOR]

High-entropy perovskite ceramics (HEPCs) with equal atomic ratios have recently emerged as a highly promising class of materials due to their unique magnetic properties. However, the crystal structure, microstructure and magnetic properties of unequal atomic ratios HEPCs have yet to be fully investigated. In this paper, single-phase HEPCs (La 0.25 Nd 0.25 Sm 0.25 Gd 0.25) 1- x Ho x MnO 3 ((LNSG) 1- x H x MO) have been synthesized using solid-state reactions. The effect of Ho element content (x = 0.25, 0.3, 0.35 and 0.4) on the structure and magnetic properties was systematically investigated. All samples exhibit an orthorhombic perovskite structure with a Pbnm space group and show obvious crystallization characteristics after sintering at 1250 °C for 16 h (LNSG) 1- x H x MO HEPCs display a smooth surface texture and distinct grain boundaries, as well as significant hysteresis effects at T = 5 K. The spin-orbit interaction and magnetic anisotropy between Ho and Mn ions increase with the increase of Ho content, which increases the saturation magnetization (M s) of HEPCs. (LNSG) 0.6 H 0.4 MO exhibits the lowest magnetic hysteresis losses among the considered samples, attributed to its highest M s (50.95 emu/g) and the lowest coercivity H c (0.6 kOe). These characteristics endow it with a potential application in magnetic storage devices. [ABSTRACT FROM AUTHOR]

W-type Ba-hexaferrite, BaZn2−xCoxFe16O27, was synthesized via both conventional solid-state (x = 0.4, 0.5, 0.6, 0.75, 1.0, 1.25, 1.5) and molten-salt methods (x = 0.75, 1.0, 1.25). The structure, electromagnetic (EM) properties, and EM wave absorption characteristics were examined across a frequency range of 0.1–18 GHz, focusing on the influence of varying x. As x increased from 0.4 to 0.75, the magnetic anisotropy field (Hani) decreased, reaching its minimum at x = 0.75, before rising again as x continued to increase up to 1.5. Hani was found to be proportional to the ferromagnetic resonance (FMR) frequency, allowing for the tuning of the EM wave absorption frequency range. W-type hexaferrite–epoxy composites (10 wt%) with x values between 0.6 and 1.5 exhibited outstanding wideband EM wave absorption, with a maximum absorption (RLmin < −50 dB) and a wide absorption bandwidth where RL < −10 dB extended beyond 10 GHz (Δfwb > 10 GHz). The x = 1.25 sample with a thickness of 2.37 mm achieved RLmin = −69 dB at 7.8 GHz, while the x = 1.0 sample with a thickness of 2.33 mm delivered Δfwb = 12.5 GHz (5.1–17.6 GHz). Samples synthesized via the molten-salt method showed larger plate-like grain growth compared to those produced by the solid-state method, with permeability spectra shifting to lower frequencies, consequently lowering the EM wave absorption band. [ABSTRACT FROM AUTHOR]

A ceramic material consisting of a binary oxide of zirconium and titanium, with a composition of titanium dioxide (TiO2)0.15 doped with zirconium dioxide (ZrO2)0.85, was synthesized using a solid-state reaction method and sintered at different temperatures such as room temperature, 800, 900, 1100, and 1200 °C. X-ray diffraction (XRD) technique was employed to ascertain the grain size, d-spacing, dislocation density, and microstrain values. The synthesis of the samples revealed that the zirconium phase exhibited predominantly monoclinic characteristics up to a temperature of 1100 °C. However, a mixed phase consisting of monoclinic and tetragonal phases was found at the temperature of 1200 °C. The shift toward lower angle sides of the maximum intensity peak was seen with increased sintering temperature. The optical characteristics of synthesized pure zirconium and TiO2-doped ZrO2 nanoparticles were examined using UV–Vis diffuse absorption spectroscopy. The sintering temperature directly impacted the band gap, resulting in a drop from 5.44 to 5.24 eV. The research explored the relationship between the synthesized nanoparticles' frequency and dielectric properties such as dielectric constant, dielectric loss, and AC electrical conductivity. The dielectric constant and dielectric loss of ZrO2 doped with TiO2 demonstrated a significant decrease with increasing frequency. The phenomenon being discussed is widely recognized in the scientific community as Maxwell–Wagner polarization, following the theoretical framework put forward by Koop. The dielectric constant values observed in the unsintered samples were more significant than those observed in the sintered samples. [ABSTRACT FROM AUTHOR]

Heating of powders of linear dipeptides can give their cyclic analogs with practically useful properties. No solvents are used, and the product yield can be close to 100%. However, this method for obtaining relatively expensive cyclic dipeptides remains poorly understood. In the present work, thermally induced reactions of cyclization of L-phenylalanyl-L-alanine and L-alanyl-L-phenylalanine in the solid state are investigated for the first time using approaches of the non-isothermal kinetics. Kinetic parameters, including the activation energy and Arrhenius factor of these reactions, were estimated. It was shown that the sequence of amino acid residues in the molecules of the studied dipeptides affects the kinetic parameters of cyclization. The results obtained in the present work allow us to predict the preferred order of such residues in the dipeptide, providing the lowest activation energy for the reaction of their cyclization. This will be useful in developing strategy to the synthesis of biologically active derivatives of diketopiperazines. [ABSTRACT FROM AUTHOR]

The novel double perovskite oxide SrEuTiFeO6 was synthesized using the solid‐state reaction method. X‐ray diffraction analysis, complemented by Rietveld refinement, confirmed that this material crystallizes in a cubic double perovskite structure with the Pm3̅m space group and revealed cationic disorder at both the A (Sr, Eu) and B (Ti, Fe) sites. Crystallite size and lattice strain were determined through various methods. Fourier‐transform infrared spectroscopy was utilized to examine vibrational modes and bond distortions within this material. Scanning electron microscopy showed a heterogeneous microstructure, with a wide distribution of grain sizes and shapes, resulting from the kinetics of the solid‐state synthesis. Energy dispersive X‐ray spectroscopy confirmed the material's homogeneity, stoichiometry, and chemical composition. UV–visible spectroscopy was used to investigate the optical properties of SrEuTiFeO6, identifying several characteristic optical transitions. The band gap energy and refractive index were found to be 2.08 eV and 2.60, respectively, indicating the material's potential for various applications. Additionally, the dielectric properties, including the relative dielectric constant and loss tangent, were thoroughly analyzed as functions of frequency and temperature. The electrical conductivity dispersion phenomenon was also analyzed according to Jonscher's power law, revealing the predominance of overlapping the large polaron tunneling mechanism. [ABSTRACT FROM AUTHOR]

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A designed anthracene‐based monomer for topochemical Diels–Alder cycloaddition polymerization crystallized with head‐to‐tail arrangement of molecules, as revealed by single‐crystal X‐ray diffraction (SCXRD) analysis. The diene and dienophile units of adjacent monomer molecules are aligned at an average distance of 4.6 Å, suggesting a favorable crystalline arrangement for their intermolecular Diels–Alder cycloaddition reaction to form a linear polymer. Surprisingly, heating the monomer crystals at a temperature above 125 °C resulted in the formation of intramolecular Diels–Alder cycloadduct, which could be characterized by various spectroscopy and SCXRD analysis. Various time‐dependent studies such as NMR, PXRD, and DSC, studies established that the reaction followed topochemical pathway. Schmidt's topochemical postulates are generally used to predict the topochemical reactivity and product, by analyzing the crystal structure of the reactant. Though the crystal arrangement predicted polymerization, upon heating, the molecule avoided this pathway by undergoing a large rotation to form an intramolecular cycloadduct. Theoretical calculations supported the feasibility of the rotation, exploiting the flexibility of the molecule and voids present. These findings caution that the reliance on Schmidt's criteria for topochemical reactions may sometimes be misleading, especially in heat‐induced reactions. [ABSTRACT FROM AUTHOR]

Ba3Ca2(PO4)3F, having been proven beneficial for ancient geological surveys, was also found to be an efficient fluorescence emitter when doped with various rare-earth and transition ions. Advancing the respective properties further, dysprosium (Dy3+) was added as an activator into the Ba3Ca2(PO4)3F host lattice. The Dy ion in its trivalent form possesses emission in two regions, blue at 481 nm and green at 575 nm, opening a new window towards its plausible use in white-light-emitting diode (LED) lighting appliances. Subsequent analyses including x-ray diffraction, Rietveld refinement, photoluminescence, and lifetime observed in milliseconds (ms) revealed a similar nature of the decay curves as given in the literature. Further, a CIE coordinate calculation predicted near-ideal white light emission. [ABSTRACT FROM AUTHOR]

This study focused on achieving high ionic conductivity in Li-La-TiO (LLTO) solid electrolyte. To enhance ionic conductivity, the synthesis reaction was optimized by controlling the composite crystal structure of TiO2 at the B-site of the perovskite (ABO3) structured LLTO, incorporating rutile, brookite, and anatase phases. The solid-phase LLTO, synthesized utilizing the core – shell structured composite-phase TiO2 developed in this study for the first time, successfully transformed its crystal structure to β-LLTO (tetragonal to cubic). This resulted in a significant improvement in ionic conductivity (i.e. 1.11 × 10−4 Scm−1). The study findings confirmed that the composite crystal structure TiO2 used in the solid-phase synthesis of LLTO induced an increase in oxygen vacancies during the synthesis process, thereby reducing the step-free energy required for the final synthesis.

In this report, I studied the structural, morphological, and dielectric properties of new ferroelectric compounds prepared according to the formula Ba0.95Sr0.05Ti1-ySnyO3. The solid-state reaction method enhanced by a high-efficiency metal ball mill was used in the preparation process. The quantitative and qualitative analysis of the XRD patterns confirmed the crystallization of the samples y = 0.00, 0.05 in the tetragonal crystal system and the presence of the tetragonal and cubic crystal systems together in the samples y = 0.10, 0.14. Formation of BaSnO3 impurities in very low percentages in the doped samples. Their prevalence increases with increasing tin content, reaching 8.7% at the ratio y = 0.14. SEM images of the ceramic samples showed the formation of nano-ceramics with a high degree of condensation at the doping ratio y = 0.05. The dielectric analyses showed high thermal stability in the dielectric properties of the ceramic samples y = 0.05, 0.10, which was shown by the flatness of the dielectric constant curve over the entire temperature range studied, where this stability is attributed to the structure of the nano-grains that resist the ferroelectric-paraelectric phase transition. Furthermore, the dielectric properties were interpreted by accurately linking the dielectric measurements with the nano-structural and polar properties.

Owing to their energy-saving and environmentally friendly characteristics, rare-earth-free ultraviolet-excited green-luminescent materials have garnered significant attention. To improve the luminescence efficiencies of green-luminescent materials, this study synthesized Ta-doped CsV 1-x O 3 green-light-emitting phosphors through a solid-state-reaction method, adopting an optimal Ta doping concentration of 10%. Theoretical calculations and reflection spectra revealed an intrinsic indirect band gap of 2.86 eV for CsV 0.9 Ta 0.1 O 3 , lower than that of CsVO 3 (3.63 eV). Under 365 nm excitation, the as-prepared phosphors exhibited broadband emissions ranging from 400 nm to 700 nm, attributed to the 3T 2 →1A 1 and 3T 1 →1A 1 transitions within VO 4 tetrahedra. Notably, adding Ta5+ ions to CsVO 3 increased its emission intensity by 1.39 times and induced a redshift in its excitation spectrum from 369 to 375 nm. Furthermore, Ta5+ doping significantly distorted the VO 4 tetrahedra and influenced the optical properties of the synthesized phosphors. Specifically, the nearest of Cs–V bond length increased, and weak interactions between V5+ ions and Cs + ions led to a 1.5-fold higher internal quantum efficiency (60.49%) of CsV 0.9 Ta 0.1 O 3 compared to that of CsVO 3. Furthermore, CsV 0.9 Ta 0.1 O 3 demonstrated high thermal stability, retaining 75.57% of its initial intensity even at 140 °C. Overall, these results indicate the potential applicability of CsV 0.9 Ta 0.1 O 3 as a green-emitting phosphor for white-light-emitting diode applications. [ABSTRACT FROM AUTHOR]

A series of Eu3+-doped self-activated Zn3(VO4)2 (x = 0.0, 2.0, 4.0, 6.0, 8.0 and 10.0 mol%) phosphors have been successfully synthesized by a high-temperature solid-state reaction method. Powder X-ray diffraction patterns of the samples were measured, indicating the successful formation of phosphors with orthorhombic crystal structure. Field emission scanning electron microscopy was used to evaluate the morphology and particle size of the prepared samples, and the composition was analysed by energy X-ray dispersion technique. In addition, prepared samples were analysed by characterization techniques such as transmission electron microscopy, Fourier transform infrared spectroscopy, UV diffuse reflectance spectroscopy and photoluminescence (PL). The PL properties of prepared samples show green–red emission at 395 nm excitation and strong red emission at 467 nm excitation. Under 395 nm excitation, PL emission shows broad green emission band due to self-luminescence properties of vanadate ions. With the doping of Eu3+ ions, (VO4)3– ions transfer their energy to Eu3+ ions. The highest red emission intensity was observed in 8 mol% Eu3+ concentration. The CIE spectral coordinates and colour-correlated temperature of the as-prepared Zn3(VO4)2:Eu3+ phosphors were studied in detail at various Eu3+ concentrations. The obtained PL results demonstrate that the as-prepared Zn3(VO4)2:Eu3+ phosphors can be investigated as green–orange–red emitting phosphors in the future for white light-emitting diodes applications. [ABSTRACT FROM AUTHOR]

In this report, I studied the structural, morphological, and dielectric properties of new ferroelectric compounds prepared according to the formula Ba0.95Sr0.05Ti1-ySnyO3. The solid-state reaction method enhanced by a high-efficiency metal ball mill was used in the preparation process. The quantitative and qualitative analysis of the XRD patterns confirmed the crystallization of the samples y = 0.00, 0.05 in the tetragonal crystal system and the presence of the tetragonal and cubic crystal systems together in the samples y = 0.10, 0.14. Formation of BaSnO3 impurities in very low percentages in the doped samples. Their prevalence increases with increasing tin content, reaching 8.7% at the ratio y = 0.14. SEM images of the ceramic samples showed the formation of nano-ceramics with a high degree of condensation at the doping ratio y = 0.05. The dielectric analyses showed high thermal stability in the dielectric properties of the ceramic samples y = 0.05, 0.10, which was shown by the flatness of the dielectric constant curve over the entire temperature range studied, where this stability is attributed to the structure of the nano-grains that resist the ferroelectric-paraelectric phase transition. Furthermore, the dielectric properties were interpreted by accurately linking the dielectric measurements with the nano-structural and polar properties. [ABSTRACT FROM AUTHOR]

To investigate the impact of PO43− anionic groups, the trivalent europium ion‐doped calcium molybdate (CaMoO3‐PO4:xEu3+, where x = 0.5, 1.0, 1.5, 2.0, and 2.5 mol%) phosphors were synthesized using the solid‐state reaction method. The detailed study of the phosphor materials was carried out by X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM), Fourier transform infrared spectroscopy (FT‐IR), X‐ray photoelectron spectroscopy (XPS), optical diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. The XRD results indicate that the substitution of PO43− anion and Eu3+ dopant ion did not affect the crystal structures of the CaMoO4 phosphors. Ultraviolet–visible (UV–vis) absorption analysis revealed the change of absorption edge of both un‐doped and Eu3+‐doped CaMoO4‐PO4 phosphors. Under the 394 nm UV‐excitation, the recorded PL spectra showed an intense peak at 615 nm corresponding to the Eu3+: 5D0 → 7F2 transition. The results of the Commission Internationale de l'Eclairage (CIE) diagram reported that the color of the emissions lies in the red color zone and there is no change in the CIE coordinates of the overall emission for Eu3+‐doped CaMoO4‐PO4 as Eu concentration changes. Thus, these observations led to finding the best red components for white light‐emitting diode applications. [ABSTRACT FROM AUTHOR]

The utilization of phosphors in lighting and display applications has garnered significant attention due to their unique luminescent properties and versatile crystal structures. This review article comprehensively examines recent advances in the synthesis, characterization, and applications of nitride and sulfide phosphors. This article addresses various phosphor crystal structures, including perovskite, garnet, nitride sulfide, fabrications strategies, and their impact on the optical and electronic properties. Furthermore, the review highlights the role of doping and activator ions in tailoring the emission characteristics of nitride and sulfide phosphors, enabling precise control over color rendering and efficiency. Additionally, the article also discusses emerging trends in phosphor technology, such as the development of novel synthesis methods and the integration of phosphors into next-generation lighting and display devices. The basic properties of phosphor materials like CRI, CIE chromaticity coordinates, quantum efficiencies are well discussed. Overall, this article provides valuable insights into the current state of research and future directions in the field of phosphors offering potential avenues for further advancements in lighting and display technologies. [ABSTRACT FROM AUTHOR]

(Cu,Te) co-doped CoSb 3 -based thermoelectric compounds Cu 0.3 Co 4 Sb 12-x Te x were synthesized rapidly by solid-state reaction method with the sintering temperature∼923 K and holding time ∼20 min. XRD analysis showed that the prepared samples Cu 0.3 Co 4 Sb 12-x Te x were single-phase skutterudite structure in the range of x < 0.7 %. SEM and EDS analyses show that the sample grains are fine with an average diameter of micro-nanometer and the sample contains many micro-pores inside and the grains have a relatively uniform distribution of elements. The lattice thermal conductivity at high temperature of Cu 0.3 Co 4 Sb 12-x Te x (x = 0,0.3,0.5, 0.7,0.9) significantly reduced by ∼50 % when compared to the samples at room temperature due to enhanced scattering of fine grains, micro porosity and grain boundary. The maximum power factor ∼2824 μWm−1K−2 was obtained for Cu 0.3 Co 4 Sb 11.5 Te 0.5 at 769 K and a maximum ZT value of ∼0.83 at 623 K are obtained from (Cu,Te) co-doped CoSb 3 material. [ABSTRACT FROM AUTHOR]

The variation of calcium phosphate formation rate on calcium titanate surfaces synthesized via sol-gel (CTSol) and solid-state reaction (CTS-S) at 600 °C for 10 h, were investigated using DSC, FTIR, XRD, DLS-Zeta potential, FESEM-EDS, BET, and ICP-OES, focusing on the relationship between surface morphology and calcium phosphate formation ability. Both powders had meso-porosities with a mean pore diameter of 45 and 54 nm, respectively. While CTSol particles had a diameter of about 100–250 nm, CTS-S had nanosized particles (35–40 nm) with the configuration of parent P25 TiO2. CTS-S had a higher specific surface area (26.14 m2. g−1), pore volume (0.36 cm3.g−1), and pore size (D = 54.51 nm) than CTSol (11.09 m2. g−1, 0.12 cm3.g−1, D = 44.97 nm). By submerging disk-shaped samples in SBF solution, their bioactivity was evaluated for up to 14 days. Both samples formed calcium phosphate at similar rates. Despite having a smaller surface area, CTSol makes up for it with a higher rate of Ca2+ dissolution. Whereas the calcium phosphate initial particles on the surface of CTS-S were spherical, the needle-like features on the surface of CTSol were created by immersion in SBF. Highlights: Two distinct processes were used to create calcium titanate. Two powders represented similar morphologies but different properties. The rate of Calcium Phosphate formation was approximately the same. Various morphologies were observed for the primary nuclei. The MTT evaluation indicated adequate cytocompatibility for powders. [ABSTRACT FROM AUTHOR]

Multiphase design is a promising approach to achieve superior ablation resistance of multicomponent ultra-high temperature ceramic, while understanding the ablation mechanism is the foundation. Here, through investigating a three-phase multicomponent ceramic consisting of Hf-rich carbide, Nb-rich carbide, and Zr-rich silicide phases, we report a newly discovered solid-state reaction process among multiphase multicomponent ceramic during ablation. It was found that this solid-state reaction occurred in the matrix/oxide scale interface region. In this process, metal cations are counter-diffused between the multicomponent phases, thereby resulting in their composition evolution, which allows the multicomponent phases to exist stably under a higher oxygen partial pressure, leading to the improvement of thermodynamic stability of three-phase multicomponent ceramic. Additionally, this solid-state reaction process appears synergistic with the preferential oxidation behavior among the oxide scale in enhancing the ablation performance. [ABSTRACT FROM AUTHOR]

Recently, there has been a growing interest in skutterudite (SKD) compounds containing electronegative elements such as Br, Cl, S, Se, and Te, owing to their increased diversity and the versatility of filler atoms. This study focused on the thermoelectric performance of a series of (Ni, Te) co-doped SKDs filled with the electronegative element S, denoted as SxNi0.4Co3.6Sb11.2Te0.8 (x = 0, 0.1, 0.2, and 0.3). These compounds were prepared using a combination of a solid-state reaction and spark plasma sintering techniques. The results showed that (Ni, Te) co-doping introduced excess electrons in the SKD lattice, while the incorporation of the element S into the SKD voids optimized carrier concentration. This led to a considerable increase in the absolute Seebeck coefficient to 110.6 μV K−1 at ambient temperatures. The presence of S fillers induced phonon resonance scattering and point scattering, which reduced lattice thermal conductivity and ultimately improved the thermoelectric figure of merit zT, which reached 0.93 for S0.3Ni0.4Co3.6Sb11.2Te0.8 at 823 K. [ABSTRACT FROM AUTHOR]

The preparation of a new series of luminescent one dimensional coordination polymers based on the association of a photoactive tetrametallic metallacycle Cu(I) precursor with pyridyl‐caped ditopic linkers is reported. In spite of related molecular architectures, these coordination polymers present upon Ultraviolet visible light photoexcitation markedly contrasted solid‐state luminescence behaviors including eye‐perceived colors of the emitted light spanning all over the visible spectrum. Solid‐state temperature‐dependent photophysical measurements and Time‐dependent density‐functional theory calculations have been conducted to identify the relaxation pathways lying in these assemblies. Very importantly, thermal stability studies at high temperature for all these derivatives reveal an irreversible post‐synthetic solid‐state transition that impacts dramatically the photophysical properties of these newly obtained phases, highlighting an innovative family of stimuli‐sensitive materials that can witness the exceeding of critical temperatures in their environment. [ABSTRACT FROM AUTHOR]

Synthesis and characterization of a Dy3+-activated calcium yttrium oxide (CaY2O4) phosphor are reported. The CaY2O4:Dy3+ (1.5 mol%) phosphor is synthesized using a modified solid-state reaction technique for calcination and sintering. The cubic structure is revealed by the X-ray diffraction technique. The morphology and particle size distribution of the prepared phosphor are investigated by the FEGSEM technique. The chemical bonds and functional group analysis are confirmed by the FTIR. A photoluminescence analysis of the CaY2O4:Dy3+ phosphor shows dual excitation wavelengths at 285 and 348 nm, especially in the ultraviolet region. At 383 nm, three distinct emission peaks are found at the wavelengths 238, 485, and 571 nm. The spectroscopic parameters are calculated using the CIE chromaticity coordinates. The CIE coordinates of the Dysprosium ion-activated CaY2O4 phosphor (1.5 mol%) show an emission near the white light region of the chromaticity diagram, suggesting that it is suitable for W-LED applications. [ABSTRACT FROM AUTHOR]

Abstract Geopolymer matrix composites (GMCs) are actively being developed for high‐temperature applications. In this work, we investigated different composite preparation parameters, such as the elaboration conditions (time, temperature and pressure) and composite dimensions (number of folds and surface area). In addition, we studied the effect of alkali cations (NaK or K), on metakaolin based geopolymer matrix composition, and textile type (N312, N610) of the composites on fiber–matrix interactions in high‐temperature geopolymer composites and their flexural behavior. The process we ultimately selected was as follows: an 8.5‐fold composite of surface area 100 cm2 was pressed for 2 h at 120°C. After thermal treatment at 1150°C, composites containing the N312 textile with B2O3 showed greater heterogeneity, viscous flow and lower flexural strength (7 MPa) due to fiber–matrix interactions. In contrast, above 1150°C, composites with the N610 textile had no fiber–matrix interactions and showed greater flexural strength (51 MPa). The specific flexural strength correlated well with the overmodifying element ratio based on the composite composition. In fact, the presence of viscous flow suggested that boron and some aluminum atoms could act as network modifiers. Thus, the two ratios were nSigeo+nAlgeonMgeo or nSigeo+N312+nAlgeo×0.5+nAlN312nMgeo+nBN312+nAlgeo×0.5 depending on the presence of viscous flow.

In this study, the influence of different additives on a geopolymer matrix composite (GMC) was explored as an alternative to a ceramic matrix composite (CMC) for thermostructural applications. Different GMCs using an N610 textile (10 × 10 cm2) and various additives (SrCO3, BaCO3, BaSO4, MgO and Al2O3 and mullite-rich powder) were cured under 6 MPa at 120 °C for 2 h. The mechanical, microstructural and structural data of the composites were compared with those of the geopolymer matrix after thermal treatment at 1150 °C. The results showed that the addition of alkali-earth barium carbonate or sulfate to the geopolymer matrix facilitated the formation of alkali-earth aluminosilicate crystalline phases and a higher viscous flow apparition temperature (990 °C), which did not enhance its mechanical properties (50 MPa) due to poor impregnation of the textile. Refractory additives such as MgO and Al2O3 in the geopolymer matrix support fiber impregnation with a low-viscous-flow apparition temperature (865 °C) and the formation of crystalline phases such as forsterite, spinel and sapphirine, which act as reinforcements, allowing a flexural strength up to 80 MPa. The addition of a refractory compound, such as mullite, leads to better embedding of fibers and a flexural strength reaching 100 MPa. To conclude, mixing the geopolymer matrix with refractory compounds results in a successful thermo-structural geopolymer composite.

Magnetic garnets, a diverse group of magnetic insulating materials, have been the subject of extensive research for decades, owing to their versatility and potential for a wide range of applications. In this study, we synthesized Bismuth-Substituted Yttrium Iron Garnet (BiY2Fe5O12: BiYIG) using the solid-state reaction method to explore its structural, optical, and dielectric characteristics. X-ray diffraction analysis revealed the attainment of a pure cubic garnet phase in BiYIG, with a lattice parameter of 12.444 Å. Using UV–visible spectroscopy, we determined that the optical band gap of BiYIG is 2.2 eV, indicating n-type semiconductor behavior. We conducted a thorough investigation of the dielectric properties, examining capacitance, dielectric constant, dielectric loss, conductivity, impedance, and modulus, as functions of frequency and temperature. The impedance results revealed that the dielectric relaxation at room temperature was dominated by a Debye-type process, with a shift to a non-Debye-type process becoming apparent as temperature increased. Comprehensive analysis sheds light on the material's transport phenomena and optical attributes, offering insights into the potential of BiYIG for applications in magneto-dielectric and magneto-optical domains, given its high dielectric constant with low dielectric loss, and promising optical properties. These findings position BiYIG as a versatile material and underscore its suitability for advanced applications in future technological developments.

Abstract In this study, entanglement of composition, additive and/or sintering conditions and their effects on magnetic properties of soft ferrites, nickel zinc spinel ferrites (Ni1−xZnxFe2O4, x = 0.65 and 0.70) which were prepared via conventional solid-state reaction method investigated. Also an equiponderant calcined mixture of Bi2O3, CaO, CeO2, SiO2, Al2O3, Y2O3 and nanotitania was mixed thoroughly and used as a multi-compound calcined additive (MCCA). Calcined ferrite powders were crushed, dry and wet milled, dried, mixed with different amounts of MCCA (0.0, 0.5, 1.0, 1.5 and 2.0 wt%), formed in toroidal shapes and finally sintered at different temperatures, from 1150 up to 1360 °C for 3 h. X-ray diffraction assessment confirmed formation of the single phase cubic spinel structures. Initial permeability and Q-factor spectra of the toroids were obtained from 0.1 to 1000 kHz, using an LCR meter. The results show that initial permeability of each sample has a maximum and addition of MCCA to the ferrites leads to a marvelous increase in permeabilities. Additionally, MCCA decreases the optimum sintering temperature too. The optimum amounts of additive were 1.0 and 0.5 wt% for the x = 0.65 (μ′ = 492, Ts = 1280 °C) and x = 0.70 (μ′ = 478, Ts = 1320 °C), respectively. Permeability spectra illustrate that utility zone of the Ni0.35Zn0.65Fe2O4 and Ni0.3Zn0.7Fe2O4 are both less than 100 and 10 kHz, respectively. The results represent that there is a strong entanglement between composition, additive and/or sintering conditions. It can be concluded the MCCA added Ni0.35Zn0.65Fe2O4, is suitable for application in the switching power supplies.

This study presents a comprehensive investigation into the synthesis, structural-spectroscopic characterization, and optical properties analysis of Sm3-activated NaZnPO 4 phosphors with varied Sm3+-doping percentiles, aimed at developing tunable luminescent materials for white-light-emitting diode (WLED) applications. The polycrystalline samples NaZn (1-x) Sm x 3+ PO 4 (x = 0.00, 0.05, 0.10 and 0.15) phosphors were synthesized via a solid-state reaction method. X-ray diffraction data analysis confirms single phase monoclinic lattice with space group P 1 21/c 1 for all compositions. The Rietveld procedure also confirms the single phase and monoclinic structure of synthesized phosphors. Fourier-transform infrared) spectroscopy confirms compositional homogeneity. FE-SEM micrographs show irregularly stacked microstructures and morphology for all compositions irrespective of Sm3+ doping percentage. While EDS and Elemental mapping confirm uniform incorporation of Sm3+ ions in phosphors lattice. Diffuse Reflectance Spectra studies show Sm3+ doping resulted in redshift and band gap narrowing. In Photoluminescence spectroscopies, excitation and emission spectra reveal that distinctive photoluminescence spectra with notable emission peaks at 402 nm (6H 5/2 → 4F 5/2) and 599 nm (4G 5/2 → 6H 5/2). CIE chromaticity coordinates demonstrated varied color purity and coordinates for different doping levels, with promising orange-red emissions and increased luminosity. The observed optical properties suggest the potential suitability of Sm3+-activated NaZnPO 4 phosphors as promising candidates for enhancing WLED efficiency and color quality. [ABSTRACT FROM AUTHOR]

To improve the luminescent efficiency of and to design the color spectrum of phosphors, the comprehensive understanding of the correlation between physical parameters and luminescent properties is imperative, necessitating systematic experimental studies. However, unintentional variations across individually prepared samples impede the thorough investigation of the correlation. In this study, we investigate the possible sources of unintentional variation in the photoluminescence properties of phosphors during sample preparation using a solid-state reaction, explicitly focusing on the ball milling process. Based on the quantitative features of the photoluminescent properties and their associated statistical errors, we explore the impact of unintentional variation alongside intended systematic variation, highlighting its potential to obscure meaningful trends. [ABSTRACT FROM AUTHOR]

Perovskite oxide La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 3 (LSGM) is an intermedium-temperature solid oxide cell electrolyte material with extraordinary oxygen-ion conductivity. However, the manufacturing procedures of LSGM discs are complex involving multiple steps of powder preparation, forming, and sintering at high temperatures. Herein, thin LSGM electrolyte discs are prepared by coupling of tape casting and in situ solid-state reaction using oxides/carbonates as the feedstock. A pure-phase LSGM electrolyte disc with uniform elemental distribution is obtained by sintering at 1450 °C, and it possesses an ionic conductivity of 0.105 S cm 1 at 800 °C, a thermal expansion coefficient of 12.2 × 10 6 K 1, and a bending strength of 156 MPa A 170 µm thick LSGM electrolyte-supported single cell delivers a peak power density of 0.96 W cm 2 at 800 °C and an electrolysis current density of 1.82 A cm 2 at 1.5 V with no noticeable degradation for 200 h. The findings of this research provide a cost-effective approach for manufacturing the LSGM electrolytes of efficient and durable solid oxide cells. • Thin LSGM discs are prepared by coupling of tape casting and in situ solid-state reaction. • Pure-phase LSGM discs are produced with favourable physical properties. • A LSGM-supported single cell exhibits outstanding output performance and durability. [ABSTRACT FROM AUTHOR]

We report the synthesis, characterizations, and hydrogen gas sensing of pure and silver (Ag)-doped bismuth sulfide (Bi2S3) nanobelts. The economical synthesis of Bi2S3 was carried out by the sulfurization of bismuth oxide (Bi2O3) using conventional solid-state reaction method. X-ray diffraction and scanning electron microscopy confirmed the synthesis of pure and silver-doped Bi2S3 nanobelts. Hydrogen gas sensing was studied at room temperature through current–voltage (I–V) characteristics. The percentage response of pure Bi2S3 nanobelts was 4.10%, whereas 2.5% silver-doped Bi2S3 showed a response of 24.01% at 26.66 kPa of H2 pressure. Response and recovery times were also analyzed from the dynamic response curves. Pure Bi2S3 nanobelts showed a response time of 8 s and recovery time of 20.4 s, whereas 2.5% silver-doped Bi2S3 nanobelts showed a response time of 6 s and recovery time of 15.2 s. The silver doping improved the reproducibility, selectivity, and stability of the sensor. [ABSTRACT FROM AUTHOR]

The ceramic compound CuFe2O4 was synthesised via conventional high-temperature solid-state reaction route. The structural study of the compound was done using X-ray diffraction technique. The preliminary structural study was performed using POWD software and a tetragonal structure was suggested. The Rietveld refinement of XRD (X-ray Diffraction) data was carried out using FullProf software and the refined lattice parameters were obtained as a = 5.80030 Å and c = 8.69400 Å with high tetragonality ratio. The crystallite size and lattice strain were calculated using Williamson–Hall (W-H) plot. The temperature and frequency dependent electrical properties of this compound are analysed using complex impedance technique. The impedance and modulus study of the compound showed the contribution of intra-grain effect to the overall electrical response. The studied ceramic possessed a non-Debye-type relaxation mechanism. The bulk resistance decreased with the increase in temperature, thus showing negative temperature coefficient of resistance behaviour. Modulus and conductivity study showed the evidence of conduction via hopping mechanism inside the material. Frequency-dependent AC conductivity followed Jonscher's universal power law. The Arrhenius equation was fitted with the temperature-dependent AC conductivity at different frequencies, and activation energies were determined to understand the charge species involved in the conduction mechanism. [ABSTRACT FROM AUTHOR]

Over the past three decades, bioresorbable ceramics such as beta-tricalcium phosphate (β-TCP)-based porous scaffolds have been extensively studied. β-TCP-based scaffolds or cements for bone tissue applications have proved to be an outstanding alternative to repair and regenerate bone tissue defects caused by trauma or injury. In this study, an investigation on submicron β-TCP powders derived from prawn shell (Fenneropenaeus indicus, a source of marine biowaste) via solid-state reaction approach was carried out, which has calcite (CaCO3) in its exoskeleton (nonedible). The prawn shell-derived β-TCP can be prepared conventionally with dicalcium phosphate (CaHPO4) at different temperatures 900, 1000, 1100, and 1200 °C. The EDX spectra detect the Ca:P ratio of 1.5 confirming the formation of pure β-TCP at 1100 °C, which is in complete agreement with theoretical ratio. X-ray diffraction pattern revealed the phase-pure crystalline rhombohedral crystal structure of β-TCP with an average crystallite size of ~ 25.8 nm, prepared at 1100 °C. The field emission scanning electron microscopy images showed a homogeneous distribution of β-TCP powders with an average grain size of 3.07 µm at 1100 °C. Furthermore, Raman spectroscopy and Fourier transform infrared spectroscopy confirm the characteristics peaks of β-TCP. Differential scanning calorimetry and thermogravimetric analysis are performed to study the thermal behavior of the initial precursors mixture to synthesize β-TCP. β-TCP scaffolds sintered at 1100 °C exhibited compressive strength of ~ 6.2 MPa, for which Ca/P ratio is 1.51. Biodegradation study conducted on β-TCP scaffolds sintered at 1100 °C has shown slow degradation rate up to 5 days. Therefore, the prawn shell-derived β-TCP has physical and morphological properties which projects it as a promising implantable biomaterial for synthetic bone graft substitutes. [ABSTRACT FROM AUTHOR]

Zinc sulfide (ZnS) is one of the leading semiconductors for optoelectronic device applications. Here, we focused on synthesizing the undoped and transition metal (Cu)-doped ZnS (Zn 1 - x Cu x S) nanoparticles at different copper concentrations (x = 0, 0.03, 0.05, 0.07) using solid-state reaction. The synthesized Zn 1 - x Cu x S nanoparticles were subjected to different characterizations such as XRD, FE-SEM, EDS, UV–visible spectroscopy, PL, and two probe methods to study their structural, morphological, elemental, optical, and electrical properties. The XRD profile revealed that the prepared nanoparticles were in cubic structure with predominant orientation along (1 1 1) plane. The EDAX spectra confirmed the presence of host and dopant elements such as Zn, S, and Cu without any impurity elements. The formation of spherical-shaped clusters was confirmed by FE-SEM images. Using absorption spectra, the band gaps were calculated. Novel luminescence features, i.e., blue, green, and orange-red emission peaks, were observed in the photoluminescence spectra. Electrical properties were studied using two probe method (Keysight B2900 source meter). [ABSTRACT FROM AUTHOR]

Indium tin oxide (ITO) ceramics with different SnO2 contents were fabricated using the conventional solid-state reaction. The phase structure, microstructure, electrical conductivity, heating, and mechanical properties were investigated in detail. The results showed that pure ITO ceramics with high relative density were obtained successfully. The ITO ceramics were cut into regular rectangles to serve as electrical heaters. Additionally, their saturation temperatures and thermal response times were tested at different voltages. The results showed that ITO ceramics with 10% SnO2 had the fastest thermal response rate and reached a saturation temperature of 376∘C at 1.5 V voltage, the highest temperature reported in the literature for In2O3 ceramics. Moreover, In2O3 with 10% SnO2 showed good mechanical properties. Hence, ITO ceramics, as electrical heaters with low driving voltage and high response speed, are expected to have potential heating applications such as domestic heating and industrial production. [ABSTRACT FROM AUTHOR]

It is known that high‐temperature phase (olivine structure) of NaMgPO4:Eu2+ (NMP:Eu2+) is a precious oxide phosphor suitable for LED devices, emitting red at 625 nm under blue excitation. However, mainly due to the stable glaserite structure in the wide range of low temperature, pure olivine‐phase NMP:Eu2+ is obtained only by using melt‐quenching and arc‐imaging furnace so far, which is inconvenient for the purpose of mass‐production or industry. Generally, a traditional solid‐state method is simpler and pollution‐free, which is more favorable in phosphor‐industry. Here, it is found that when quite small amount of Zn2+ is substituted for NMP:Eu2+ in solid‐state method, the purity of olivine phase is much improved and the luminescence intensity is significantly improved. For the Na(Mg,Zn)PO4:Eu2+ having new composition, crystal structure, optical properties, and color properties are investigated. The phase transition temperature before and after doping with Zn2+ are calculated by combining TG/DSC experimental measurements and first‐principles calculations. In addition, other characteristics related to the phosphor, such as structure, morphology, luminescence lifetime, thermal quenching properties, and quantum efficiency, are also studied in detail. Finally, it is demonstrated that this phosphor can be utilized in various applications through the manufacturing of LED devices, fluorescent pigments, and plant growth. [ABSTRACT FROM AUTHOR]