Journal of the American Ceramic Society最新文献

{"title":"Synchrotron X-ray and neutron scattering studies of in situ heated BaO·2SiO2 glasses","authors":"Fangzheng Chen,&nbsp;Xinsheng Xia,&nbsp;Matthew E. McKenzie,&nbsp;K. F. Kelton","doi":"10.1111/jace.20588","DOIUrl":"https://doi.org/10.1111/jace.20588","url":null,"abstract":"<p>Synchrotron X-ray scattering and neutron scattering experiments are used to study structural changes in BaO∙2SiO₂ glasses that were in situ isothermally heated at multiple temperatures. The temperatures selected cover the nucleation temperature range in this glass. No systematic trend in the scattering results was observed as a function of either temperature or isothermal time in the neutron scattering results. In the synchrotron X-ray scattering experiments, the peak heights of the structure factor increased with increasing annealing time, indicating structural ordering, but only at the lowest temperature. A technique that jointly combines reverse Monte Carlo and molecular dynamics simulations is used to reveal the source of the structural ordering with annealing.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Er3+-doped amorphous tellurite thin films","authors":"Pradeep Ramanan,&nbsp;Jan Gutwirth,&nbsp;Stanislav Slang,&nbsp;Anupama Viswanathan,&nbsp;Taghrid Ghanawi,&nbsp;Florent Starecki,&nbsp;Virginie Nazabal,&nbsp;Matthieu Roussey,&nbsp;Petr Němec,&nbsp;Laeticia Petit","doi":"10.1111/jace.20589","DOIUrl":"https://doi.org/10.1111/jace.20589","url":null,"abstract":"<p>Radio-frequency (RF) magnetron sputtering was used to deposit amorphous tellurite thin films from glassy targets from TeO₂–ZnO–Na₂O/BaO/Bi₂O₃ system doped with 2.5 mol% of Er₂O₃. The impact of the sputtering power on the optical, luminescence, and structural properties of the films is discussed. The deposition process leads to amorphous and transparent films which emit light in the visible and near-infrared confirming the presence of Er³⁺ in the films’ network. Owing to their large refractive index and stability overtime, the Bi containing films are potential materials for integrated photonics and optical switches.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jace.20589","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Achieving high piezoelectric performance and enhanced high-temperature resistivity in CaBi2Nb2O9-based textured ceramics","authors":"Chenyu Qiu,&nbsp;Yike Wang,&nbsp;Ruoqi Jin,&nbsp;Liqing Hu,&nbsp;Zhuo Xu,&nbsp;Liwei D. Geng,&nbsp;Yongke Yan","doi":"10.1111/jace.20587","DOIUrl":"https://doi.org/10.1111/jace.20587","url":null,"abstract":"<p>CaBi₂Nb₂O₉ (CBN) ceramics exhibit extremely high Curie temperature, but the low high-temperature resistivity and low piezoelectric properties in ceramics limit their application in high-temperature sensors. In this work, the effect of W⁶⁺ donor doping on dielectric, ferroelectric, piezoelectric properties, and resistivity of CBN ceramics were systemically investigated. In the 2 mol% W⁶⁺-doped CBN ceramics (CBNW-2), the piezoelectric constant (from 6.6 to 14.3 pC/N) and the high-temperature resistivity (from 5.8 × 10⁴ to 7.8 × 10⁵ Ω·cm at 600°C) were significantly increased. To further improve the piezoelectric properties, we fabricated textured CBNW-2 with a high Lotgering factor (<i>f</i>) of 97.1% by the templated grain growth method. The textured CBNW-2 ceramics exhibit strong piezoelectric anisotropy. Piezoelectric constant perpendicular to the texture direction (<i>d</i>_33⊥) increases significantly to 23 pC/N, but the piezoelectric constant parallel to the texture direction (<i>d</i>_33∥) is only 0.9 pC/N, resulting in a large <i>d</i>_33⊥/<i>d</i>_33∥ of 25.6. The significant enhancement in <i>d</i>_33⊥ can be attributed to the substantial increase in remnant polarization, which is given by the highly oriented grain arrangement. Besides, <i>d</i>₃₃ after annealing at 900°C remained 21.4 pC/N and the resistivity at 600°C reached 5.7 × 10⁵ Ω·cm. The excellent piezoelectric properties and high-temperature resistivity of the textured CBNW-2 ceramics indicate that it is a promising piezoelectric material for high-temperature applications.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molten salts synthesized L-Ta2O5:Er3+/Yb3+ with superior pure green upconversion luminescence","authors":"Yuhan Fan,&nbsp;Yongze Cao,&nbsp;Meiling Li,&nbsp;Guojian Li,&nbsp;Shang Sun,&nbsp;Yichao Wang,&nbsp;Xu Sai,&nbsp;Jinsu Zhang,&nbsp;Baojiu Chen","doi":"10.1111/jace.20583","DOIUrl":"https://doi.org/10.1111/jace.20583","url":null,"abstract":"<p>L-Ta₂O₅:Er³⁺/Yb³⁺ upconversion phosphors were synthesized by employing the molten salts method with B₂O₃ as solvent. The optimal doping concentrations of Er³⁺ and Yb³⁺ are 0.2 and 2.5 mol%, respectively. The green upconversion luminescence (UCL) integral intensity of the acid-pickling sample reached 40% of β-NaYF₄:Er³⁺/Yb³⁺ under 980 nm laser excitation. Er³⁺/Yb³⁺ may take the sites of Ta⁵⁺ and insert into the interlayers of L-Ta₂O₅. Using the luminescence intensity ratio (LIR) technique, the relative temperature sensitivity was obtained to be 0.95 %K⁻¹ at 303 K. L-Ta₂O₅:Er³⁺/Yb³⁺ with outstanding pure green UCL intensity and high-temperature sensitivity can be applied to luminescence display and temperature sensing.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation of dense B4C ceramics via epoxy system gelcasting and different sintering methods","authors":"Xiaoqing Zhao,&nbsp;Bin Wang,&nbsp;Ji Zou,&nbsp;Ping He,&nbsp;Zihao Zhang,&nbsp;Shuo Liu,&nbsp;Yihan Qi,&nbsp;Weimin Wang,&nbsp;Zhengyi Fu","doi":"10.1111/jace.20579","DOIUrl":"https://doi.org/10.1111/jace.20579","url":null,"abstract":"<p>Gelcasting is proven effective for the mass production of large-sized and complex-shaped B₄C ceramics. In this study, the uniform B₄C green body with a relative density of 54.17% and compressive strength of 13.37 MPa was prepared by epoxy gelcasting. The nonlinear drying process of the epoxy system was investigated by real-time monitoring, which guided the preparation route to prevent green bodies defects. Two sintering methods, spark plasma sintering (SPS) and pressureless sintering, were employed to densify the B₄C green bodies. Due to the high quality of green body obtained by gelcasting, B₄C ceramics with a dense and fine-grained microstructure were successfully prepared via SPS at 1700°C. When the B₄C ceramics was pressureless sintered alone at 2250°C, their densification were failed and instead caused abnormal grain growth. By incorporating TiB₂, the pressureless sintering of B₄C at 2100°C basically achieved densification, reaching a relative density of 95.04%. The gelcasting process enabled uniform distribution of TiB₂ grains in the B₄C matrix, which not only inhibited grains growth, but also promoted the sintering ability of B₄C ceramics. These results provide valuable insights into the epoxy gelation of B₄C ceramics, showing potential for large-scale production of complex-shaped B₄C ceramics at relatively low sintering temperatures.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Re3+ radius on phase composition and thermal sensitivity of Ba4.5Re9Ti18O54 ceramics","authors":"Ruifeng Wu,&nbsp;Yafei Liu,&nbsp;Hao Sun,&nbsp;Jianan Xu,&nbsp;Jia Chen,&nbsp;Aimin Chang,&nbsp;Bo Zhang","doi":"10.1111/jace.20574","DOIUrl":"https://doi.org/10.1111/jace.20574","url":null,"abstract":"<p>Tungsten-bronze materials are widely used in the fields of electro-optic, photorefractive, pyroelectric, millimeter-wave, and piezoelectric devices. In particular, tungsten-bronze Ba_4.5Sm₉Ti₁₈O₅₄ is believed to be useful for fabricating high-temperature thermistors owing to its semiconductor properties. However, inherent shortcomings such as poor linearity (electrical properties deviate from the Arrhenius equation) and high aging coefficients limit the practical applications of these materials. Incorporating rare-earth (<i>Re</i>) ions is an effective means of improving the electrical properties of thermistor materials. In this study, we explore the phase composition and thermosensitive properties of Ba_4.5Re₉Ti₁₈O₅₄ (Re = Y, La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Lu) ceramics with tungsten–bronze structures. The results indicate that the tungsten–bronze phase (Ba_4.5Re₉Ti₁₈O₅₄) is generated when the radius of the <i>Re</i>³⁺ ion exceeds 1.04 Å and the tolerance factor surpasses 0.82. Conversely, a pyrochlore phase (Re₂Ti₂O₇) accompanied by a monoclinic impurity phase (BaTi₂O₅), is formed. Moreover, all Ba_4.5Re₉Ti₁₈O₅₄ ceramics with a tungsten-bronze structure exhibit exceptional linear electrical properties (<i>R</i>² ≥ 999.09‰) and high sensitivity coefficients (<i>α</i>_1000°C ≥ −0.79%/K). In particular, after aging at 1100°C for 600 h, both the aging coefficient and drift rate of material constant are as low as 5.76% and 1.79%, respectively. These results indicate that Ba_4.5Re₉Ti₁₈O₅₄ ceramics are promising for high-temperature and high-accuracy temperature measurements.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adjustable ferrite amount for various characteristics of Ni0.5Cd0.5Fe2O4 nanoparticles incorporated in a SiO2 matrix","authors":"Thomas Dippong,&nbsp;Oana Cadar","doi":"10.1111/jace.20582","DOIUrl":"https://doi.org/10.1111/jace.20582","url":null,"abstract":"<div>\u0000 \u0000 <p>The (Ni_0.5Cd_0.5Fe₂O₄)<i>_x</i>(SiO₂)_100‒<i>_x</i> (<i>x</i> = 0%‒100%) samples were synthesized through sol‒gel technique followed by the study of the evolution of crystalline phases at different temperatures. For the samples containing ferrite, the X-ray diffraction indicated the development of ferrite and SiO₂ matrix and displayed single, low crystallized ferrite at low temperatures and well-crystallized ferrite attended by Fe₂O₃ and SiO₂ at high temperatures (1000°C). The crystallite size and lattice parameter increased with annealing temperature and the amount of ferrite incorporated in the SiO₂ matrix. The evolution of shape, size, and degree of agglomeration with the amount of ferrite incorporated in the SiO₂ matrix at 1000°C were investigated. The values of remanent and saturation magnetizations, anisotropy and coercivity, and the amount of ferrite incorporated in the SiO₂ matrix after annealing at 700°C and 1000°C were correlated with the particle morphology. The SiO₂ matrix exhibited diamagnetic behavior, while the Ni_0.5Cd_0.5Fe₂O₄ incorporated in the SiO₂ matrix showed a superparamagnetic behavior. The amount of ferrite and annealing temperature impacts the particle sizes, which further affects the magnetic characteristics. The incorporation of Ni_0.5Cd_0.5Fe₂O₄ nanoparticles into the inert SiO₂ matrix enabled the control of particle size, minimized particle agglomeration, and enhanced the magnetic properties.</p>\u0000 </div>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the intrinsic sinterability of MgAl2O4 nanopowders","authors":"Shichang Cheng,&nbsp;Hongbing Yang,&nbsp;Weiye Nie,&nbsp;Baoming Wang,&nbsp;Chang-An Wang,&nbsp;Yanhao Dong","doi":"10.1111/jace.20577","DOIUrl":"https://doi.org/10.1111/jace.20577","url":null,"abstract":"<p>Magnesium aluminum spinel MgAl₂O₄ has found applications in transparent ceramics. It is known for poor sinterability, often attributed to slow mass transport kinetics in the literature. The situation can be improved with nanopowders, yet pressureless sintering to 95%–96% (desirable for the final-step hot isostatic pressing, HIP) still requires a homologous temperature <i>T</i>/<i>T</i>_m of about 0.75. Technological solutions to lower the sintering temperature and refine grain size are urgently needed. Here, we proposed that the poor sinterability is partially due to agglomerations of the nanopowders and sought to uncover the intrinsic sinterability. Using commercially available MgAl₂O₄ nanopowders, we demonstrated that the sinterability can be dramatically enhanced with proper deagglomeration treatment and colloidal centrifugal casting. Compared to the control group formed by dry pressing and cold isostatic press, the colloidal process can lower the sintering temperature for full densification by ∼200°C. &gt; 99% relative density can now be achieved at 1350°C for 2 h, that is, at <i>T</i>/<i>T</i>_m= 0.67. &gt; 97% relative density can now be achieved at 1275°C for 2 h, that is, at <i>T</i>/<i>T</i>_m= 0.64. Our work shows that commercial nano-sized MgAl₂O₄ powders with proper treatments and forming techniques can be readily sintered at low temperatures to reach closed porosity while maintaining fine grain size below 200 nm. The results reported here are encouraging for the development of ultrafine-grained MgAl₂O₄ transparent ceramics with lowered HIP temperature.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamic description of the Na2O─CaO─SiO2 system and its application to solidification and heat treatment design","authors":"Lianfeng Yang,&nbsp;Yinping Zeng,&nbsp;Olga Fabrichnaya,&nbsp;Ligang Zhang,&nbsp;Yuling Liu,&nbsp;Yong Du","doi":"10.1111/jace.20565","DOIUrl":"https://doi.org/10.1111/jace.20565","url":null,"abstract":"<p>The Na₂O─CaO─SiO₂ ternary system, which is a very complex pseudo-ternary system, is a fundamental system widely used as glasses and glass–ceramics. Its thermodynamic description is crucial for understanding solidification and subsequent heat treatments. In this work, a thermodynamic assessment of the Na₂O─CaO─SiO₂ system was conducted by applying the CALPHAD method. The liquid phase in the Na₂O─CaO─SiO₂ system was successfully described by the two-sublattice partially ionic liquid model (Na⁺¹,Ca⁺²)<i>_P</i>(O⁻²,SiO₄⁻⁴,SiO₂)<i>_Q</i> and two new sublattice models of (Na⁺¹,Ca⁺²)₂(Na⁺¹,Va)₁(Si⁺⁴)₁(O⁻²)₄ and (Na⁺¹,Ca⁺²)₂^M1(Va,Na⁺¹)₃^M2(Ca⁺²,Na⁺¹)₃^M3(Ca⁺²)₁^M4(Si⁺⁴)₆(O⁻²)₁₈ with accurate cation distributions in their sublattices were developed to respectively describe the ternary solid solution phases βN1C1S1 and Combeite in this work. The other ternary compounds were treated as stoichiometric ones due to their limited solid solubilities. Based on the reliable experimental data, a set of self-consistent thermodynamic parameters was obtained. The calculated isothermal sections, vertical sections, liquidus projection, and thermodynamic properties can satisfactorily reproduce the experimental data within the experimental errors. In addition, the present thermodynamic description contributes to the reliable prediction for the melting temperatures and primary crystallization phases for the Na₂O─CaO─SiO₂ glasses, providing valuable insights for the design of glass and glass–ceramics compositions and heat treatment processes.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The synergetic modification on ionic conductivity and air stability of Ga3+ and Ta5+ co-doped Li7La3Zr2O12 (LLZO)","authors":"Run Yu,&nbsp;Yongjin Chen,&nbsp;Chengyu Li,&nbsp;Shaojun Wang,&nbsp;Pengcheng Li,&nbsp;Ruihan Tang,&nbsp;Cong Gao,&nbsp;Chuanlong Lin,&nbsp;Xiang Gao","doi":"10.1111/jace.20576","DOIUrl":"https://doi.org/10.1111/jace.20576","url":null,"abstract":"<p>The garnet-type oxide Li₇La₃Zr₂O₁₂ solid-state electrolytes (SSEs) are considered as a reliable option in all-solid-state lithium batteries (ASSLBs) due to its excellent properties. However, it still faces challenges such as limited ionic conductivity and low air stability. In this work, Ga³⁺ and Ta⁵⁺ co-doped samples Li₇₋₃<i>_x</i>₋<i>_y</i>Ga<i>_x</i>La₃Zr₂₋<i>_y</i>Ta<i>_y</i>O₁₂ (Ga<i>x</i>Ta<i>y</i>-LLZO) synthesized via the solid-state method are demonstrated to stabilize the cubic phase, regulate the concentration of Li vacancies in LLZO, and improving the Li⁺ transport channels. As a result, the Ga0.1Ta0.3-LLZO sample achieves a high conductivity of ∼1 mS cm⁻¹. Furthermore, we discovered that in addition to the previously reported effects of decreasing grain boundary density and the inert LiGaO₂ secondary phase at grain boundaries, the synergistic effect of introducing multiple dopant ions, which enhances lattice stability, is also a key factor contributing to improved air stability. Our findings demonstrate that co-doping strategy with Ga³⁺/Ta⁵⁺ is an effective method for simultaneously enhancing conductivity and air stability of LLZO, laying solid foundation for the application of SSEs in ASSLBs.</p>","PeriodicalId":200,"journal":{"name":"Journal of the American Ceramic Society","volume":"108 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144197557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}