scholarly journals Thin Films and Glass–Ceramic Composites of Huntite Borates Family: A Brief Review

Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 487
Author(s):  
Elena A. Volkova ◽  
Daniil A. Naprasnikov ◽  
Nikolay I. Leonyuk
Keyword(s):  
Rare Earth ◽  
Glass Ceramic ◽  
Optical Waveguides ◽  
Optical Glass ◽  
Ceramic Materials ◽  
Ceramic Composites ◽  
Epitaxial Layers ◽  
Waveguide Lasers ◽  
Laser Systems ◽  
Physical And Chemical

Rare-earth aluminum borates, RAl3(BO3)4 (where R = Y, Pr–Lu), are of great interest because of their attractive multifunctional properties, depending on their structure and composition. The combination of desirable physical and chemical characteristics makes them promising materials for lasers and nonlinear optics. Research focusing on RAl3(BO3)4 (RAB) compounds and their solids solutions has continued for more than five decades and has been reflected in numerous articles and several reviews. The last decade’s enhanced interest is being conducted towards epitaxial layers because of the availability of other possible applications, for instance, as scintillators, visible emitting phosphors or optical waveguides and waveguide lasers. On the other hand, the tendency of borate melts to form glasses makes them attractive for research of micro-crystallization processes in these systems and can be effortless towards finding relatively inexpensive optical glass–ceramic materials with similar composition as alternative components to laser systems. This article reviews the recent progress carried out hitherto on epitaxial layers and glass–ceramic composites of huntite-type rare-earth aluminum borates.

scholarly journals Properties of glasses in the system BaO–B2O3–SiO2–xAl2O3 (x=0; 5; 10 mol.%)

2021 ◽  
pp. 83-89
Author(s):  
Yu.S. Hordieiev ◽  
◽  
E.V. Karasik ◽  
А.A. Amelina ◽  
◽  
...  
Keyword(s):  
Chemical Composition ◽  
Glass Ceramic ◽  
Glass Formation ◽  
Linear Thermal Expansion ◽  
Chemical Properties ◽  
Ceramic Materials ◽  
Heat Resistant ◽  
Glass Ceramic Materials ◽  
Wide Range ◽  
Physical And Chemical

This article shows the prospect of the system BaO–Al2O3–B2O3–SiO2 as the basis of vitreous and glass ceramic materials, which are widely used in rocket production for high-temperature protection of heat resistant alloys, in the power industry for sealing solid oxide fuel cells, and in the production of heat resistant glass ceramic materials. We examined the conditions of glass formation and properties of glasses with the following content of components (mol.%): BaO 30–70, B2O3 10–50, SiO2 20–60, and Al2O3 0–10. We established experimentally that the physical and chemical properties of glass, depending on its chemical composition, vary within the following limits: coefficient of linear thermal expansion of (71–122)10–7 К–1; glass transition temperature of 500–6500С; dilatometric softening point of 540–6700С; and density of 3.20–4.21 g cm–3. The volume resistivity of the studied glasses is within 1011–1013 Ohmcm at the temperature of 1500С. Generalization of the dependences of glass properties on their chemical composition was carried out with the use of the additive equations, for which the partial contributions of oxides to the values of the corresponding properties were determined by experimental and statistical methods. The established patterns of influence of components and conditions of glass formation on the physical and chemical characteristics of glasses allows implementing the process of designing of a wide range of glass compositions with the complex of specified properties in order to solve the tasks of their practical use.

scholarly journals Thermochemical Preparation and Properties of Low-Cost Polylanthanide Manganite Materials of Ln(La, Ce, Nd, Pr)xCayMnO3-Type with Perovskite-Fluorite Structure

2020 ◽  
Vol 19 (6) ◽  
pp. 528-535
Author(s):  
V. A. Gorbunova ◽  
L. M. Sliapniova ◽  
A. V. Gorbunov
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Low Cost ◽  
Ceramic Materials ◽  
Fluorite Structure ◽  
Chemical Investigation ◽  
Physical And Chemical

A physical and chemical investigation of ceramic materials based on manganites of mixed rare earth elements  –

Glass-ceramic composites for high-power white-light-emitting diodes

2021 ◽  
Author(s):  
Alessandro Longato ◽  
Sebastiano Picco ◽  
Lorenzo Moro ◽  
Matteo Buffolo ◽  
Carlo De Santi ◽  
...  
Keyword(s):  
White Light ◽  
High Power ◽  
Glass Ceramic ◽  
Light Emitting Diodes ◽  
Ceramic Composites ◽  
Light Emitting ◽  
White Light Emitting Diodes

scholarly journals Towards Higher Electric Conductivity and Wider Phase Stability Range via Nanostructured Glass-Ceramics Processing

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1321
Author(s):  
Tomasz K. Pietrzak ◽  
Marek Wasiucionek ◽  
Jerzy E. Garbarczyk
Keyword(s):  
Glass Ceramic ◽  
Electronic Conductivity ◽  
Glass Ceramics ◽  
Temperature Stability ◽  
Ceramic Materials ◽  
Glassy Matrix ◽  
Oxide Glasses ◽  
Thermal Transitions ◽  
Stability Range ◽  
Conductivity Enhancement

This review article presents recent studies on nanostructured glass-ceramic materials with substantially improved electrical (ionic or electronic) conductivity or with an extended temperature stability range of highly conducting high-temperature crystalline phases. Such materials were synthesized by the thermal nanocrystallization of selected electrically conducting oxide glasses. Various nanostructured systems have been described, including glass-ceramics based on ion conductive glasses (silver iodate and bismuth oxide ones) and electronic conductive glasses (vanadate-phosphate and olivine-like ones). Most systems under consideration have been studied with the practical aim of using them as electrode or solid electrolyte materials for rechargeable Li-ion, Na-ion, all-solid batteries, or solid oxide fuel cells. It has been shown that the conductivity enhancement of glass-ceramics is closely correlated with their dual microstructure, consisting of nanocrystallites (5–100 nm) confined in the glassy matrix. The disordered interfacial regions in those materials form “easy conduction” paths. It has also been shown that the glassy matrices may be a suitable environment for phases, which in bulk form are stable at high temperatures, and may exist when confined in nanograins embedded in the glassy matrix even at room temperature. Many complementary experimental techniques probing the electrical conductivity, long- and short-range structure, microstructure at the nanometer scale, or thermal transitions have been used to characterize the glass-ceramic systems under consideration. Their results have helped to explain the correlations between the microstructure and the properties of these systems.

scholarly journals Production of Porous Ceramic Materials from Spent Fluorescent Lamps

2021 ◽  
Vol 11 (13) ◽  
pp. 6056
Author(s):  
Egle Rosson ◽  
Acacio Rincón Rincón Romero ◽  
Denis Badocco ◽  
Federico Zorzi ◽  
Paolo Sgarbossa ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
High Speed ◽  
Porous Ceramic ◽  
Ceramic Materials ◽  
Porous Ceramics ◽  
Fluorescent Lamps ◽  
Naoh Solution ◽  
Commercial Glass ◽  
Triton X

Spent fluorescent lamps (SFL) are classified as hazardous materials in the European Waste Catalogue, which includes residues from various hi-tech devices. The most common end-of-life treatment of SFL consists in the recovery of rare earth elements from the phosphor powders, with associated problems in the management of the glass residues, which are usually landfilled. This study involves the manufacturing of porous ceramics from both the coarse glass-rich fraction and the phosphor-enriched fraction of spent fluorescent lamps. These porous materials, realizing the immobilization of Rare Earth Elements (REEs) within a glass matrix, are suggested for application in buildings as thermal and acoustic insulators. The proposed process is characterized by: (i) alkaline activation (2.5 M or 1 M NaOH aqueous solution); (ii) pre-curing at 75 °C; (iii) the addition of a surfactant (Triton X-100) for foaming at high-speed stirring; (iv) curing at 45 °C; (v) viscous flow sintering at 700 °C. All the final porous ceramics present a limited metal leaching and, in particular, the coarse glass fraction activated with 2.5 M NaOH solution leads to materials comparable to commercial glass foams in terms of mechanical properties.

Sign in / Sign up

Export Citation Format

Share Document