Article
Materials Science, Ceramics
Berceste Beyribey, Hwan Kim, Joshua Persky
Summary: BaCe0.7Zr0.1Y0.16Zn0.04O3-δ perovskite shows great potential as an electrolyte in industrial steam electrolysis applications, with excellent protonic conductivity and stability, especially at elevated temperatures. The formation/degradation of secondary phases in wet atmospheres is attributed to the formation of Ba(OH)2 and CeO2 around 500 degrees C. This material is a promising candidate for industrial fuel cells and steam electrolysers.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Multidisciplinary
Charles Otieno Ogolla, Yannik Loth, Tobias Haeger, Cedric Kreusel, Manuel Runkel, Thomas Riedl, Benjamin Butz, Anna Katharina Wigger, Stephan Schaeffer, Peter Haring Bolivar
Summary: In this study, THz-sSNOM was used for nanoscale imaging of CsPbBr3 thin films, and the local THz nanoscale conductivity was derived using a scattering model. The analysis of the obtained signals confirmed the presence of halide vacancies (VBr) and Pb-Pb bonds at the CsPbBr3 grain boundaries, which resulted in charge carrier trapping and nonradiative recombination. This study establishes THz-sSNOM as a powerful analysis platform for thin-film semiconductors like LHPs.
Article
Chemistry, Physical
Gunnar Suchaneck, Nikolay Kalanda, Evgenij Artiukh, Marta Yarmolich, Nikolai A. Sobolev
Summary: This study investigated the electrical resistivity in strontium ferromolybdate ceramics and found that the formation of dielectric SrMoO4 shells at the surface of nanograins affects the sign of the temperature coefficient of resistance. The results provide insights into the low-field magnetoresistance and its potential applications in spintronic devices.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Thomas Defferriere, Dino Klotz, Juan Carlos Gonzalez-Rosillo, Jennifer L. M. Rupp, Harry L. Tuller
Summary: The study shows that grain boundary resistance in solid ionic conductors can be decreased by illuminating with above-bandgap light. Experimental results demonstrate the increase in grain boundary conductance of a 3 mol% Gd-doped ceria thin film by approximately 3.5 times at 250 degrees C, with the reduction of activation energy from 1.12 to 0.68 eV under illumination. The discovered opto-ionic effect could potentially contribute to the development of new electrochemical storage and conversion technologies, as well as fast and contactless control or diagnosis of ionic conduction in polycrystalline solids.
Article
Materials Science, Multidisciplinary
Nannan Chen, Haris Ali Khan, Shenxi Li, Jingjing Li
Summary: This study investigated the mechanisms behind the increased electrical conductivity in pure copper joined with aluminum via micro friction stir blind riveted and post-heating. The increase in E3 boundaries and reduction in random grain boundaries were identified as the main contributing factors. While this grain boundary engineering approach led to improved electrical conductivity, high-temperature heating resulted in a significant reduction in microhardness due to strain relief and grain growth.
MATERIALS CHARACTERIZATION
(2021)
Article
Materials Science, Multidisciplinary
Ruben Bueno Villoro, Maxwell Wood, Ting Luo, Hanna Bishara, Lamya Abdellaoui, Duncan Zavanelli, Baptiste Gault, Gerald Jeffrey Snyder, Christina Scheu, Siyuan Zhang
Summary: Complex microstructures in thermoelectric materials can be utilized to optimize their transport properties. In TiCoSb half Heusler compounds, Fe-dopants segregate to grain boundaries, increasing the electrical conductivity and reducing the thermal conductivity. The electrical conductivity of the grain interior and boundaries is calculated, and the atomic structure of grain boundaries is studied. Segregation engineering in fine-grained thermoelectrics is proposed as a new design tool to optimize transport properties while achieving a lower thermal conductivity.
Article
Energy & Fuels
Yuying Yao, Jing Zhang, Hang Su, Yong Li, Nan Li, Ting Nie, Lidan Liu, Xiaodong Ren, Ningyi Yuan, Jianning Ding, Shengzhong (Frank) Liu
Summary: Perovskite solar cells have high efficiency but low stability due to moisture permeation from grain boundaries and defects. A passivation agent called 3,4,5,6-tetrafluorophthalicacid (TFPA) is designed to improve both efficiency and stability. TFPA is found to distribute along grain boundaries, reducing film roughness and facilitating hole transporting. The device with TFPA modification shows outstanding efficiency and stability, with a champion efficiency of 23.70% and maintaining 90% of initial efficiency after 5200 hours.
Review
Chemistry, Physical
Yingzhi Zhou, Jing Wang, Dongxiang Luo, Dehua Hu, Yonggang Min, Qifan Xue
Summary: This article reviews the experimental progress in modulating the thermoelectric performance of halide perovskites (HPs) from the perspective of electrical conductivity optimization. It includes an overview of reports and understanding of ultralow thermal conductivity of different types of HPs, as well as the research progress on improving thermoelectric properties by optimizing their electrical conductivity. The article also points out several problems in halide perovskite-based thermoelectric devices and provides guidelines for further investigations.
Article
Materials Science, Multidisciplinary
Joydeep Datta, Animesh Biswas, Somobrata Acharya, Animesh Layek, Partha Pratim Ray
Summary: This study investigates the morphological impact of hydrothermally derived CdO on charge conduction and relaxation using bias-dependent impedance spectroscopy. The findings highlight the influence of CdO grain and grain boundaries on the frequency-dependent electric conductivity and relaxation mechanism, with the degree of impact being dependent on the crystallite size. Two different crystallite size-based CdOs are prepared through hydrothermal methods at different temperatures. Materials characterization is conducted through XRD, FESEM, and UV-vis absorption spectra. DC conductivity is evaluated through current-voltage characteristics and bias-dependent impedance spectroscopy at room temperature, revealing the dominance of CdO with larger crystallite size in the conduction mechanism.
MATERIALS CHEMISTRY AND PHYSICS
(2023)
Article
Materials Science, Ceramics
Chitrarasu Kaliyaperumal, Sundeep Kumar Marndi, Amirthapandian Sankarakumar, Thangadurai Paramasivam
Summary: The influence of grain size on the electrical properties of nanocrystalline La2Zr2O7 (LZO) ceramics prepared by chemical co-precipitation was investigated. The XRD and Raman scattering analysis confirmed the pyrochlore structure of La2Zr2O7. SEM and XPS were used to study the morphology and chemical composition. Impedance spectroscopy revealed that the conductivity was contributed by both grains and grain boundaries, with a non-Debye nature of conduction. The activation energy for grain conduction was consistent across different grain sizes, while the activation energy for grain boundary conduction decreased with increasing grain size, indicating oxygen ion migration. The conduction mechanism was dominated by non-overlapping small polaron tunneling, and ion-ion correlation increased with larger grain size.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Multidisciplinary
Mengyao Li, Hang Xu, Silei Wang, Chunyu Song, Jitao Li, Yanyan Liu, Haijian Zhang, Chenglong Zheng, Yating Zhang, Jianquan Yao
Summary: The excellent performance of bolometers in the infrared and terahertz regions has attracted great attention. However, the lack of studies on the fine-scale spatial motion of microscopic particles in bolometers has prevented a full understanding of the physical process. Using micro-nano-scale optoelectronic performance correlation measurements, this study describes how prevalent defect states at the grain boundaries decrease current responses. Additionally, the first ion-bolometric detector is demonstrated with a significant photovoltage response to infrared and THz waves, showing great potential for large-area THz imaging applications. The ion-bolometric effect combines the broad spectral characteristics of the bolometer effect with the temperature sensitivity due to ion migration and provides a unique perspective on detector technology.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Daseob Yoon, Yujeong Lee, Gi-Yeop Kim, Youngho Kang, Si-Young Choi, Junwoo Son
Summary: A simple strategy to increase electrical conductivity in perovskite oxide semiconductors has been proposed through non-stoichiometry-driven metal exsolution, leading to enhanced carrier concentration in reduced films.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Materials Science, Ceramics
Hiraku Maruyama, Juan C. Nino
Summary: The effects of large thermal gradient annealing on the microstructure of 10 mol% gadolinium doped ceria (GDC) were studied, showing changes in grain orientation, gadolinium diffusion, and enhancement of total conductivity after annealing.
CERAMICS INTERNATIONAL
(2021)
Article
Nanoscience & Nanotechnology
Hanna Bishara, Lena Langenohl, Xuyang Zhou, Baptiste Gault, James P. Best, Gerhard Dehm
Summary: The study focuses on the effect of Fe-alloying on the resistivities of grains and grain boundaries in Cu thin films. Cu films with varying grain sizes and Fe compositions were prepared. The properties, morphology, and compositions of bulk and grain boundaries were analyzed using different methods. Both local electrical measurements and global resistivity characterization were performed to obtain specific resistivities and calculate the grain boundary reflection coefficient. It was found that alloying significantly increased the resistivity of grain boundaries while causing only minor influence on the grain interior.
SCRIPTA MATERIALIA
(2023)
Article
Materials Science, Ceramics
Haowen Liu, Ateer Bao, Jun Zhang, Yaohang Gu, Xiaoyan Zhang, Xiwei Qi
Summary: A new kind of high-entropy rare earth garnet ceramics was successfully synthesized by solid state reaction. The increase of Al content leads to the decrease of relative dielectric constant and the increase of dielectric loss. The activation energies of grain boundary and grain electrical conductivities indicate that the difference between them enhances the dielectric properties. These findings provide important insights for the study of colossal dielectric materials.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Physical
Christoph Riedl, Matthaus Siebenhofer, Andreas Nenning, Gernot Friedbacher, Maximilian Weiss, Christoph Rameshan, Johannes Bernardi, Andreas Limbeck, Markus Kubicek, Alexander Karl Opitz, Juergen Fleig
Summary: The addition of minor amounts of Pt into LSF thin film electrodes has been found to improve their oxygen exchange performance, with even a 5 nm layer of Pt doped LSF showing a 2.5-fold increase in polarization resistance. In situ impedance measurements were conducted to compare the p(O-2) and temperature dependent impedance properties of pure and Pt doped LSF, leading to the conclusion that Pt4+ introduces additional active sites.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Physical
Matthaeus Siebenhofer, Christoph Riedl, Alexander Schmid, Andreas Limbeck, Alexander Karl Opitz, Juergen Fleig, Markus Kubicek
Summary: The oxygen exchange reaction mechanism on pristine surfaces of SOFC cathode materials was investigated using in situ impedance spectroscopy, revealing similar characteristics among materials with moderate ionic conductivity. By controlling defect concentrations through electrode polarization, significantly different activation energies for oxygen incorporation and evolution were determined.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Physical
C. Herzig, J. Frank, A. Nenning, M. Gerstl, A. Bumberger, J. Fleig, A. K. Opitz, A. Limbeck
Summary: The impact of sulfur incorporation into GDC thin films on their in-plane ionic conductivity was investigated, revealing a detrimental effect on grain boundary conductivity. Online-LASIL was employed to quantify the amount of sulfur incorporated into the films, highlighting a potential pathway for sulfur incorporation and ion transport degradation along GDC grain boundaries with oxysulfide formation.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Materials Science, Ceramics
Matthaeus Siebenhofer, Federico Baiutti, Juan de Dios Sirvent, Tobias M. Huber, Alexander Viernstein, Stefan Smetaczek, Christopher Herzig, Maciej Oskar Liedke, Maik Butterling, Andreas Wagner, Eric Hirschmann, Andreas Limbeck, Albert Tarancon, Jurgen Fleig, Markus Kubicek
Summary: The defect chemistry and electronic trapping energies in undoped single crystalline SrTiO3 were investigated using electrochemical impedance spectroscopy and positron annihilation lifetime spectroscopy. The results showed that the chemical capacitance is a valuable tool for establishing a defect model based on electrochemical measurements and analyzing defect concentrations. The chemical capacitance analysis and positron annihilation lifetime spectroscopy are consistent in quantifying the defect concentrations in SrTiO3.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Nanoscience & Nanotechnology
Martin Krammer, Alexander Schmid, Andreas Nenning, Andreas Ewald Bumberger, Matthaeus Siebenhofer, Christopher Herzig, Andreas Limbeck, Christoph Rameshan, Markus Kubicek, Juergen Fleig
Summary: Electrochemical impedance spectroscopy was used to investigate the chemical capacitance of LSC thin-film electrodes under anodic polarization. The study found that the chemical capacitance decreased with increasing anodic overpotentials for both dense electrodes and electrodes with open porosity. However, after annealing in synthetic air or applying high anodic bias voltages, extremely high chemical capacitance peaks were observed. These peaks were attributed to the development of closed pores in the electrodes. Model calculations based on a real-gas equation accurately predicted the experimentally obtained capacitance increase. The analysis of chemical capacitance in solid oxide electrolysis cells can serve as a nondestructive tool to detect and quantify closed porosity.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Electrochemistry
Matthaeus Siebenhofer, Ulrich Haselmann, Andreas Nenning, Gernot Friedbacher, Andreas Ewald Bumberger, Stefan Wurster, Werner Artner, Herbert Hutter, Zaoli Zhang, Juergen Fleig, Markus Kubicek
Summary: The surface morphology and chemistry changes of LSC thin films grown on different substrates were studied under SOFC operation conditions for 100 hours. The formation of particles at the LSC surface was monitored using atomic force microscopy. Different particle formation dynamics were observed depending on the thin film structure. Electron microscopy revealed that the particles were rich in Sr and S. Various measurements were performed on degraded LSC thin films, showing the presence of sulfur on the LSC surface and A-site cation enrichment. Impedance spectroscopy demonstrated an increase in polarization resistance and its activation energy for LSC grown on YSZ over the degradation period.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Nanoscience & Nanotechnology
Christoph Riedl, Matthaeus Siebenhofer, Andreas Nenning, George E. Wilson, John Kilner, Christoph Rameshan, Andreas Limbeck, Alexander K. Opitz, Markus Kubicek, Juergen Fleig
Summary: The oxygen exchange kinetics of Pr0.1Ce0.9O2-delta electrodes were modified by decorating with submonolayer amounts of binary oxides. The OER rate and total conductivity were measured using i-PLD and changes in electrochemical properties were observed after each pulse of surface decoration. The surface chemistry of the electrodes was investigated using NAP-XPS and LEIS. The results showed that the OER rate was significantly altered by the surface decorations, but the fundamental OER mechanism was not affected.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Vedran Vonk, Alexander K. Opitz, Sergey Volkov, Thomas F. Keller, Alexander Hutterer, Pirmin Lakner, Florian Bertram, Ju''rgen Fleig, Andreas Stierle
Summary: Three different platinum oxides were observed during electrochemical potential cycles of platinum thin film model electrodes on yttria-stabilized zirconia at 702 K in air. Electron and atomic microscopy showed delamination and the formation of pyramidlike blisters on the platinum electrode. The identified oxides were an ultrathin PtOx at the buried Pt/YSZ interface, polycrystalline beta-PtO2 inside the blisters, and an ultrathin alpha-PtO2 at the Pt/air interface.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Electrochemistry
Joseph Ring, Lisa Laa, Andreas Limbeck, Vedran Vonk, Sergey Volkov, Andreas Nenning, Juergen Fleig
Summary: In this study, the electrochemical and analytical experiments were conducted to investigate the stability of LLTO with Li-ion-blocking Pt electrodes. It was found that at voltages above 2.5 V, the electrolyte degradation occurred due to the movement of a darkened color front from cathode to anode. The cathode region showed the presence of Ti3+ polarons with high mobility, leading to mixed ion-electron conductivity, while the anode region exhibited a spatially confined, weakly conductive Li depletion zone.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Electrochemistry
Joseph Ring, Andreas Nenning, Juergen Fleig
Summary: LLTO is a promising material in Li ion battery application due to its stable ambient and high ionic conductivity. Under high Li chemical potential, LLTO undergoes a transition from an electrolyte to a high rate capable electrode material. However, the exact voltage of this transition and the electronic conductivity of reduced LLTO were unknown. In this study, we investigated the thermodynamics of lithium insertion and the ion and electron conductivity of reduced LLTO, and proposed a defect chemical model that fits well with the experimental data.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Mattha''us Siebenhofer, Christoph Riedl, Andreas Nenning, Sergej Raznjevic, Felix Fellner, Werner Artner, Zaoli Zhang, Christoph Rameshan, Ju''rgen Fleig, Markus Kubicek
Summary: The oxygen exchange kinetics and surface chemistry of dense LSC thin films on different orientations were investigated using in-situ impedance spectroscopy and NAP-XPS. The results showed that the exchange kinetics on pristine LSC surfaces were fast and independent of orientation. However, in the presence of acidic, gaseous impurities, the (001) orientation was more susceptible to the formation of sulfate adsorbates and performance degradation. This finding has implications for solid oxide cell electrodes with porous materials.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Chemistry, Physical
Matthaeus Siebenhofer, Andreas Nenning, George E. Wilson, John A. Kilner, Christoph Rameshan, Markus Kubicek, Juergen Fleig, Peter Blaha
Summary: This study investigates the effects of sulphur adsorbates and other SOFC poisons on the electronic and ionic properties of an SrO-terminated LSC surface and its oxygen exchange kinetics. Experimental and computational methods were used to analyze the surface modifications caused by the adsorbates. The results show that sulphur adsorbates strongly deactivate the LSC surface and affect oxygen vacancy formation energies. The study also reveals a correlation between work function changes and redistributed charge with the acidity of the adsorbed oxide.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Materials Science, Multidisciplinary
Stefan Smetaczek, Andreas Limbeck, Veronika Zeller, Joseph Ring, Steffen Ganschow, Daniel Rettenwander, Juergen Fleig
Summary: LLZO garnets are potential solid electrolytes for solid-state Li batteries, but suffer from chemical interaction with air and humidity. This study investigates the kinetics of Li+/H+ exchange and its dependence on microstructural features, revealing the importance of microstructure in determining the exchange kinetics of LLZO.
MATERIALS ADVANCES
(2022)
Article
Chemistry, Physical
Christoph Riedl, Matthaeus Siebenhofer, Andreas Nenning, Alexander Schmid, Maximilian Weiss, Christoph Rameshan, Andreas Limbeck, Markus Kubicek, Alexander Karl Opitz, Juergen Fleig
Summary: In this study, mixed conducting cathode materials were characterized for their catalytic performance using in situ impedance spectroscopy. The results showed excellent catalytic properties, with polarization resistances two orders of magnitude lower than previously reported. However, traditional measurement setups often led to contamination by sulfate adsorbates, resulting in increased surface polarization resistances. This study highlights the importance of accurately assessing the catalytic properties of these materials.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Materials Science, Multidisciplinary
Alexander Viernstein, Markus Kubicek, Maximilian Morgenbesser, Tobias M. Huber, Matthaeus Siebenhofer, Juergen Fleig
Summary: UV irradiation significantly affects the conductivity of undoped SrTiO3 single crystals, with opposite effects observed in oxidizing and reducing atmospheres. In N2/O2 atmospheres, UV exposure enhances the conductivity, while in H2 atmosphere, it surprisingly decreases the conductivity. The changes in defect concentrations due to UV-driven oxygen incorporation from the gas phase into the oxide are identified as the main cause of these conductivity changes.
MATERIALS ADVANCES
(2022)
Article
Materials Science, Ceramics
Dan Zhao, Yi Feng, Zhipeng Pi, Fan Zhang
Summary: Phase equilibria in the ZrO2-GdO1.5-TaO2.5 (ZGTO) system were experimentally investigated, and the differences between ZGTO and the existing ZrO2-YO1.5-TaO2.5 (ZYTO) were discussed. The study is useful for thermodynamic assessment of ZGTO and can guide the design of novel thermal barrier coatings materials.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Yutaka Ohya, Wingki Mey Hendra, Chika Takai-Yamashita, Takayuki Ban
Summary: Diffusion couples of rutile and corundum single crystals were prepared and examined to study the solid solution and precipitation of corundum in rutile during cooling. Different precipitation forms of corundum were observed under different cooling conditions.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Jiaming Zhan, Yunfa Guo, Hao Wang
Summary: This study systematically investigates the mechanical behaviors of calcium fluoride in humid environments. The effects of water on the deformation and plastic enhancement of CaF2 under indentation are explored through microindentation experiments, atomic simulations, and Raman spectroscopy measurement.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Hangfeng Zhang, Henry Giddens, Theo Graves Saunders, Matteo Palma, Isaac Abrahams, Haixue Yan, Yang Hao
Summary: The relationship between low and high frequency tunabilities in tin substituted barium titanate ceramics was investigated. It was found that there are differences in tunabilities at different frequencies due to the different activities of larger ferroelectric domains and polar nanoclusters.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Kaibiao Xi, Jiacheng Liu, Beibei Song, Huarong Cheng, Yihao Li, Xiaole Yu, Mupeng Zheng, Mankang Zhu, Yudong Hou
Summary: Composite modulation in the superparaelectric state of the BTBZ-CT system is proposed as an effective strategy to achieve both NTCC and excellent energy storage performance in dielectric ceramics. The addition of BZ and CT to BT ferroelectrics can move the SPE state to the normal use temperature zone, resulting in enhanced NTCC characteristics and energy storage performance. Furthermore, intentional precipitation of CT at grain boundaries can refine the grain size, increase the bandgap, and strengthen the local electric field distribution, thereby enhancing the breakdown electric field.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Hamed Salimkhani, Lovro Fulanovic, Till Froemling
Summary: The demand for robust multilayer ceramic capacitors with high-temperature and high-power capabilities is increasing rapidly. However, cost-effective production is a challenge. This study investigates the use of Na0.5Bi0.5TiO3-based materials as promising lead-free options. By adding sintering aids, the sintering temperature of Na0.5Bi0.5TiO3-BaTiO3-CaZrO3-BiAlO3 solid solutions was successfully reduced to 975 degrees C, suitable for co-sintering with Cu electrodes without adverse effects on capacitor properties.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Mingxing Li, Ran Mo, Zeshui Xu, Jie Zhou, Conglin Zhang, Xuefeng Cui, Fang Ye, Laifei Cheng, Ralf Riedel
Summary: Polymer infiltration and pyrolysis is an effective method for preparing ceramic matrix composites. The transformation of polymer to ceramic during the process affects the residual stress and interface behavior in the composites.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Yan Kang, Lin Chen, Chang-Jiu Li, Guan-Jun Yang
Summary: A novel abradable seal coating with low hardness and high bonding strength was successfully designed and prepared. This coating has significantly higher abradability and erosion resistance compared to metal-based coatings, and can retain excellent abradability and have a long lifetime during service.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Qingzhong Song, Xiangdong Zha, Ming Gao, Yingche Ma
Summary: This study analyzes the influence of calcia refractory purity on the properties of calcia crucibles. Higher purity calcia results in well-developed grains and improved hydration resistance, leading to better high-temperature strength and thermal shock resistance. In contrast, lower purity calcia crucibles exhibit inferior properties. Therefore, high-purity calcia is considered a potential refractory for manufacturing oxide crucibles.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Sehreish Abrar, Faisal Nazeer, Zhuang Ma, Ling Liu, Abdul Malik, Mustafa Kamal, Abdullah G. Al-Sehemi
Summary: To raise the operating temperature of Si-based ceramic matrix composites (CMCs), researchers have applied thermal/environmental barrier coating (T/EBCs) materials, typically rare earth silicates. However, the high thermal conductivity and the mismatch of thermal expansion have been major challenges in developing new materials that can offer thermal insulation and environmental protection to CMCs. In this study, entropy engineering was used to create a multicomponent equi-atomic single-phase pyro silicate with extremely low thermal conductivity and enhanced water vapor corrosion resistance. The research findings show the potential of high entropy disilicates in achieving ultra-low thermal conductivity and low weight loss in corrosive environments.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Zi-bo Niu, Daxin Li, Dechang Jia, Zhihua Yang, Kunpeng Lin, Paolo Colombo, Ralf Riedel, Yu Zhou
Summary: In this study, SiBCN ceramics with a special structure were prepared to improve the oxidation resistance. The effect of the structure on oxidation behavior and kinetics was investigated, revealing that the special structure can effectively inhibit heterogeneous oxidation and enhance the oxide layer composition.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Melike Donmez, Metehan Erdogan, Cihangir Duran
Summary: The limited densification of CeO2 ceramics was improved by using an anorthite-based glass, resulting in high dielectric constant and quality factor with minimum dielectric loss. The CeO2-(anorthite-based) glass ceramic showed promising results in terms of low temperature densification and microwave properties.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
S. Rahmati, R. G. A. Veiga, J. Mostaghimi, T. Coyle, A. Dolatabadi
Summary: This study provides an atomic-scale description of the high-velocity impact of alpha-Al2O3 particles onto an alpha-Al2O3 substrate during Aerosol Deposition (AD). The results suggest that the crystal orientation plays a crucial role in both plasticity and damage of the nanoparticles. Impact velocity has a direct correlation with plasticity and fragmentation, but adhesion efficiency has only a marginal increase. The crucial element lies in the substrate's surface alterations caused by the fragments left on the substrate after impact.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Bo-Wen Chen, Yan-Mei Kan, De-Wei Ni, Chun-Jing Liao, Hong-Da Wang, Yu-Sheng Ding, Shao-Ming Dong
Summary: This study characterized the long-term and repeated ablation properties of modified Cf/HfC-SiC composites with YB4-Al2O3-Si3N4 under an air plasma torch. The structural stability and viscosity of the oxide layer were found to affect the ablation resistance of the composites. By forming nano c-HfO2 grains and high-viscosity Al-Si-Y-O glassy phase, the structural stability of the oxide layer was improved, resulting in enhanced ablation resistance. However, the oxidation of Si3N4 led to the formation of NO, NO2, and excessive SiO2 glassy phase, which resulted in a porous structure and reduced the viscosity of the oxide layer. Therefore, the addition of Si3N4 decreased the ablation resistance of the composites.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
Article
Materials Science, Ceramics
Yongxing Wei, Huawei Zhang, Siyuan Dong, Changqing Jin, Chenxing Bai, Junle Dai, Zengzhe Xi, Zhonghua Dai, Zengyun Jian, Li Jin
Summary: In this study, solid solutions of xBi(Ni1/2Hf1/2)O-3-(1 - x)PbTiO3 (xBNH-PT) were synthesized to investigate their phase boundary behaviors and physical properties. The presence of a tetragonal-pseudocubic phase boundary and a spontaneous ferroelectric-relaxor transition at specific compositions were confirmed. The introduction of a tetragonal-pseudocubic phase boundary improved the piezoelectric properties and suppressed the spontaneous ferroelectric-relaxor transition.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2024)
