Pub Date : 2024-12-01DOI: 10.1016/j.oceram.2024.100713
N.M.P. Truong , M. Michálková , M. Sedano , M.J. Pascual , R. Klement
Glasses of compositions 40SiO2-25Al2O3-18Li2O-7LiF-(10-x-y)YF3-xErF3-yYbF3 (mol.%, x = 0.1, 0.5; y = 0, 0.4, 2, 4) were prepared by melt-quenching technique and milled into powders. Glass powder pellets were treated by hot pressing at defined temperatures to obtain the corresponding glass-ceramics (GCs). High-resolution TEM and XRD analysis revealed the crystallization of LiYF4 and LiAlSiO4 phases with nano-crystal size below 50 nm, resulting in translucent GCs. The density of GCs was 98–99.5 % compared to parent glasses. GCs exhibited intense up-conversion emission when excited by near-infrared light at 980 nm. As Er3+ concentration increased from 0.1 to 0.5 mol.% in the samples, notable enhancement in green and red emission intensities was indicated. Yb3+ ions significantly facilitated up-conversion emission through energy transfer to Er3+ ions, resulting in a higher luminescence yield compared to Er3+ single-doped GCs. The tuning of the red to green emission intensity ratio can be achieved by varying Er3+ and Yb3+ concentrations and Er3+/Yb3+ ratio.
{"title":"Pressure-assisted sintering approaches for up-converting LiYF4:Er/Yb transparent oxyfluoride glass-ceramics","authors":"N.M.P. Truong , M. Michálková , M. Sedano , M.J. Pascual , R. Klement","doi":"10.1016/j.oceram.2024.100713","DOIUrl":"10.1016/j.oceram.2024.100713","url":null,"abstract":"<div><div>Glasses of compositions 40SiO<sub>2</sub>-25Al<sub>2</sub>O<sub>3</sub>-18Li<sub>2</sub>O-7LiF-(10-x-y)YF<sub>3</sub>-xErF<sub>3</sub>-yYbF<sub>3</sub> (mol.%, <em>x</em> = 0.1, 0.5; <em>y</em> = 0, 0.4, 2, 4) were prepared by melt-quenching technique and milled into powders. Glass powder pellets were treated by hot pressing at defined temperatures to obtain the corresponding glass-ceramics (GCs). High-resolution TEM and XRD analysis revealed the crystallization of LiYF<sub>4</sub> and LiAlSiO<sub>4</sub> phases with nano-crystal size below 50 nm, resulting in translucent GCs. The density of GCs was 98–99.5 % compared to parent glasses. GCs exhibited intense up-conversion emission when excited by near-infrared light at 980 nm. As Er<sup>3+</sup> concentration increased from 0.1 to 0.5 mol.% in the samples, notable enhancement in green and red emission intensities was indicated. Yb<sup>3+</sup> ions significantly facilitated up-conversion emission through energy transfer to Er<sup>3+</sup> ions, resulting in a higher luminescence yield compared to Er<sup>3+</sup> single-doped GCs. The tuning of the red to green emission intensity ratio can be achieved by varying Er<sup>3+</sup> and Yb<sup>3+</sup> concentrations and Er<sup>3+</sup>/Yb<sup>3+</sup> ratio.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100713"},"PeriodicalIF":2.9,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-01DOI: 10.1016/j.oceram.2024.100715
Hongqiang Ma , Enyang Dai , Guangxue Liu , Xinhua Yuan , Jialong Wu , Jingjing Feng
MgO-based cementitious materials are an important direction of green, low-carbon and sustainable cementitious materials. This paper investigates the hydration characteristics of MgO-activated slag binder under the influence of carbonate and silicate. The results show that the combination of silica fume and Na2CO3 is more effective in obtaining lower pore structure and refining microstructure than using silica fume or Na2CO3 alone. The pore volume (<1000 nm) of the MgO-activated slag binder curing for 28d is reduced by nearly 80 % compared with 3d The addition of the small amount of SF reduces the content of bulk crystalline hydrotalcite and the content of bound and interlayer water in the gelling phase and promotes the generation of M-S-H gel phase. Controlling the type and content of multiple carbonates and silicate gel phases in preparing MgO-aluminosilicates binder can achieve better results in reducing the pore volume, refining the pore structure, and increasing the compressive strength.
{"title":"Effect of carbonate and silicate on the microstructural properties of the MgO-activated slag binder","authors":"Hongqiang Ma , Enyang Dai , Guangxue Liu , Xinhua Yuan , Jialong Wu , Jingjing Feng","doi":"10.1016/j.oceram.2024.100715","DOIUrl":"10.1016/j.oceram.2024.100715","url":null,"abstract":"<div><div>MgO-based cementitious materials are an important direction of green, low-carbon and sustainable cementitious materials. This paper investigates the hydration characteristics of MgO-activated slag binder under the influence of carbonate and silicate. The results show that the combination of silica fume and Na<sub>2</sub>CO<sub>3</sub> is more effective in obtaining lower pore structure and refining microstructure than using silica fume or Na<sub>2</sub>CO<sub>3</sub> alone. The pore volume (<1000 nm) of the MgO-activated slag binder curing for 28d is reduced by nearly 80 % compared with 3d The addition of the small amount of SF reduces the content of bulk crystalline hydrotalcite and the content of bound and interlayer water in the gelling phase and promotes the generation of M-S-H gel phase. Controlling the type and content of multiple carbonates and silicate gel phases in preparing MgO-aluminosilicates binder can achieve better results in reducing the pore volume, refining the pore structure, and increasing the compressive strength.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"21 ","pages":"Article 100715"},"PeriodicalIF":2.9,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143160276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-29DOI: 10.1016/j.oceram.2024.100714
Siddhartha Roy
Porous ceramics combine excellent properties, such as being lightweight, having good mechanical strength and wear behavior, outstanding high-temperature properties, resistance to thermal shock and corrosion, etc. To further enhance their properties and broaden their applications, porous ceramic composites have been developed in recent years by combining at least two different ceramic phases in the porous material, with each maintaining its individual physical and chemical properties separated by a distinct interface. Apart from their superior properties over single-phase porous ceramics, they also offer tailorable composition and microstructure. Accordingly, porous ceramic composites already find applications in diverse areas, such as bone scaffolds, radome materials, electromagnetic shielding applications, filters and membranes, etc., and newer applications are being explored. In this maiden review on porous ceramic composites, different properties and application areas of porous ceramic composites have been critically reviewed, and research areas have been identified for further development.
{"title":"Properties and advanced applications of porous ceramic composites","authors":"Siddhartha Roy","doi":"10.1016/j.oceram.2024.100714","DOIUrl":"10.1016/j.oceram.2024.100714","url":null,"abstract":"<div><div>Porous ceramics combine excellent properties, such as being lightweight, having good mechanical strength and wear behavior, outstanding high-temperature properties, resistance to thermal shock and corrosion, etc. To further enhance their properties and broaden their applications, porous ceramic composites have been developed in recent years by combining at least two different ceramic phases in the porous material, with each maintaining its individual physical and chemical properties separated by a distinct interface. Apart from their superior properties over single-phase porous ceramics, they also offer tailorable composition and microstructure. Accordingly, porous ceramic composites already find applications in diverse areas, such as bone scaffolds, radome materials, electromagnetic shielding applications, filters and membranes, etc., and newer applications are being explored. In this maiden review on porous ceramic composites, different properties and application areas of porous ceramic composites have been critically reviewed, and research areas have been identified for further development.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"21 ","pages":"Article 100714"},"PeriodicalIF":2.9,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143160359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ultra-thin glass with a thickness of 100 µm or below is an attractive substrate for sputter deposition of thin films. However, research has shown that the deposition of functional coatings is often correlated with a significant strength reduction of the underlying glass.
This study aims to identify relevant thin film properties that influence the ultra-thin glass strength using the example of indium tin oxide. For that, thin films with varying properties were sputter-deposited on ultra-thin glass. Then, correlations between glass strength and surface roughness, film morphology, and thin film stress were analyzed.
It could be shown that the thin film stress and the film morphology are of major importance regarding the strength of the coated ultra-thin glass. In contrast, the surface roughness is expected to be of minor importance. Different models of the interaction between thin film and existing flaws in the glass are suggested to explain the experimental data.
{"title":"The influence of sputter-deposited indium tin oxide thin films on the strength of ultra-thin glass","authors":"Wiebke Langgemach , Matthias Fahland , Edda Rädlein","doi":"10.1016/j.oceram.2024.100710","DOIUrl":"10.1016/j.oceram.2024.100710","url":null,"abstract":"<div><div>Ultra-thin glass with a thickness of 100<!--> <!-->µm or below is an attractive substrate for sputter deposition of thin films. However, research has shown that the deposition of functional coatings is often correlated with a significant strength reduction of the underlying glass.</div><div>This study aims to identify relevant thin film properties that influence the ultra-thin glass strength using the example of indium tin oxide. For that, thin films with varying properties were sputter-deposited on ultra-thin glass. Then, correlations between glass strength and surface roughness, film morphology, and thin film stress were analyzed.</div><div>It could be shown that the thin film stress and the film morphology are of major importance regarding the strength of the coated ultra-thin glass. In contrast, the surface roughness is expected to be of minor importance. Different models of the interaction between thin film and existing flaws in the glass are suggested to explain the experimental data.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"21 ","pages":"Article 100710"},"PeriodicalIF":2.9,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143160274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-19DOI: 10.1016/j.oceram.2024.100711
Muthukumar Abishek , Marija Prekajski Đorđević , Svetlana Butulija , Branko Matović , Ravi Kumar
Two compositionally complex oxides (CCOs) of the type (Hf0.2Zr0.2Ce0.2Gd0.2 RE0.2)O2-δ, were synthesized via self-propagating room temperature synthesis where RE=Yb for one of the two, while in the other case, Yb was replaced by equal concentrations of Pr and Nd. Heat-treatment at varied temperatures between 900 °C – 1500 °C and phase evolution studies revealed the formation of a single phase with a FCC structure with the Yb containing oxide. However, the substitution of Yb with Pr and Nd resulted in an additional secondary FCC phase. Furthermore, Raman spectroscopy confirmed pyrochlore-type ordering in both compounds with exemplification of superlattice planes in high-resolution transmission electron microscopic images. The presence of 3+ and 4+ cations confirmed by X-ray photoelectron spectroscopy, is in accordance with the results on the pyrochlore structure containing two different cationic species.
{"title":"Self-propagating room temperature synthesis and structural characterization of transition metal-rare earth based compositionally complex oxides","authors":"Muthukumar Abishek , Marija Prekajski Đorđević , Svetlana Butulija , Branko Matović , Ravi Kumar","doi":"10.1016/j.oceram.2024.100711","DOIUrl":"10.1016/j.oceram.2024.100711","url":null,"abstract":"<div><div>Two compositionally complex oxides (CCOs) of the type (Hf<sub>0.2</sub>Zr<sub>0.2</sub>Ce<sub>0.2</sub>Gd<sub>0.2</sub> RE<sub>0.2</sub>)O<sub>2-δ,</sub> were synthesized via self-propagating room temperature synthesis where RE=Yb for one of the two, while in the other case, Yb was replaced by equal concentrations of Pr and Nd. Heat-treatment at varied temperatures between 900 °C – 1500 °C and phase evolution studies revealed the formation of a single phase with a FCC structure with the Yb containing oxide. However, the substitution of Yb with Pr and Nd resulted in an additional secondary FCC phase. Furthermore, Raman spectroscopy confirmed pyrochlore-type ordering in both compounds with exemplification of superlattice planes in high-resolution transmission electron microscopic images. The presence of 3+ and 4+ cations confirmed by X-ray photoelectron spectroscopy, is in accordance with the results on the pyrochlore structure containing two different cationic species.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100711"},"PeriodicalIF":2.9,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-19DOI: 10.1016/j.oceram.2024.100705
Johannes Schubert , Pascal Friederich , Benedikt Burchard , Frederik Zanger
Additive manufacturing by vat photopolymerization (VPP) enables the flexible production of ceramic components. The process requires ceramic slurries consisting of a photosensitive binder system and ceramic powder. To prevent defects during debinding and sintering, the highest possible content of ceramic particles is desired. At the same time, a certain viscosity must not be exceeded to ensure the processability in the VPP process. This conflict of objectives requires a precise adjustment of the large amount of slurry constituents. Hence, an experimental slurry development and optimization is very expensive and time-consuming. Therefore, Bayesian optimization, an artificial intelligence (AI) approach, was used to enhance an experimental optimization of the slurry composition. Using this approach, it was possible to achieve in less than 40 optimization steps an aluminum oxide (Al2O3) slurry suitable for VPP with a content of 65 vol.% ceramic powder, the highest currently known fraction for Al2O3 in VPP slurries.
{"title":"Development of aluminum oxide slurries for additive manufacturing by Bayesian optimization","authors":"Johannes Schubert , Pascal Friederich , Benedikt Burchard , Frederik Zanger","doi":"10.1016/j.oceram.2024.100705","DOIUrl":"10.1016/j.oceram.2024.100705","url":null,"abstract":"<div><div>Additive manufacturing by vat photopolymerization (VPP) enables the flexible production of ceramic components. The process requires ceramic slurries consisting of a photosensitive binder system and ceramic powder. To prevent defects during debinding and sintering, the highest possible content of ceramic particles is desired. At the same time, a certain viscosity must not be exceeded to ensure the processability in the VPP process. This conflict of objectives requires a precise adjustment of the large amount of slurry constituents. Hence, an experimental slurry development and optimization is very expensive and time-consuming. Therefore, Bayesian optimization, an artificial intelligence (AI) approach, was used to enhance an experimental optimization of the slurry composition. Using this approach, it was possible to achieve in less than 40 optimization steps an aluminum oxide (Al<sub>2</sub>O<sub>3</sub>) slurry suitable for VPP with a content of 65 vol.% ceramic powder, the highest currently known fraction for Al<sub>2</sub>O<sub>3</sub> in VPP slurries.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100705"},"PeriodicalIF":2.9,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-19DOI: 10.1016/j.oceram.2024.100706
Jessica Lippert, Marcela Arango-Ospina, Aldo R. Boccaccini
Bioactive glasses (BGs) are highly researched biomaterials in the field of bone tissue engineering. Besides their good biocompatibility and biodegradability, they also develop osteogenic and angiogenic effects due to the release of several biologically active ions through the dissolution process. To further improve the functionality of BGs, different biomolecules can be added, which are then released into the body together with the BG ionic dissolution products. For this purpose, phytotherapeutic agents can be used, which have the potential advantage of inducing less undesirable side effects than synthetic drugs and can exhibit anti-inflammatory and antibacterial activity. A well-known example of such natural compounds is the Manuka honey from New Zealand, which was used in this project. The aim of this study was thus to investigate the synergistic effects of the dissolution products of bioactive glasses in combination with Manuka honey (MH). Different relevant bioactive glass compositions (45S5 BG, 13–93 BG and 0106-B1 BG) were combined with MH. Cell biology (osteoblast-like cell line MG-63) and antibacterial assays (E. coli and S. aureus) were performed. The results indicated synergistic effects of BGs and MH, particularly in relation to the antibacterial activity of BG-MH combinations, which resulted in overall bacteria viabilities of < 40% compared to 80% of viable bacteria for BG samples without MH. Interestingly, the ionic dissolution products from 13-93 BG and 0106-B1 BG showed superior effects on MG-63 cells when combined with MH compared with 45S5 BG at the same concentrations. These findings suggest that combining BGs with MH enhances the stimulatory effects on cells and bacteria, supporting the potential use of BGs in combination with natural compounds for tissue engineering applications.
{"title":"Study of the synergistic effects of bioactive glasses with Manuka honey","authors":"Jessica Lippert, Marcela Arango-Ospina, Aldo R. Boccaccini","doi":"10.1016/j.oceram.2024.100706","DOIUrl":"10.1016/j.oceram.2024.100706","url":null,"abstract":"<div><div>Bioactive glasses (BGs) are highly researched biomaterials in the field of bone tissue engineering. Besides their good biocompatibility and biodegradability, they also develop osteogenic and angiogenic effects due to the release of several biologically active ions through the dissolution process. To further improve the functionality of BGs, different biomolecules can be added, which are then released into the body together with the BG ionic dissolution products. For this purpose, phytotherapeutic agents can be used, which have the potential advantage of inducing less undesirable side effects than synthetic drugs and can exhibit anti-inflammatory and antibacterial activity. A well-known example of such natural compounds is the Manuka honey from New Zealand, which was used in this project. The aim of this study was thus to investigate the synergistic effects of the dissolution products of bioactive glasses in combination with Manuka honey (MH). Different relevant bioactive glass compositions (45S5 BG, 13–93 BG and 0106-B1 BG) were combined with MH. Cell biology (osteoblast-like cell line MG-63) and antibacterial assays (<em>E. coli</em> and <em>S. aureus</em>) were performed. The results indicated synergistic effects of BGs and MH, particularly in relation to the antibacterial activity of BG-MH combinations, which resulted in overall bacteria viabilities of < 40% compared to 80% of viable bacteria for BG samples without MH. Interestingly, the ionic dissolution products from 13-93 BG and 0106-B1 BG showed superior effects on MG-63 cells when combined with MH compared with 45S5 BG at the same concentrations. These findings suggest that combining BGs with MH enhances the stimulatory effects on cells and bacteria, supporting the potential use of BGs in combination with natural compounds for tissue engineering applications.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"21 ","pages":"Article 100706"},"PeriodicalIF":2.9,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-17DOI: 10.1016/j.oceram.2024.100709
Durgaprasad D. Ramteke , Miroslava Hujova , Jozef Kraxner , Dusan Galusek , Hamada Elsayed , Paolo Colombo , Enrico Bernardo
Discarded soda-lime glass (SLG) may contain small amounts of ceramic, metallic, and polymeric contaminants, therefore recycling of this material is far from ideal. The quality of newly made glass products made by remelting of cullet, as a result, declines. Consolidation at low temperatures to form materials similar to geopolymers could enable the complete re-use of contaminated cullet. SLG powders, either as received or after pre-washing in an acid solution, were added to a sodium aluminate solution and mechanically stirred at a low speed for three hours at room temperature. The formation of microporous semi-crystalline monoliths involved suspensions casting into plastic molds, followed by an overnight cure at 75 °C. The monoliths prepared from both untreated SLG particles and pre-washed SLG particles contained crystalline phases of zeolite LTA and hydrosodalite. The mechanical characteristics showed good agreement with the properties of cementitious materials, with compressive strength ranging from 22 to 29 MPa and flexural strength ranging from 13.2 to 19.9 MPa. Furthermore, the technique effectively produced Venetian terrazzo-like samples by adding coarse glass particles as fillers with particle sizes of up to 3 mm, which could lead to significant material and energy savings in their fabrication. The suggested method could be expanded to include other challenging-to-reuse glass formulations, providing attractive and versatile recycled materials.
{"title":"Attack of discarded soda-lime glass with sodium aluminate for the manufacturing of sustainable geopolymer components","authors":"Durgaprasad D. Ramteke , Miroslava Hujova , Jozef Kraxner , Dusan Galusek , Hamada Elsayed , Paolo Colombo , Enrico Bernardo","doi":"10.1016/j.oceram.2024.100709","DOIUrl":"10.1016/j.oceram.2024.100709","url":null,"abstract":"<div><div>Discarded soda-lime glass (SLG) may contain small amounts of ceramic, metallic, and polymeric contaminants, therefore recycling of this material is far from ideal. The quality of newly made glass products made by remelting of cullet, as a result, declines. Consolidation at low temperatures to form materials similar to geopolymers could enable the complete re-use of contaminated cullet. SLG powders, either as received or after pre-washing in an acid solution, were added to a sodium aluminate solution and mechanically stirred at a low speed for three hours at room temperature. The formation of microporous semi-crystalline monoliths involved suspensions casting into plastic molds, followed by an overnight cure at 75 °C. The monoliths prepared from both untreated SLG particles and pre-washed SLG particles contained crystalline phases of zeolite LTA and hydrosodalite. The mechanical characteristics showed good agreement with the properties of cementitious materials, with compressive strength ranging from 22 to 29 MPa and flexural strength ranging from 13.2 to 19.9 MPa. Furthermore, the technique effectively produced Venetian terrazzo-like samples by adding coarse glass particles as fillers with particle sizes of up to 3 mm, which could lead to significant material and energy savings in their fabrication. The suggested method could be expanded to include other challenging-to-reuse glass formulations, providing attractive and versatile recycled materials.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100709"},"PeriodicalIF":2.9,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A new group of boro-tellurite glasses (BCa20, BCa17, BCa14, BCa11) was fabricated using the melt quench method for potential radiation shielding and optical applications. The mechanical, optical, and radiation shielding properties were studied with varying oxide compositions. A decrease in B2O3 and CaO content, with increasing TeO2, led to a reduction in elastic modulus and bulk modulus (from 69.638 to 61.331 GPa), as well as a decrease in packing density (0.673 to 0.636). The optical band gap also gradually reduced (from 3.637 to 3.504 eV), while Urbach energy increased (from 0.293 to 0.354 eV). Optical basicity increased, and optical electronegativity decreased, indicating a shift toward ionic bonding and reduced glass stability. Radiation shielding performance improved with the addition of TeO2, as confirmed by the linear attenuation coefficient (LAC) results using Phy-X software. These findings suggest potential for these glasses in radiation shielding and optical material applications.
{"title":"Development of and study of boro-tellurite glasses for optical and radiation shielding applications","authors":"M.I. Sayyed , M.H.A. Mhareb , Heryanto heryanto , Yasser Maghrbi","doi":"10.1016/j.oceram.2024.100708","DOIUrl":"10.1016/j.oceram.2024.100708","url":null,"abstract":"<div><div>A new group of boro-tellurite glasses (BCa20, BCa17, BCa14, BCa11) was fabricated using the melt quench method for potential radiation shielding and optical applications. The mechanical, optical, and radiation shielding properties were studied with varying oxide compositions. A decrease in B<sub>2</sub>O<sub>3</sub> and CaO content, with increasing TeO<sub>2</sub>, led to a reduction in elastic modulus and bulk modulus (from 69.638 to 61.331 GPa), as well as a decrease in packing density (0.673 to 0.636). The optical band gap also gradually reduced (from 3.637 to 3.504 eV), while Urbach energy increased (from 0.293 to 0.354 eV). Optical basicity increased, and optical electronegativity decreased, indicating a shift toward ionic bonding and reduced glass stability. Radiation shielding performance improved with the addition of TeO<sub>2</sub>, as confirmed by the linear attenuation coefficient (LAC) results using Phy-X software. These findings suggest potential for these glasses in radiation shielding and optical material applications.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100708"},"PeriodicalIF":2.9,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-14DOI: 10.1016/j.oceram.2024.100707
Michael W. Mervosh , Sevag Momjian , Javier Mena-Garcia , Clive A. Randall
Conventional varistors rely on the formation of a Double Schottky Barrier within the intergranular region of ZnO via acceptor doping and a Bi2O3 phase. This work has been able to yield varistor-like behavior via cold sintered ZnO composites by placing 2D hBN flakes on the grain boundaries within the ZnO matrix. Above the percolation threshold, a network of resistive hBN barriers is formed which prevents current from flowing through the more conductive ZnO. However, at a given voltage, electrons can tunnel through the hBN if the layers are kept thin enough. Within this narrow band of hBN content, samples have been fabricated with α values as high as 9.5. The composite system demonstrated Schottky conduction at low fields before switching to Fowler-Nordheim tunneling at high fields. This microstructural design was able to show greater nonlinearity compared to previous attempts at creating varistor materials through the unique cold sintering process (CSP).
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