Open Ceramics最新文献

{"title":"Specifics of Al substitution into boron carbide: A DFT study","authors":"Oleksandr Vasiliev,&nbsp;Vladyslav Bilyi","doi":"10.1016/j.oceram.2024.100695","DOIUrl":"10.1016/j.oceram.2024.100695","url":null,"abstract":"<div><div>Boron carbide (B₄C), known for its hardness and low density, is prone to local amorphization under high non-hydrostatic loads, limiting its applications. Aluminum doping is promising due to aluminum's atomic size, fitting into the B₄C crystal lattice, particularly the intericosahedra chain, potentially reducing amorphization. This work uses first-principles calculations to study aluminum placement in B₄C. We examine the potential for Al substitution in the icosahedron and intericosahedra chain, identifying possible locations. Results show that aluminum can't replace atoms in the icosahedron, but substituting one central atom in the intericosahedra chain with aluminum is energetically favorable and likely changes the chain configuration to an angular one. Additionally, aluminum can substitute one carbon in the (C-B-C) chain of B₁₂(C-B-C) boron carbide. Comparative analysis suggests these configurations may coexist. Our study offers a theoretical model that can guide future experimental efforts and provides valuable insights into the structural specifics of aluminum-doped boron carbide.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100695"},"PeriodicalIF":2.9,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433441","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}

{"title":"Yttria-stabilised zirconia and lanthanum cerate granules with YSZ whiskers prepared by spray drying for thermal barrier coatings","authors":"Milan Parchovianský ,&nbsp;Monika Michálková ,&nbsp;Ivana Parchovianská ,&nbsp;Beáta Pecušová ,&nbsp;Dušan Galusek ,&nbsp;Amirhossein Pakseresht","doi":"10.1016/j.oceram.2024.100694","DOIUrl":"10.1016/j.oceram.2024.100694","url":null,"abstract":"<div><div>The aim of this study was to explore the effect of different solid phases and varied amounts of polyvinyl alcohol (PVA) on granule size of plasma-sprayable yttria-stabilised zirconia (YSZ) with YSZ whiskers (YSZ/W) and lanthanum cerate (La₂Ce₂O₇, LC) with YSZ whiskers (LC/W) as composite powders. The initial phase of this study involved the preparation and optimization of a YSZ suspension using varying solid loadings of YSZ powder (ranging from 30 to 75 wt%) and PVA serving as both a binder and dispersant. The suspension was subjected to rigorous optimization procedures to meet the required standards. The suspensions were spray dried, and the resulting granulates were examined using SEM to determine their shape and size. The particle size of YSZ granules increased with increasing solid loading of YSZ in the suspension. The optimum amount of dispersant was found to be 1 wt% related to the weight of solid, while the solid loading was 75 wt% of YSZ. In some cases, excessive YSZ solid loading and dispersant impaired the formation of spherical granules. Composite YSZ/W and LC/W granules were also prepared with spherical, lemon, or irregular shapes, with the whiskers embedded in the YSZ or LC powder.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100694"},"PeriodicalIF":2.9,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421934","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}

{"title":"Improved mechanical and tribological properties of (TiZrHfNbTa)C with the addition of silicon carbide whiskers","authors":"Lenka Ďaková ,&nbsp;Alexandra Kovalčíková ,&nbsp;Monika Hrubovčáková ,&nbsp;Jana Andrejovská ,&nbsp;František Kromka ,&nbsp;Ján Dusza","doi":"10.1016/j.oceram.2024.100693","DOIUrl":"10.1016/j.oceram.2024.100693","url":null,"abstract":"<div><div>Dense (Ti_0.2Zr_0.2Hf_0.2Nb_0.2Ta_0.2)C with up to 10 wt % SiC whisker were prepared by spark plasma sintering. The influence of SiC_w on the microstructure development, mechanical and tribological properties has been investigated. Nanohardness of HEC and SiC_w phases varied between 38 GPa and 40 GPa, and indentation modulus of elasticity was ∼605 GPa. The hardness of the composites increased from 22 GPa to 27 GPa and indentation fracture resistance from 3.55 MPa m^1/2 to 4.59 MPa m^1/2 with increasing SiC_w content. The main toughening mechanisms were crack deflection, crack branching, and crack bridging. The system HEC +5 wt% of SiC_w was found to possess the highest bending strength of 623 ± 25 MPa. The composites exhibited similar coefficients of frictions with around 0.3 and wear rates approximately 1.50 × 10⁻⁶ mm³/N⋅m at 5 N and 2.66 × 10⁻⁶ mm³/N⋅m at 25 N with positive influence of SiC phase on the wear mechanisms.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100693"},"PeriodicalIF":2.9,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421932","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}

{"title":"Promoting the circularity of ceramic materials through cold sintering of aggregates from construction and demolition waste","authors":"Sonia Marín-Cortés ,&nbsp;Mattia Biesuz ,&nbsp;Aida Serrano ,&nbsp;Emanuele De Bona ,&nbsp;Esther Enríquez ,&nbsp;José F. Fernández ,&nbsp;Vincenzo M. Sglavo","doi":"10.1016/j.oceram.2024.100692","DOIUrl":"10.1016/j.oceram.2024.100692","url":null,"abstract":"<div><div>A ceramic composition containing 95 wt% of construction and demolition waste-like material was consolidated by cold sintering process at 200 °C using KOH water solutions as the liquid medium. The relative density of the samples reaches ∼90 % of the theoretical one for process conditions of 600 MPa and 60 min. A post-annealing process at 1100 °C of the as-cold sintered samples causes a slight increase in the relative density and of their mechanical strength compared with conventionally sintered samples at 1100 °C and increases the shape factor of the Weibull distribution, thus increasing the reliability of the component. It is shown that cold sintering of the material avoids its high pyroplasticity, providing low shrinkage and reducing internal defects in the ceramic. This work represents the first exploration of the viability of manufacturing ceramic tiles with high recycled content contributing to the transition to a greener world.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100692"},"PeriodicalIF":2.9,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421931","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}

{"title":"Eco-friendly fabrication of ZnO-TiO2-rGO nanocomposite for efficient adsorption-assisted organic dyes elimination","authors":"Md Elias ,&nbsp;Ehsanur Rahman ,&nbsp;Sonia Akter ,&nbsp;Mohammad Awlad Hossain ,&nbsp;Rumana A. Jahan ,&nbsp;Md Nizam Uddin ,&nbsp;Shakhawat H. Firoz","doi":"10.1016/j.oceram.2024.100691","DOIUrl":"10.1016/j.oceram.2024.100691","url":null,"abstract":"<div><div>The growing interest in combining the photocatalytic properties of semiconductors like ZnO and TiO₂ with the superior electron conduction capabilities of graphene has resulted in the successful synthesis of in-situ reduced graphene oxide (rGO) supported ZnO-TiO₂ nanostructures through a simple microwave-assisted synthesis method. X-ray Diffraction Spectroscopy (XRD), Field Emission Scanning Electron Microscope (FESEM), UV–visible spectroscopy (UV–vis), and Fourier Transform Infrared Spectroscopy (FTIR) were employed to characterize structural, morphological and optical properties as well as surface functional groups of the synthesized products. The XRD measurements of our synthesized samples confirm both structural crystallinity and phase purity, while the FTIR analysis verifies the complete reduction of graphene oxide (GO) to reduced graphene oxide (rGO). The synthesized ternary nanocomposite ZnO-TiO₂-rGO exhibited a remarkable 100 % adsorption-assisted removal efficiency for 20 mg/L methylene blue (MB) dye under ultraviolet light illumination within 120 min, along with a 56 % dye adsorption removal efficiency in the same time interval. In comparison, pure ZnO showed 0 % adsorption and only 31 % photocatalytic efficiency at the similar condition. Remarkably, the ZnO-TiO₂-rGO nanocomposite exhibited exceptional photocatalytic activity mediated by adsorption, achieving complete degradation of MB dye within 5 min under sunlight irradiation. The photocatalytic efficiency and dye adsorption capacity were found to be significantly lower for the anionic dye methyl orange (MO) compared to the cationic MB dye. The study thoroughly investigated the influence of catalyst dose and initial dye concentration on photodegradation. The proposed mechanism indicates that the extensive surface area and numerous active sites on the rGO promote adsorption, which is then followed by degradation through the metal oxides. Overall, the results unveil that the microwave-assisted synthesis of ZnO-TiO₂-rGO nanocomposite is a promising and environmentally friendly approach for efficiently degrading dyes from contaminated wastewater using both UV light and natural sunlight irradiation.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100691"},"PeriodicalIF":2.9,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421930","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}

{"title":"Vat photopolymerization of ultra-porous bioactive glass foams","authors":"Francesco Baino ,&nbsp;Federico Gaido ,&nbsp;Roberta Gabrieli ,&nbsp;Dario Alidoost ,&nbsp;Alessandro Schiavi ,&nbsp;Mehdi Mohammadi ,&nbsp;Martin Schwentenwein ,&nbsp;Dilshat Tulyaganov ,&nbsp;Enrica Verné","doi":"10.1016/j.oceram.2024.100690","DOIUrl":"10.1016/j.oceram.2024.100690","url":null,"abstract":"<div><div>The introduction of additive manufacturing technologies in the field of biomaterials science has opened new horizons for regenerative medicine. In this work, we pushed the potential of vat polymerization to the limit for fabricating ultra-porous bioactive SiO₂-CaO-MgO-P₂O₅-CaF₂-Na₂O glass scaffolds with bone-like architectural characteristics. The tomographic reconstruction of an open-cell foam was used as input file to the printing system and reliably reproduced in all its exquisite details, as assessed by morphological analyses of sintered scaffolds (thickness of single struts 35 μm, exceptionally high porosity around 94 vol%, most pores with size from 500 to 900 μm). Immersion studies in simulated body fluid (SBF) revealed the apatite-forming ability (i.e., in vitro bioactivity) of the scaffolds, the surface of which started being coated by calcium phosphate after just 3 days from the beginning of the experiments. Taken together, these results show great promise for application of such scaffolds in bone defect repair.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100690"},"PeriodicalIF":2.9,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421929","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}

{"title":"Ion-exchange enhancement of borosilicate glass vials for pharmaceutical packaging","authors":"Ahmed Gamal Abd-Elsatar ,&nbsp;Hamada Elsayed ,&nbsp;Hana Kanková ,&nbsp;Branislav Hruška ,&nbsp;Jozef Kraxner ,&nbsp;Enrico Bernardo ,&nbsp;Dušan Galusek","doi":"10.1016/j.oceram.2024.100689","DOIUrl":"10.1016/j.oceram.2024.100689","url":null,"abstract":"<div><div>Pharmaceutical containers for parenteral use, including vials, ampoules, prefilled syringes, and cartridges, are traditionally made of glass. However, the most commonly used type, borosilicate glass, is susceptible to issues such as breakage, corrosion, and delamination, which can jeopardize the safety and efficacy of the enclosed drugs. To address these concerns without compromising the visual or qualitative aspects of borosilicate medical glass vials, this study aimed at the enhancement of their mechanical, chemical, and corrosion resistance. A single ion exchange treatment (IET) in a salt bath of molten KNO₃ at temperatures of 400, 450, and 500 °C for 2, 12, and 24 h was applied. The effects of the ion exchange process performed under different conditions were assessed by measuring Vickers hardness, crushing load, and chemical durability. The mechanical load required to crush full-body vials after the ion exchange process at 500 °C for 2, 12, and 24 h showed an increase in the applied force values (1650 ± 80, 2340 ± 80, and 2325 ± 40 N) compared to untreated vials (1157 ± 20 N).</div><div>No radial cracks were observed on the surface of treated glass vials after indentation, indicating the presence of compressive stresses that prevented the initiation and propagation of cracks. The EDS analysis confirmed an increase in potassium concentration and a decrease in sodium content near the surface of samples modified by ion exchange treatment. The treated samples showed appropriate chemical stability in different acidic, basic, and neutral solutions. Conspicuous changes are noticed in the Raman spectra after IET, specifically in the Q_n species region. The results indicate the potential of the ion exchange treatment in enhancing the properties of borosilicate glass vials by relatively simple and easily scalable techniques.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100689"},"PeriodicalIF":2.9,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421933","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}

{"title":"Synthesis of polycrystalline Ta₂O₅ inverse opal photonic crystal powders and their optical characterization","authors":"Taiki Maekawa ,&nbsp;Hiroyuki Maekawa ,&nbsp;Yuto Ikeda ,&nbsp;Tomoya Onoe ,&nbsp;Geoffrey I.N. Waterhouse ,&nbsp;Kei-ichiro Murai ,&nbsp;Toshihiro Moriga","doi":"10.1016/j.oceram.2024.100688","DOIUrl":"10.1016/j.oceram.2024.100688","url":null,"abstract":"<div><div>Polycrystalline Ta₂O₅ inverse opal (IO) photonic crystal powders were synthesized using PMMA colloidal crystals as sacrificial templates. We prepared Ta₂O₅ IO powders with vibrant structural colors at UV–vis wavelengths. The photonic bandgaps (PBGs) in the Ta₂O₅ IO powders red-shifted as a function of both the macropore diameter and the refractive index of the medium filling the macropores. Owing to their polycrystalline structure, the Ta₂O₅ IO powders exposed PBGs for various FCC facets, making investigation of their optical properties significantly more complex than Ta₂O₅ IO thin films that preferentially expose only (111) planes as studied previously. Due to the overlap of the PBGs from different FCC facets and the defects that cause light scattering, much of the typical angle-dependent structural color observed in IO thin films was lost in the Ta₂O₅ IO powders. This study offers new insights into the optical properties of IO powders.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100688"},"PeriodicalIF":2.9,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442208","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}

{"title":"Assessing the durability performance of geopolymer concrete utilizing fly ash and sugarcane bagasse ash as sustainable binders","authors":"Mohammed Ali M. Rihan ,&nbsp;Richard Ocharo Onchiri ,&nbsp;Naftary Gathimba ,&nbsp;Bernadette Sabuni","doi":"10.1016/j.oceram.2024.100687","DOIUrl":"10.1016/j.oceram.2024.100687","url":null,"abstract":"<div><div>Geopolymer or alkali-activated binders are being recognized as an eco-friendly, sustainable substitute for ordinary Portland cement (OPC). The development of high-performance concrete with improved durability and mechanical properties and the addition of environmentally friendly components is a continuous effort. Therefore, the current work examines the durability of fly ash-sugarcane bagasse ash mechanical characteristics in terms of water absorption, exposure to elevated temperatures, and acid resistance. The mechanical properties of the geopolymer concrete (GPC) and OPC concrete specimens were evaluated after being subjected to elevated temperatures of 200 °C, 400 °C, 600 °C, and 800 °C. The acid resistance was determined by submerging the concrete specimens in 3 % sulfuric acid (H₂SO₄). The acid resistance of the specimens was evaluated through visual inspection, weight variation, and the percentage loss in compressive strength (C_R). According to the study, C_R typically drops as temperature increases from ambient temperature to 800 °C. However, the rate of decline reduced as temperature increased from ambient temperature to 200 °C. Moreover, the GPC specimens showed a strength loss between 13 % and 21 % following 28 days of sulfuric acid immersion. In contrast, exposure to sulfuric acid caused a 51 % drop in strength for the OPC concrete samples.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100687"},"PeriodicalIF":2.9,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142357412","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}

{"title":"Influences of additives on the properties of geopolymer matrix composites (GMCS) for high-temperature applications (1150 °C)","authors":"Quentin Cligny ,&nbsp;Ameni Gharzouni ,&nbsp;Patrice Duport ,&nbsp;Damien Brandt ,&nbsp;Sylvie Rossignol","doi":"10.1016/j.oceram.2024.100685","DOIUrl":"10.1016/j.oceram.2024.100685","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":34140,"journal":{"name":"Open Ceramics","volume":"20 ","pages":"Article 100685"},"PeriodicalIF":2.9,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421928","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}