Article
Materials Science, Ceramics
Yuqi Liang, Bingcheng Luo, Huijuan Dong, Danyang Wang
Summary: The study reported the electronic structure and charge transport properties of high-entropy oxide Ba(Zr0.2Sn0.2Ti0.2Hf0.2Nb0.2)O3 annealed at different temperatures. It was found that the band gap narrowed with increasing annealing temperature and all thin films exhibited semiconductor-like behavior. Two charge transport mechanisms were identified through analysis methods.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Physical
Xinjie Wang, Yi-Chi Wang, Biaolin Peng, Jianyu Deng, Ya Yang, Wenhong Sun, Zhonglin Wang
Summary: This paper investigates the influence of thickness on the performance of ferroelectric thin films and reveals that thicker films enhance spontaneous polarization but decrease dielectric permittivity, coercivity field, residual polarization, efficiency, and energy density, and gradually transition the positive electrocaloric effect into a negative regime. These changes can be attributed to the variation of in-plane tensile stresses with thickness, resulting in an increase in the tetragonal phase and a decrease in the rhombohedral phase structure.
Article
Materials Science, Ceramics
Zhuang Lin, Ben Ma, Zhaohui Chen, Yingke Zhou
Summary: Commercial use of solid oxide fuel cells (SOFCs) requires high output performance and excellent long-term stability. In this study, a nanostructured spinel high-entropy oxide (Fe0.2Mn0.2Co0.2Ni0.2Zn0.2)3O4 (FMCNZ) was developed as the SOFC cathode using an impregnation method. The FMCNZ cathode showed higher oxygen reduction reaction (ORR) performance compared to traditional spinel cathodes, attributed to the diversity of surface metal cations and the increase of surface oxygen vacancies brought on by the high entropy design. The nanostructured FMCNZ cathode exhibited stable performance after 100 hours of cell operation, providing a promising path for developing high-performance cathodes.
CERAMICS INTERNATIONAL
(2023)
Article
Materials Science, Ceramics
Emmanuel I. I. I. Ricohermoso, Florian Klug, Helmut Schlaak, Ralf Riedel, Emanuel Ionescu
Summary: This study focuses on the preparation and characterization of silicon oxycarbide thin films, optimizing the deposition process using the Taguchi method. It was found that increasing carbon content is beneficial for crack-free film preparation and resulting ceramic films have higher electrical conductivity, suitable for use in miniaturized piezoresistive strain gauges.
INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY
(2022)
Article
Materials Science, Ceramics
Su Yeon Cha, Dongwoo Kim, Hojoon Lim, Bongjin Simon Mun, Do Young Noh, Hyon Chol Kang
Summary: The study focused on the synthesis and characterization of non-stoichiometric Ga2O3-x thin films deposited on sapphire substrates using radio-frequency powder sputtering. The thin films were found to have electronic states mainly consisting of Ga3+ and Ga1+, exhibiting semiconductor electrical characteristics.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
C. Guillen, J. Herrero
Summary: Tungsten oxides with versatile optoelectronic characteristics can be obtained through reactive DC sputtering, allowing for control of intrinsic defects, sub-bandgap absorption, and carrier density. Tuning these properties is crucial for various applications of tungsten oxide thin films.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Ceramics
Yanli Wang, Hongyi Li, Huijun Liu, Lingxu Yang, Chaoliu Zeng
Summary: Two Cr-free high entropy oxides, an equimolar (MnFeCoNiCu)3O4 and a non-equimolar (Mn0.272Fe0.272Co0.272Ni0.092Cu0.092)3O4, were synthesized using a solid-state reaction method. The reaction sequence and electrical conductivity of these two oxides were studied. A rock-salt phase containing a solid solution of NiO and CuO was observed in the synthesis process of (MnFeCoNiCu)3O4, while (Mn0.272Fe0.272Co0.272Ni0.092Cu0.092)3O4 exhibited a single spinel phase (Fd-3m) at a lower temperature. The electrical conductivity of (Mn0.272Fe0.272Co0.272Ni0.092Cu0.092)3O4 was approximately three times higher than that of (MnFeCoNiCu)3O4.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Physical
Cecilia Guillen
Summary: Tungsten oxide thin films have versatile semiconductor properties that are dependent on oxygen content and crystalline state. Oxygen vacancies create new absorption bands, resulting in colored films. Crystal structure disorders affect electrical and optical characteristics.
Article
Nanoscience & Nanotechnology
Lvkang Shen, Yang Zhang, Tianyu Liu, He Wang, Chunrui Ma, Ming Liu
Summary: Magnetoresistance-based devices have attracted attention due to their ability to use spins as information carriers. However, these devices face challenges such as limited magnetoresistance ratios, low work temperature, or high magnetic field. This study introduces a flexible bending-controlled magneto-resistance device based on the La0.67Ba0.33MnO3 film, achieving high magnetoresistive performance and suggesting possible applications such as tunable multistage switches.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Antoine Raison, Nathalie Prud'homme, Wu Wang, Diana Dragoe, Nita Dragoe
Summary: We have successfully synthesized a multi-cationic oxide (MgCoNiCuZn)O through pulsed liquid injection chemical vapor deposition. The synthesis was carried out at temperatures ranging from 400 degrees C to 550 degrees C, using five metal-organic precursors solubilized in dimethoxyethane (DME). The microstructure of the material was analyzed using HRTEM with HAADF, SEM, EDS, XPS, and XRD techniques before and after annealing.
Article
Materials Science, Ceramics
Yufeng Liu, Jiadong Hou, Chufei Cheng, Fuhao Cheng, Teng Su, Yang Miao, Chao Ma, Xiaomin Wang
Summary: A series of high entropy oxides (HEOSs) with non-isomolar ratios of perovskite structures were successfully prepared by ball milling and high-temperature sintering. The resulting Sr(Ti0.2Zr0.2Zn0.2Sn0.2Hf0.2)O3-sigma exhibited single-phase formation and uniform element distribution. The orthorhombic Pbnm perovskite structure was observed in the TEM analysis. The highest electrical conductivity (2.41 x 10-3 S/cm) and lowest activation energy (Ea = 0.57 eV) were achieved by Sr(Ti0.28Zr0.18Zn0.18Sn0.18Hf0.18)O3-sigma due to lattice distortion and oxygen vacancy concentration.
CERAMICS INTERNATIONAL
(2023)
Article
Nanoscience & Nanotechnology
Xueyang Mu, Weike Wang, Chongcai Sun, Dan Zhao, Chuang Ma, Jiankang Zhu, Mato Knez
Summary: In this study, the electronic properties of organic-inorganic hybrid semiconducting polymers were altered and characterized through in situ controlled vapor phase infiltration (VPI) of metal precursors. The doped thin films showed significantly improved electrical conductivity and excellent environmental stability.
Article
Materials Science, Multidisciplinary
Weixuan Liang, Jiaxing Huang, Zejun Wang, Ciyuan Huang, Qi Wei, Chenghui Liao, Ruijie Ma, Tao Liu, Weiya Zhu, Yuan Li
Summary: In this work, modified PEDOT: PSS materials (PEDOT: PSS-BA, PEDOT: PSS-HA, and PEDOT: PSS-OA) were prepared by doping alkyl diamines into PEDOT: PSS, resulting in enhanced conductivity due to more ordered molecular packing. Among these modified products, the OSC devices based on PEDOT: PSS-BA demonstrated a superior power conversion efficiency of 18.44%, which is one of the highest values in binary OSCs.
ACS MATERIALS LETTERS
(2023)
Article
Chemistry, Physical
N. Jhansi, D. Balasubramanian, Jih-Hsing Chang, K. Mohanraj, R. Marnadu, M. Aslam Manthrammel, Mohd Shkir
Summary: The jet nebulizer spray pyrolysis method is used to grow CuO thin films at different substrate temperatures, and the results show the strong influence of substrate temperature on the properties of the films, such as crystallite size, bandgap, and electrical conductivity.
Article
Materials Science, Multidisciplinary
Hei Man Yau, Xinxin Chen, Chi Man Wong, Deyang Chen, Jiyan Dai
Summary: By using X-ray diffraction and Transmission Electron Microscope, researchers revealed the epitaxial growth of Al-doped HfO2 thin films on differently oriented SrTiO3 substrates, showing various phase structures and ferroelectric properties. The film grown on (111) SrTiO3 substrate exhibited the largest electromechanical effect, indicating the orientation control of phase transitions and ferroelectricity in Al-doped HfO2 thin films.
MATERIALS CHARACTERIZATION
(2021)
Article
Chemistry, Physical
Andriy Zakutayev, Sage R. Bauers, Stephan Lany
Summary: This article discusses the progress in experimental synthesis of theoretically predicted multivalent ternary nitrides, with a focus on zinc and magnesium-based materials. Through thin film and bulk experiments, several predicted multivalent ternary nitride compounds have been successfully synthesized.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Piero Mazzolini, Zsolt Fogarassy, Antonella Parisini, Francesco Mezzadri, David Diercks, Matteo Bosi, Luca Seravalli, Anna Sacchi, Giulia Spaggiari, Danilo Bersani, Oliver Bierwagen, Benjamin Moritz Janzen, Marcella Naomi Marggraf, Markus R. Wagner, Ildiko Cora, Bela Pecz, Abbes Tahraoui, Alessio Bosio, Carmine Borelli, Stefano Leone, Roberto Fornari
Summary: Unintentionally doped kappa-Ga2O3 epitaxial films on sapphire substrates exhibit columnar rotational domains that inhibit in-plane electronic conduction. The introduction of silane doping increases the domain size and mobility, improving in-plane conduction. Non-destructive techniques based on X-ray diffraction and Raman spectroscopy can be used to compare domain dimensions.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Andrea Crovetto, Thomas Unold, Andriy Zakutayev
Summary: Through thin-film experiments, electronic structure calculations, and semiclassical Boltzmann transport theory, we find that Cu3P is an intrinsic semimetal, while experimentally realizable Cu3-xP films are p-type semimetals due to copper vacancy doping. Small-sized Cu3-xP samples may become semiconductors as a result of quantum confinement effects. This study demonstrates the suitability of reactive sputter deposition for detailed high-throughput studies of emerging metal phosphides.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Meagan C. C. Papac, Jake Huang, Andriy Zakutayev, Ryan O'Hayre
Summary: Through combinatorial experimental methods and multidimensional Bayesian analysis, the dependency of triple ionic-electronic conducting oxides (TIECs) on chemical composition and environmental conditions in high-temperature electrochemical applications is investigated. The study reveals that Co-rich compositions achieve the lowest overall polarization resistance, while Fe substitution may increase polarization resistance. This work provides a map of electronic properties of TIEC materials under relevant conditions, and demonstrates a unique approach to studying TIECs combining combinatorial experiments and Bayesian analysis.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Electrochemistry
Jake Huang, Neal P. Sullivan, Andriy Zakutayev, Ryan O'Hayre
Summary: The distribution of relaxation times (DRT) is a versatile method for analyzing electrochemical impedance spectroscopy (EIS) data from complex devices. It does not require a generative model, making it useful when the system's governing principles are not fully understood. However, DRT estimation is an ill-posed problem that relies on subjective choices of regularization and tuning, leading to the risk of misleading interpretations of the data.
ELECTROCHIMICA ACTA
(2023)
Article
Chemistry, Physical
Mirjana Dimitrievska, Alexander P. Litvinchuk, Andriy Zakutayev, Andrea Crovetto
Summary: In this work, a reference Raman spectrum of CuP2 was provided, and all Raman active modes were analyzed from both experimental and theoretical perspectives. The phonon density of states and phonon dispersions were also calculated, providing a microscopic understanding of the phonon lines. The agreement between the experimental and DFT-calculated Raman spectra of CuP2 was found, which can be used as a reference for future investigations on this material.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Hanzhe Liu, Jonathan M. Michelsen, Jocelyn L. Mendes, Isabel M. Klein, Sage R. Bauers, Jake M. Evans, Andriy Zakutayev, Scott K. Cushing
Summary: Transient extreme ultraviolet (XUV) spectroscopy has the ability to separate photoexcited electron and hole dynamics with element specificity, making it a valuable tool for characterizing solar energy materials. In this study, surface-sensitive femtosecond XUV reflection spectroscopy is used to measure the dynamics of photoexcited electron, hole, and band gap in ZnTe, a promising photocathode for CO2 reduction. By developing an ab initio theoretical framework, the complex transient XUV spectra are assigned to the electronic states of the material, allowing the identification of relaxation pathways and quantification of their time scales in photoexcited ZnTe.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Davi M. M. Febba, Kevin R. R. Talley, Kendal Johnson, Stephen Schaefer, Sage R. R. Bauers, John S. S. Mangum, Rebecca W. W. Smaha, Andriy Zakutayev
Summary: We report the design and implementation of an autonomous workflow for sputter deposition of thin films with controlled composition. By minimizing the absolute error between desired and measured optical emission signals, we demonstrate the reliability of this method in synthesizing thin films with specific compositions.
Article
Energy & Fuels
Fan Liu, Hao Deng, David Diercks, Praveen Kumar, Mohammed Hussain Abdul Jabbar, Cenk Gumeci, Yoshihisa Furuya, Nilesh Dale, Takanori Oku, Masahiro Usuda, Pejman Kazempoor, Liyang Fang, Di Chen, Bin Liu, Chuancheng Duan
Summary: A simple and scalable approach for fabricating ultrathin and robust proton-conducting electrolytes is reported. The composites formed in situ significantly reduce the resistances and enable high power densities and current densities in fuel-cell mode and steam electrolysis mode, respectively.
Article
Materials Science, Multidisciplinary
Christopher L. Rom, Rebecca W. Smaha, Callan A. Knebel, Karen N. Heinselman, James R. Neilson, Sage R. Bauers, Andriy Zakutayev
Summary: Solid state synthesis of nitride materials can lead to different crystal structures compared to thin film synthesis. This study explores the chemical phase space of Mg-W-N using rapid thermal annealing, revealing new phases and demonstrating how polymorphic transformations can be controlled using this method.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Keisuke Yazawa, John Hayden, Jon-Paul Maria, Wanlin Zhu, Susan Trolier-McKinstry, Andriy Zakutayev, Geoff L. Brennecka
Summary: This article describes and explains the anomalous polarization reversal behavior of wurtzite-structured nitride thin film ferroelectrics Al0.7Sc0.3N and Al0.94B0.06N under high electric fields and proposes a general model that can be applied to other nucleation and growth transitions. The work provides a more comprehensive description of nucleation and growth kinetics applicable to any system and specifically addresses the abrupt polarization reversal behavior in new wurtzite-structured ferroelectrics through two related but distinct scenarios.
MATERIALS HORIZONS
(2023)
Article
Materials Science, Multidisciplinary
Daniel R. Clark, David R. Diercks, Sandrine Ricote, Tania Tauer Dearden, Neal P. Sullivan, J. Will Medlin, Brian P. Gorman, Ryan P. O'Hayre
Summary: This study characterizes the grain boundary (GB) chemistry of BZY10 samples prepared by four different methods using laser-pulsed atom probe tomography (APT). Oxygen depletion and varying segregation/depletion behaviors of cation constituents were observed at the GBs. Common impurities such as Al, Fe, Mg, Si, and Sr were also found to accumulate at the GBs. The study reveals the complexity of BZY10 GB chemistry and the unexpected differences in GB chemistry between adjacent boundaries.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Physical
Rachel Woods-Robinson, Kristin A. Persson, Andriy Zakutayev
Summary: This study investigates the phase space of barium tin sulfide (Ba-Sn-S) using experimental and theoretical methods, exploring phase behavior, electronic properties, and optical absorption properties. The findings highlight the potential of Ba-Sn-S materials for solar energy harvesting and semiconductor applications.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Physical
Liyang Fang, Fan Liu, David Diercks, Praveen Kumar, Feng Zhao, Dong Ding, Chuancheng Duan
Summary: Solid oxide electrochemical cells (SOECs) are a promising clean energy technology that can efficiently convert energy stored in fuels. The current SOECs suffer from poor performance, but this study successfully designed a new oxygen electrode material with enhanced electrocatalytic activity, achieving exceptional power generation performance and stability.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Physical
Liyang Fang, Fan Liu, David Diercks, Praveen Kumar, Feng Zhao, Dong Ding, Chuancheng Duan
Summary: Solid oxide electrochemical cells (SOECs) are a highly promising clean energy technology that can efficiently convert chemical energy to electricity and produce chemicals from abundant resources. However, the current SOECs suffer from poor performance. In this study, a hybrid oxygen electrode material was designed, which significantly improved the electrocatalytic activities of the oxygen reduction and evolution reactions. The newly developed SOECs achieved exceptional performance for power generation and steam electrolysis, with high stability.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
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)