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Ceramics
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Composite Nanopowders: Synthesis and Applications
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Composite Nanopowders: Synthesis and Applications

A special issue of Ceramics (ISSN 2571-6131).

Deadline for manuscript submissions: closed (30 September 2023) | Viewed by 26070

Special Issue Editor

Dr. Sergey Mjakin

E-Mail Website
Guest Editor
Saint-Petersburg State Institute of Technology (Technical University), 26 Moskovsky prospect, 190013 St. Petersburg, Russia
Interests: surfaces and interfaces; composites; ceramics; electrochromic materials

Special Issue Information

Dear Colleagues,

The Special Issue "Composite Nanopowders: Synthesis and Applications” will involve regular research articles, reviews and short communications devoted to the development of synthetic approaches to obtaining various nanosized/submicron ceramic materials with the target performances (particularly including specific properties adjustable by the variation of the synthesis conditions), their characterization (in respect of particle size distribution, controllable agglomeration, surface/interface and textural characteristics, specific adsorption, electric, magnetic properties, biocompatibility, etc.), modeling/simulation and applications (manufacturing of products with the target properties by sintering, additive technologies and other methods, incorporation into special composites, development of materials with a “core–shell” structure, biomedical applications such as targeted drug delivery and controllable/prolonged release, catalysis, including photocatalysts and carriers for catalysts, etc.).  

Dr. Sergey Mjakin
Guest Editor

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Keywords

  • ceramics
  • nanoparticles
  • surface and interface properties
  • carriers
  • composites
  • “core-shell” structure
  • catalysis and photocatalysis
  • targeted drug delivery

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Published Papers (13 papers)

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Research

12 pages, 3695 KiB  
Article
One-Step Microwave Synthesis of New Hybrid Phosphor (CSSC) for White Light-Emitting Diodes
by Maxim Sychov, Mariia Keskinova, Andrey Dolgin, Igor Turkin, Kazuhiko Hara and Hiroko Kominami
Ceramics 2023, 6(4), 2086-2097; https://doi.org/10.3390/ceramics6040128 - 19 Oct 2023
Viewed by 1564
Abstract
The possibility of synthesizing a new hybrid phosphor CSSC (mixture of 0.5 CaSrSiO4:Eu2+: 0.29 Ca6Sr4Si6O21Cl2:Eu2+: 0.21 Ca10Si6O21Cl2:Eu2+) [...] Read more.
The possibility of synthesizing a new hybrid phosphor CSSC (mixture of 0.5 CaSrSiO4:Eu2+: 0.29 Ca6Sr4Si6O21Cl2:Eu2+: 0.21 Ca10Si6O21Cl2:Eu2+) using a one-step microwave synthesis method is demonstrated. The concentrations of europium and calcium in the synthesized phosphors were optimized at 1 and 10 mol. %, respectively, to achieve maximum brightness and color rendering index. The optimal conditions for the synthesis of phosphors in a microwave furnace were determined as 750 °C for 10 min. The resulting phosphor exhibited a wide luminescence spectrum that covered the entire visible region, resulting in a high color rendering index and a warm white luminescence when used as a light source. It is shown that the sol–gel method for preparing the charge mixture for the new phosphor allows for a 35% higher luminescence brightness compared to the solid-phase method, due to a more uniform distribution of the activator. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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14 pages, 4142 KiB  
Article
Microstructure, Mechanical and Thermal Properties of ZTA/Al2TiO5 Ceramic Composites
by A. M. Hassan, Hamada Elsayed, M. Awaad, A. M. Saleh and S. M. Naga
Ceramics 2023, 6(4), 1977-1990; https://doi.org/10.3390/ceramics6040121 - 4 Oct 2023
Viewed by 2450
Abstract
Zirconia-toughened alumina (ZTA)/Al2TiO5 composites were prepared via a sol–gel route. The prepared samples were uniaxially pressed and pressurelessly sintered at 1650–1700 °C for 1 h. The microstructure, densification, and X-ray diffraction patterns of the sintered ZTA/Al2TiO5 composites [...] Read more.
Zirconia-toughened alumina (ZTA)/Al2TiO5 composites were prepared via a sol–gel route. The prepared samples were uniaxially pressed and pressurelessly sintered at 1650–1700 °C for 1 h. The microstructure, densification, and X-ray diffraction patterns of the sintered ZTA/Al2TiO5 composites were investigated, and their mechanical properties, thermal coefficient, and shock resistance were characterized. The addition of Al2TiO5 hindered the grain growth of the alumina particles and enhanced the relative density, Vickers hardness, and bending strength of the composites compared with pure ZTA samples. The fracture toughness was improved by 19% upon the addition of 40 wt% Al2TiO5. Moreover, increasing the Al2TiO5 content resulted in an improvement in the thermal shock resistance. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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14 pages, 3828 KiB  
Article
Effect of Diamond Phase Dispersion on the Properties of Diamond-SiC-Si Composites
by Sergey P. Bogdanov, Andrey S. Dolgin, Sergey N. Perevislov, Nikolay A. Khristyuk and Maxim M. Sychov
Ceramics 2023, 6(3), 1632-1645; https://doi.org/10.3390/ceramics6030100 - 28 Jul 2023
Viewed by 1461
Abstract
The research aimed at the composition optimization for diamond-SiC-Si composites. The effect of a porous diamond workpiece was studied on the properties (porosity, density, modulus of elasticity, phase composition) of the product of its siliconization with molten silicon. The lowest porosity and highest [...] Read more.
The research aimed at the composition optimization for diamond-SiC-Si composites. The effect of a porous diamond workpiece was studied on the properties (porosity, density, modulus of elasticity, phase composition) of the product of its siliconization with molten silicon. The lowest porosity and highest modulus of elasticity were observed in the case of using mixed matrices with the maximum size of diamond grains of 250/200 μm for siliconization. The best results in terms of the sound speed (16,600 m/s) and elasticity modulus (860 GPa) were achieved by microwave processing of a composite containing detonation nanodiamonds. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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9 pages, 1534 KiB  
Article
Phase Composition and Magnetic Properties of Nanoparticles with Magnetite–Maghemite Structure
by Sergey I. Andronenko, Anton M. Nikolaev, Stanislav M. Suharzhevsky, Alexander A. Sinelnikov, Anastasia S. Kovalenko, Alexandra G. Ivanova and Olga A. Shilova
Ceramics 2023, 6(3), 1623-1631; https://doi.org/10.3390/ceramics6030099 - 18 Jul 2023
Cited by 4 | Viewed by 1872
Abstract
Precipitation of nanopowders with mixed magnetite–maghemite composition was carried out under different conditions and with different separation techniques. The exact character of interactions of different iron oxide phases in the nanopowder was the main object of interest. The obtained nanopowders have spherical particles [...] Read more.
Precipitation of nanopowders with mixed magnetite–maghemite composition was carried out under different conditions and with different separation techniques. The exact character of interactions of different iron oxide phases in the nanopowder was the main object of interest. The obtained nanopowders have spherical particles about 10–20 nm in size. Electron paramagnetic resonance (EPR) study showed that iron ions incorporate fully into magnetite and maghemite structures. The shape of the EPR line points out that single homogenous solid solutions were formed during synthesis. In the studied solid solutions, different ratios of vacancies and Fe2+/Fe3+ ratios were observed but in spite of different synthesis techniques in both cases, there were no additional diamagnetic structural phases presented. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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17 pages, 5032 KiB  
Article
Comparative Study of Physicochemical Properties of Finely Dispersed Powders and Ceramics in the Systems CeO2–Sm2O3 and CeO2–Nd2O3 as Electrolyte Materials for Medium Temperature Fuel Cells
by Marina V. Kalinina, Daria A. Dyuskina, Sergey V. Mjakin, Irina Yu. Kruchinina and Olga A. Shilova
Ceramics 2023, 6(2), 1210-1226; https://doi.org/10.3390/ceramics6020073 - 4 Jun 2023
Cited by 1 | Viewed by 1470
Abstract
Finely dispersed (CeO2)1−x(Sm2O3)x (x = 0.05, 0.10, 0.20) and (CeO2)1−x(Nd2O3)x (x = 0.05, 0.10, 0.15, 0.20, 0.25) powders were synthesized via liquid-phase techniques based on [...] Read more.
Finely dispersed (CeO2)1−x(Sm2O3)x (x = 0.05, 0.10, 0.20) and (CeO2)1−x(Nd2O3)x (x = 0.05, 0.10, 0.15, 0.20, 0.25) powders were synthesized via liquid-phase techniques based on the co-precipitation of hydroxides and were used to obtain ceramic materials comprising fluorite-like solid solutions with CSR in the range 69–88 nm (upon annealing at 1300 °C) and open porosity in the range 0.6–6.2%. The physicochemical properties of the synthesized materials were comparatively characterized. In general, the prepared materials were found to possess a mixed type of electrical conductivity, but in the medium-temperature range, the ionic component was predominant (ion transfer numbers ti = 0.93–0.73 at 300–700 °C). The highest ionic conductivity was observed for CeO2-based samples containing 20 mol.% Sm2O3 (σ700°C = 3.3 × 10−2 S/cm) and 15 mol.% Nd2O3 (σ700°C = 0.48 × 10−2 S/cm) was in the temperature range 500–700 °C. The physicochemical properties (density, open porosity, type and mechanism of electrical conductivity) of the obtained ceramic materials make them promising as solid oxide electrolytes for medium temperature fuel cells. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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13 pages, 2330 KiB  
Article
Effect of Synthetic Approaches and Sintering Additives upon Physicochemical and Electrophysical Properties of Solid Solutions in the System (CeO2)1−x(Nd2O3)x for Fuel Cell Electrolytes
by Marina V. Kalinina, Daria A. Dyuskina, Irina G. Polyakova, Sergey V. Mjakin and Irina Yu. Kruchinina
Ceramics 2023, 6(2), 1100-1112; https://doi.org/10.3390/ceramics6020065 - 11 May 2023
Viewed by 1526
Abstract
Finely dispersed (CeO2)1−x(Nd2O3)x (x = 0.05, 0.10, 0.15, 0.20, 0.25) powders are synthesized via liquid-phase techniques based on the co-precipitation of hydroxides and co-crystallization of nitrates. The prepared powders are used to obtain ceramic [...] Read more.
Finely dispersed (CeO2)1−x(Nd2O3)x (x = 0.05, 0.10, 0.15, 0.20, 0.25) powders are synthesized via liquid-phase techniques based on the co-precipitation of hydroxides and co-crystallization of nitrates. The prepared powders are used to obtain ceramic materials comprising fluorite-like solid solutions with the coherent scattering region (CSR) of about 88 nm (upon annealing at 1300 °C) and open porosity in the range of 1–15%. The effect of the synthesis procedure and sintering additives (SiO2, ZnO) on physicochemical and electrophysical properties of the resulting ceramics is studied. The prepared materials are found to possess a predominantly ionic type of electric conductivity with ion transfer numbers ti = 0.96–0.71 in the temperature range of 300–700 °C. The conductivity in solid solutions follows a vacancy mechanism with σ700 °C = 0.48 × 10−2 S/cm. Physicochemical properties (density, open porosity, type and mechanism of electrical conductivity) of the obtained ceramic materials make them promising as solid oxide electrolytes for medium temperature fuel cells. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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11 pages, 2592 KiB  
Article
Digital Characteristics of Microstructure of Diamond—Silicon Carbide Composites
by Andrey G. Chekuryaev, Maxim M. Sychov, Sergey N. Perevislov and Vladimir N. Ulanov
Ceramics 2023, 6(2), 1067-1077; https://doi.org/10.3390/ceramics6020063 - 1 May 2023
Cited by 1 | Viewed by 1812
Abstract
As an example of the implementation of digital materials science approaches based on statistical processing of electron micrographs with the analysis of fractal parameters, the digital characteristics of microstructure of diamond–silicon carbide ceramic composite material are calculated. The lacunarity parameter characterizing the non-uniform [...] Read more.
As an example of the implementation of digital materials science approaches based on statistical processing of electron micrographs with the analysis of fractal parameters, the digital characteristics of microstructure of diamond–silicon carbide ceramic composite material are calculated. The lacunarity parameter characterizing the non-uniform distribution of filler particles in the matrix is found. Based on lacunarity values calculated at different scales, scale invariance parameter characterizing the dependence of lacunarity on the scale is evaluated. Voronoi entropy characterizing the structure based on the quantity of information is also calculated and used to determine the average number of neighboring particles and average distance between them. For the composites with high mechanical properties, the number of nearest neighbors approaches six, indicating an almost closest packing. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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13 pages, 3411 KiB  
Article
Influence of the Preparation Method on the Physico-Chemical and Sorption Properties of Montmorillonite
by Olga Yu. Golubeva, Elena Yu. Brazovskaya and Yulia A. Alikina
Ceramics 2023, 6(2), 922-934; https://doi.org/10.3390/ceramics6020054 - 3 Apr 2023
Cited by 1 | Viewed by 1694
Abstract
Layered silicates with a montmorillonite structure are widely used in various fields related to adsorption, gas and water treatment, catalysis, cosmetology and medicine. Under conditions of directed hydrothermal synthesis, montmorillonites with the specified characteristics can be obtained. The influence of the preparation method [...] Read more.
Layered silicates with a montmorillonite structure are widely used in various fields related to adsorption, gas and water treatment, catalysis, cosmetology and medicine. Under conditions of directed hydrothermal synthesis, montmorillonites with the specified characteristics can be obtained. The influence of the preparation method for montmorillonites of two compositions (Mg3Si4O10(OH)2 H2O and Na1.5Al0.5Mg1.5Si4O10(OH)2 H2O) on their sorption properties, moisture absorption, porous textural characteristics and surface properties has been studied. The nature of the initial reagents, the pH of the reaction medium and the synthesis temperature were chosen as the variable synthesis parameters. It has been established that the synthesis conditions significantly affect the properties of montmorillonite, which, in turn, determines the possibilities of using the materials obtained in specific areas. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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10 pages, 1993 KiB  
Article
3D Printing of Ceramic Elements with Q-Surface Geometry for the Fabrication of Protective Barrier
by Semen V. Diachenko, Andrey S. Dolgin, Nikolai A. Khristyuk, Lev A. Lebedev, Lubov A. Nefedova, Sergey B. Pavlov, Kirill F. Merenkov, Vladimir I. Ivkov and Alla N. Dmitrieva
Ceramics 2023, 6(2), 912-921; https://doi.org/10.3390/ceramics6020053 - 3 Apr 2023
Cited by 3 | Viewed by 2423
Abstract
The work proposes the use of aluminum oxide-based ceramic objects with a TPMS-Q-surface geometry as elements of armor structures. The samples were produced using the SLA-DLP 3D printing method. The main properties of the sample were determined using physical-chemical analysis methods: apparent density [...] Read more.
The work proposes the use of aluminum oxide-based ceramic objects with a TPMS-Q-surface geometry as elements of armor structures. The samples were produced using the SLA-DLP 3D printing method. The main properties of the sample were determined using physical-chemical analysis methods: apparent density ρap = 3.6 g/cm3, open porosity Popn = 8.5%, microhardness Hµ = 15.3 GPa, water absorption W = 2.4%, elastic modulus E = 405 GPa. The Stiglich criterion M = 1.72 EPa2·m3/kg, and the Shevchenko criterion K = 0.8. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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12 pages, 2759 KiB  
Article
Ceramic ZnO-SnO2-Fe2O3 Powders and Coatings -Effective Photogenerators of Reactive Oxygen Species
by Larisa Khomutinnikova, Sergey Evstropiev, Igor Meshkovskii, Igor Bagrov and Valery Kiselev
Ceramics 2023, 6(2), 886-897; https://doi.org/10.3390/ceramics6020051 - 2 Apr 2023
Cited by 5 | Viewed by 2008
Abstract
Ceramic ZnO-SnO2-Fe2O3 powders and transparent coatings on glasses prepared using the non-isothermal polymer-salt method demonstrate a strong ability to generate chemically active oxygen species under UV and visible irradiation. Crystal structures and morphologies of these materials were studied [...] Read more.
Ceramic ZnO-SnO2-Fe2O3 powders and transparent coatings on glasses prepared using the non-isothermal polymer-salt method demonstrate a strong ability to generate chemically active oxygen species under UV and visible irradiation. Crystal structures and morphologies of these materials were studied using the XRD and the SEM analysis. It was found that there are significant differences in the crystal structure of ceramic powders and thin coatings. The powders consist of randomly oriented oxide nanocrystals of size ~47 nm. The strong orientation of the ZnO nanocrystals due to their interaction with the glass substrate is observed in the coating structure. Experimental data show that thin ceramic coatings are transparent (~90%) in the visible spectral range and the band gap of the ceramic material is 3.44 eV. The band gap value of this multi-component ceramic material is described sufficiently using Verlag’s law. Ceramic powders and coatings demonstrate the intensive photogeneration of reactive oxygen species, both in liquid and air. High photocatalytic activity of ZnO-SnO2-Fe2O3 ceramic coatings and powders was observed upon the oxidation of the diazo dye, Chicago Sky Blue. In the presence of transparent photocatalytic coating, the value of the constant rate of the dye photodecomposition was high (k = 0.056 min−1). It was found that, in spite of their short life time, photogenerated reactive oxygen species demonstrate the ability to decompose dye molecules located up to a distance of 0.5 mm from the surface of ceramic coating. Obtained experimental results suggest that the prepared ceramic materials are promising for different practical applications of the photocatalytic materials. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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23 pages, 13030 KiB  
Article
Powders Synthesized from Solutions of Calcium Chloride, Sodium Hydrogen Phosphate, and Sodium Sulfate for Bioceramics Production
by Tatiana V. Safronova, Alexander S. Khantimirov, Tatiana B. Shatalova, Yaroslav Y. Filippov, Irina V. Kolesnik and Alexander V. Knotko
Ceramics 2023, 6(1), 561-583; https://doi.org/10.3390/ceramics6010034 - 22 Feb 2023
Cited by 2 | Viewed by 2920
Abstract
Fine powders of brushite CaHPO4·2H2O, ardealite Ca(HPO4)x(SO4)1−x·2H2O (Ca(HPO4)0.5(SO4)0.5·2H2O), and calcium sulfate dihydrate CaSO4·2H2O—all containing sodium [...] Read more.
Fine powders of brushite CaHPO4·2H2O, ardealite Ca(HPO4)x(SO4)1−x·2H2O (Ca(HPO4)0.5(SO4)0.5·2H2O), and calcium sulfate dihydrate CaSO4·2H2O—all containing sodium chloride NaCl as a reaction by-product—were synthesized from 0.5 M aqueous solution of calcium chloride CaCl2, sodium hydrophosphate Na2HPO4 and/or sodium sulfate Na2SO4. Powder of ardealite Ca(HPO4)x(SO4)1−x·2H2O (Ca(HPO4)0.5(SO4)0.5·2H2O) was synthesized by precipitation from aqueous solution of calcium chloride CaCl2 and mixed-anionic solution simultaneously containing the hydrogen phosphate anion HPO42− (Na2HPO4) and sulfate anion SO42− (Na2SO4). Sodium chloride NaCl, presenting in compacts based on synthesized powders of brushite CaHPO4·2H2O, ardealite Ca(HPO4)x(SO4)1−x·2H2O (Ca(HPO4)0.5(SO4)0.5·2H2O) and calcium sulfate dihydrate CaSO4·2H2O, was responsible for both low-temperature melt formation and the creation of phase composition of ceramics. Heterophase interaction of components led to the resulting phase composition of the ceramic samples during heating, including the formation of chlorapatite Ca5(PO4)3Cl in powders of brushite and ardealite. The phase composition of the ceramics based on the powder of brushite CaHPO4·2H2O containing NaCl as a by-product after firing at 800–1000 °C included β-Ca2P2O7, and Ca5(PO4)3Cl. The phase composition of ceramics based on the powder of ardealite Ca(HPO4)x(SO4)1−x·2H2O (Ca(HPO4)0.5(SO4)0.5·2H2O) containing NaCl as a by-product after firing at 800 and 900 °C included β-Ca2P2O7, CaSO4, and Ca5(PO4)3Cl; after firing at 1000 °C, it includedCaSO4, Ca5(PO4)3Cl and Ca3(PO4)2/Ca10Na(PO4)7, and after firing at 1100 °C, it included CaSO4 and Ca5(PO4)3Cl. The phase composition of ceramics based on powder of calcium sulfate dihydrate CaSO4·2H2O containing NaCl as a by-product after firing at 800–1100 °C included CaSO4 as the predominant phase. The phase composition of all ceramic samples under investigation consisted of biocompatible crystalline phases with different abilities to biodegrade. For this reason, the created ceramics can be recommended for testing as materials for treatment of bone defects using regenerative medicine methods. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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12 pages, 2828 KiB  
Article
Solvothermal Synthesis of LaF3:Ce Nanoparticles for Use in Medicine: Luminescence, Morphology and Surface Properties
by Anastasiia Dorokhina, Ryoya Ishihara, Hiroko Kominami, Vadim Bakhmetyev, Maxim Sychov, Toru Aoki and Hisashi Morii
Ceramics 2023, 6(1), 492-503; https://doi.org/10.3390/ceramics6010028 - 7 Feb 2023
Cited by 4 | Viewed by 2046
Abstract
A series of LaF3:Ce3+ phosphors for application in photodynamic therapy are synthesized using a one-stage solvothermal synthesis. The synthesis conditions; type and quantity of stabilizer; concentration of activator providing the maximum intensity of UV- and X-ray-excited luminescence; lowest size; and [...] Read more.
A series of LaF3:Ce3+ phosphors for application in photodynamic therapy are synthesized using a one-stage solvothermal synthesis. The synthesis conditions; type and quantity of stabilizer; concentration of activator providing the maximum intensity of UV- and X-ray-excited luminescence; lowest size; and highest colloidal stability of the phosphor nanoparticles are found. As a result of this study, the following parameters are determined using cerium content 5% mol. ethanol as the reaction medium for the solvothermal synthesis and polyvinylpyrrolidone as the stabilizer at an optimized amount. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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13 pages, 3027 KiB  
Article
Structural and Luminescence Properties of (Gd1−xYx)2O3 Powders Doped with Nd3+ Ions for Temperature Measurements
by Vladimir Aseev, Anastasiia Babkina, Sergey Evstropiev, Natalia Kuzmenko, Irina Sevastianova, Denis Prokuratov and Mikhail Khodasevich
Ceramics 2022, 5(4), 1185-1197; https://doi.org/10.3390/ceramics5040084 - 3 Dec 2022
Cited by 1 | Viewed by 1674
Abstract
Rare earth activated powders are widely regarded as promising candidates for optical thermometry due to their unique photoluminescence characteristics. The paper presents the structural and luminescent properties of crystalline powders of gadolinium and yttrium oxides (Gd1−xYx)2O3 [...] Read more.
Rare earth activated powders are widely regarded as promising candidates for optical thermometry due to their unique photoluminescence characteristics. The paper presents the structural and luminescent properties of crystalline powders of gadolinium and yttrium oxides (Gd1−xYx)2O3, doped with Nd3+ ions, synthesized by the liquid polymer-salt method. The addition of polyvinylpyrrolidone increases the homogeneity of the mixture and ensures high adhesion of the resulting powders. Scanning electron microscopy shows that powders are μm-sized aggregates, which consist of particles with several tens of nanometers in size. A smooth shift of the diffraction peaks of the powders occurs when Gd is replaced by Y without additional peaks. The successive decrease in the lattice constant of the powders from 10.816 to 10.607 Å confirms the existence of continuous solid solutions in the system. The Stark sublevels of the 4F3/2 → 4I9/2 fluorescent band are shifted to 4 nm when Gd is replaced by Y since the strength of the local field has a stronger effect on the inner F-shell of Nd ions in the case of Y. For thermometry, we chose the ratio of the fluorescence intensities between the Stark sublevels 4F3/2(2) → 4I9/2(2) and 4F3/2(1) → 4I9/2(2). The best obtained sensitivity is 0.22% °C−1 for Nd-doped GdYO3 powder in the range of 10–70 °C. This value of temperature sensitivity, together with radiation and excitation lying in the biological window, opens the possibility of using Nd3+-doped (Gd1−xYx)2O3 powders for real-time thermal probing of under tissue luminescence with sub-degree resolution. Full article
(This article belongs to the Special Issue Composite Nanopowders: Synthesis and Applications)
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