Acta Materialia最新文献

{"title":"Ab initio study of doping effects on the ferroelectric and piezoelectric properties of ZrO₂","authors":"Alexandre Silva ,&nbsp;Richard Ganser ,&nbsp;José P.B. Silva ,&nbsp;Alfred Kersch ,&nbsp;Veniero Lenzi ,&nbsp;Luís Marques","doi":"10.1016/j.actamat.2025.121584","DOIUrl":"10.1016/j.actamat.2025.121584","url":null,"abstract":"<div><div>Ferroelectric binary oxides show great promise for application in energy storage, non-volatile memories, and neuromorphic computing devices. Compared to hafnia (HfO₂), zirconia (ZrO₂) thin films have been understudied in spite of significant recent progress. Doping has emerged as a promising tool to tune the ferroelectric properties of HfO₂ and Hf_xZr_1-xO₂ (HZO). However, an extensive study of the effects of doping on the structural and ferroelectric properties of ZrO₂ is still widely missing. In this study, through density functional theory (DFT) and ab initio molecular dynamics (AIMD) calculations we investigate the effects of B, Si, Al, Mg, Sc, Ca, Ce, Ta, Hf, Y, Sr, La, Ba and Rb doping on the structural distortions, relative phase stability, phase transition temperatures, spontaneous polarization and piezoelectric response of the monoclinic (m-), polar orthorhombic (o-) and tetragonal (<em>t-</em>) phases of ZrO₂ at 3.125 and 6.25 cat. % doping concentration. We demonstrate that the spontaneous polarization magnitude in ZrO₂ can be significantly enhanced through doping with Si, B, and Al. In addition, our results reveal that the relative phase stability and phase transition temperatures of ZrO₂ can be tuned by doping. Specifically, our calculations confirm that Si doping promotes the stabilization of the t-phase in ZrO₂. Furthermore, we show that doping shifts the phase transition temperature, leading to substantial improvements in piezoelectric response, with up to a sevenfold increase observed in Al-doped ZrO₂. Consequently, this work highlights the most promising dopants capable of enhancing the ferroelectric and piezoelectric properties of ZrO₂ thin films.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"301 ","pages":"Article 121584"},"PeriodicalIF":9.3,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145140680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stabilizing nanocrystals via interface co-segregation and clustering","authors":"Y.J. Wang ,&nbsp;Y. Yuan ,&nbsp;W.H. Ji ,&nbsp;Y. Wu ,&nbsp;H. Wang ,&nbsp;X.J. Liu ,&nbsp;S.H. Jiang ,&nbsp;X.B. Zhang ,&nbsp;H.H. Wu ,&nbsp;Y.J. Zhang ,&nbsp;X.Y. Yuan ,&nbsp;H.H. Zhu ,&nbsp;T.G. Langdon ,&nbsp;Y. Huang ,&nbsp;L. Gu ,&nbsp;Q.H. Zhang ,&nbsp;X.D. Xu ,&nbsp;B. Gault ,&nbsp;D. Raabe ,&nbsp;Z.P. Lu","doi":"10.1016/j.actamat.2025.121589","DOIUrl":"10.1016/j.actamat.2025.121589","url":null,"abstract":"<div><div>Nanocrystalline (NC) metals are generally metastable and prone to undergo grain coarsening, which severely impedes their engineering application. A strategy to counteract this phenomenon lies in decreasing the energetic driving force for grain growth, through grain boundary segregation. The natural thought of ‘more segregation is better’, which was exercised over decades to solve this problem, however, does not work because interfaces have only limited solute decoration tolerance. Herein, we propose to solve this long-standing problem by doping with multiple solutes, which creates a synergistic combination of thermodynamic and kinetic stabilization mechanisms without inducing formation of new phases. This is enabled by introducing chemical compositional complexity to GBs, which possibly allows more efficient GB stabilization through segregation, thus drastically reducing alloying costs while retain the original properties of the NCs. We applied this new design approach to NC-Nb and show that we can increase its instability temperature from 873 to 1173 K with as little alloying as only 2 at.% of Co, Ni, Ti and Hf with equal fractions. The material maintains its nanocrystalline structure after annealing at 1173 K for 50 h. Therefore, this work presents a promising design strategy for developing stable dilute NC materials for advanced engineering application.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"301 ","pages":"Article 121589"},"PeriodicalIF":9.3,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145140716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Creating Gallium-based alloys with the lowest melting point via reverse design approach","authors":"Yanmiao Wu ,&nbsp;Taiang Liu ,&nbsp;Tian Lu ,&nbsp;Minjie Li ,&nbsp;Wenyan Zhou ,&nbsp;Wencong Lu","doi":"10.1016/j.actamat.2025.121586","DOIUrl":"10.1016/j.actamat.2025.121586","url":null,"abstract":"<div><div>Gallium-based low-melting-point alloys, also known as gallium-based liquid metals, are widely used across various fields due to their excellent convective properties. However, their phase transition and volume expansion during freezing may present safety risks, which highlights the need for alloys with even lower melting points for enhanced adaptability in low-temperature environments. In this study, we introduce an active learning-based reverse design framework to accurately identify gallium-based alloys with reduced melting points. Through two rounds of iteration, we successfully designed and synthesized Ga_60.40In_22.49Sn_15.60Zn_1.51 and Ga_59.33In_24.74Sn_14.51Zn_1.42, with melting points of 6.80 °C and 6.85 °C, which surpassed the lowest record of 8 °C reported. These findings demonstrate that this active learning-based reverse design method can significantly accelerate the development of low-melting-point alloys and offer valuable insights for the reverse design of other materials.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"301 ","pages":"Article 121586"},"PeriodicalIF":9.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145140718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Percolation theory for short-range correlated three-dimensional topologies","authors":"Aayushi Chauhan ,&nbsp;Christopher A. Schuh","doi":"10.1016/j.actamat.2025.121583","DOIUrl":"10.1016/j.actamat.2025.121583","url":null,"abstract":"<div><div>Percolation theory can completely describe structure-property relations in random materials if local short-range correlations on the percolation threshold are accounted for. The present work maps the structural space of random binary composites with arbitrary short-range correlations for two topologies - body-centered cubic and face-centered cubic - and finds the variation of percolation threshold over the mapped correlation spaces. Phase inversion symmetry is verified for all states of short-range order, giving an expression for the percolation thresholds where either one of the two constituent phases percolate, and delineating the structures in which both phases form spanning clusters simultaneously. The scaling of percolation properties is also analyzed relative to the percolation phase boundary, and found invariant when short-range order is properly accounted for. Thus, if the phase fraction and short-range order are known, the full geometrical properties of the material are fully known, including the statistical distribution of cluster sizes of both phases and the strength of the percolating cluster.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"301 ","pages":"Article 121583"},"PeriodicalIF":9.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adiabatic demagnetization refrigeration to mK temperatures in NaGdGeO4 crystal","authors":"Zuhua Chen ,&nbsp;Xinyang Liu ,&nbsp;Jun Shen ,&nbsp;Dunhui Wang ,&nbsp;Guochun Zhang ,&nbsp;Lei Xi ,&nbsp;Xiansong Liu ,&nbsp;Xucai Kan ,&nbsp;Changkun Wang ,&nbsp;Yicai Zhang ,&nbsp;Jiahao Gao ,&nbsp;Yanan Zhao ,&nbsp;Zhenxing Li ,&nbsp;Junsen Xiang ,&nbsp;Wei Li ,&nbsp;Heng Tu","doi":"10.1016/j.actamat.2025.121585","DOIUrl":"10.1016/j.actamat.2025.121585","url":null,"abstract":"<div><div>Adiabatic demagnetization refrigeration (ADR) technology is regarded as an effective, easy and sustainable method to replace evaporation or dilution cooling of ³He/⁴He. In practical applications, it is important for magnetic refrigeration materials to possess excellent magnetocaloric effect (MCE) under a small applied field, which is advantageous to further simplifying design and reducing costs. In this article, the centimeter-scaled crystal of NaGdGeO₄ is grown by top seed crystal method. The magnetic performance and MCE of NaGdGeO₄ compound are investigated. NaGdGeO₄ exhibits a low phase transition temperature of 0.7 K, indicating its potential as an ultra-low temperature magnetic refrigerant. Large magnetic entropy changes of 16.7 and 34.5 J·kg^-1·K^-1 are obtained under small field changes of 1 and 2 T at 0.8 and 1.2 K, respectively, which is almost 2 times larger than that of commercial magnetic refrigerant Gd₃Ga₅O₁₂ under the same conditions. For the measurement of quasi-ADR, when initial conditions are <em>μ</em>₀<em>H</em>=6 T, <em>T</em> = 2 K, the temperature trace of non-oriented crystal and powder samples passe a minimum value of 132.5 mK and 157.9 mK, respectively. These outstanding performances suggest that NaGdGeO₄ is a promising candidate for ultra-low temperature magnetic refrigeration applications.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"301 ","pages":"Article 121585"},"PeriodicalIF":9.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145140717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Construction of large-area nanoscale hierarchic topological domains","authors":"Luyong Zhang ,&nbsp;Yuanwei Sun ,&nbsp;Dongfeng Zheng ,&nbsp;Xiangping Zhang ,&nbsp;Mei Wu ,&nbsp;Chao Chen ,&nbsp;Zhen Fan ,&nbsp;Zhipeng Hou ,&nbsp;Deyang Chen ,&nbsp;Guo Tian ,&nbsp;Changjian Li ,&nbsp;Peng Gao ,&nbsp;Jun-Ming Liu ,&nbsp;Xingsen Gao","doi":"10.1016/j.actamat.2025.121577","DOIUrl":"10.1016/j.actamat.2025.121577","url":null,"abstract":"<div><div>The coupling structure that integrates both hierarchical super-structures and polar topology is anticipated to generate exceptional performance characteristics due to their synergic effect. However, fabricating large-area arrays of stable hierarchical center-type topologies at the nanoscale remains a considerable challenge. Here, by employing a unique interfacial build-in field mechanism, we achieved a breakthrough in the large-scale synthesis of stable hierarchic center-type patterns derived from dimensionally confined topologically trivial PbTiO₃ (PTO) <em>a</em>₁/<em>a</em>₂ superdomains. Through nanoscale piezoresponse force microscopy (PFM) and scanning transmission electron microscopy (STEM), the fine domain structures can be clearly delineated, exhibiting distinct four-quadrant textures with charged domain walls appearing at quadrant boundaries, alone with high piezoresponse <em>a</em>/<em>c</em> domains in the central regions. These hierarchic center-type configurations are spontaneously formed and remain stable over several months. Specifically, these domains can also be modulated by either external field or variation nanoislands height, while can be recovered by heating at elevated temperature. These findings provide unique insights into the formation mechanism of hierarchic topological structures and open up potential applications in nano-electromechanical systems, piezotronics, and topological electronics.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"301 ","pages":"Article 121577"},"PeriodicalIF":9.3,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145127855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dislocation core structure from diffuse scattering below the Bragg peaks","authors":"Tamás Ungár ,&nbsp;Gábor Ribárik ,&nbsp;Li Li","doi":"10.1016/j.actamat.2025.121560","DOIUrl":"10.1016/j.actamat.2025.121560","url":null,"abstract":"<div><div>The characteristics and dimensions of dislocation cores remain a fundamental inquiry in the field of plasticity. Molecular dynamics simulations, along with the regularization of singularities in continuum approaches, can provide valuable insights into core configurations. However, experimental evidence is limited and frequently indirect. In this study, diffuse scattering observed below the Bragg peaks, resulting from narrow distorted core regions, is employed to ascertain the widths of dislocation cores in a highly dislocated Ni-18 wt.%Fe nanocrystalline alloy. High-resolution synchrotron X-ray diffraction patterns are analysed to determine dislocation densities, crystallite sizes, and planar defect densities utilizing the Convolutional Multiple Whole Profile line profile analysis technique. A model addressing diffuse scattering from dislocation core material, in conjunction with a cumulative assessment of diffuse scattering associated with thermal diffuse scattering and short-range order, is integrated into the line profile analysis framework. This enhanced method also addresses the singularity at short distances in the Krivoglaz-Wilkens strain function, thereby mitigating the risk of overestimating dislocation densities. The findings indicate that the dislocation core width in the present alloy is approximately 6.7(±0.3) times the Burgers vector length, which aligns well with molecular dynamics simulations and continuum mechanical calculations.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"301 ","pages":"Article 121560"},"PeriodicalIF":9.3,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145263092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Asymmetrical defect sink behavior of HCP/BCC Zr/Nb multilayer interfaces: Bubble-denuded zones at Nb layers","authors":"N. Daghbouj ,&nbsp;H.S. Sen ,&nbsp;M. Bensalem ,&nbsp;J. Duchoň ,&nbsp;B. Li ,&nbsp;M. Karlík ,&nbsp;F. Ge ,&nbsp;V. Krsjak ,&nbsp;P. Bábor ,&nbsp;M.O. Liedke ,&nbsp;M. Butterling ,&nbsp;A. Wagner ,&nbsp;B. Karasulu ,&nbsp;T. Polcar","doi":"10.1016/j.actamat.2025.121579","DOIUrl":"10.1016/j.actamat.2025.121579","url":null,"abstract":"<div><div>Radiation-induced helium (He) bubble formation poses a major challenge to the structural integrity of materials in nuclear energy systems. In this study, we investigate defect evolution and He behavior in Zr/Nb nanoscale metallic multilayers (NMMs) with immiscible BCC/HCP interfaces, irradiated with 80 keV He ions at fluences ranging from 1 × 10¹⁶ to 1 × 10¹⁷ He/cm². For comparison, single-crystal Nb and polycrystalline Zr were also irradiated under identical conditions to serve as reference materials. Using cross-sectional TEM, SIMS, STEM-EELS, nanoindentation, Doppler Broadening Positron Annihilation Spectroscopy (DBPAS), Positron Annihilation Lifetime Spectroscopy (PALS), and atomistic simulations (DFT and MD), we reveal a highly asymmetric damage response across the multilayer interfaces. Zr layers exhibit larger He bubbles (1.5–2.8 nm), higher swelling (∼1.2%), and greater helium retention, while Nb layers develop bubble-denuded zones (BDZs) exclusively around the interfaces, where bubble nucleation is strongly suppressed and swelling is limited to ∼0.4%. This asymmetry arises from differences in atomic transport properties: DFT calculations show lower migration barriers for vacancies and He atoms in Nb (0.4 and 0.19 eV, respectively), enabling efficient defect migration and recombination at interfaces, whereas Zr retains defects due to higher migration barriers. EELS and DBS-PALS measurements confirm bubble densities of 63–96 He/nm³ and the presence of sub-nanometer open volumes. Compared to monolithic samples, the Zr/Nb multilayers exhibit ∼50% lower irradiation-induced hardening and reduced He retention (11% vs. 17.5% in single-crystal Nb and 16% in polycrystalline Zr). These findings highlight the role of interfaces in driving asymmetric radiation damage and demonstrate the effectiveness of BCC Nb layers in mitigating defect growth. Overall, Zr/Nb multilayers are established as a superior alternative to conventional single- and polycrystalline materials for extreme irradiation environments.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"301 ","pages":"Article 121579"},"PeriodicalIF":9.3,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145127854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unique properties of the electronic structure of alluaudite sodium iron sulfate cathode material and the impact on its electrochemical performance","authors":"J. Molenda ,&nbsp;J. Tobola ,&nbsp;A. Milewska ,&nbsp;A. Budziak ,&nbsp;W. Zając ,&nbsp;M. Wolczko ,&nbsp;K. Dziedzic-Kocurek ,&nbsp;M. Nowak ,&nbsp;K. Kałahurska ,&nbsp;N. Imam ,&nbsp;K. Henkel ,&nbsp;J.I. Flege ,&nbsp;E. Zschech","doi":"10.1016/j.actamat.2025.121582","DOIUrl":"10.1016/j.actamat.2025.121582","url":null,"abstract":"<div><div>This work presents the study of the electronic structure of alluaudite-type Na_2.5Fe_1.75(SO₄)₃ and its impact on electrochemical performance as a cathode material for sodium-ion batteries (SIBs). Density functional theory calculations using the KKR-CPA method (Korringa–Kohn–Rostoker combined with the coherent potential approximation) revealed the diverse electrochemical activity of sodium ions occupying different sites within the alluaudite framework. Notably, an unprecedented contribution of sodium atoms to the overall electronic density of states near the Fermi level (dominated by Fe-d and O-p states) was observed – a feature not detected in layered transition metal oxide cathodes.</div><div>A high-purity Na_2.5Fe_1.75(SO₄)₃ cathode material was synthesized via an optimized solid-state route. Using a multi-technique approach – including X-ray diffraction, scanning electron microscopy, Mössbauer spectroscopy, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and Raman spectroscopy – the evolution of the electronic structure and electrochemical behavior during sodium (de)intercalation was comprehensively characterized, providing deep insights into the sodium storage mechanism. <em>Operando</em> and in situ X-ray diffraction further tracked structural changes during cycling, showing that the material undergoes a reversible amorphization at deep sodium extraction.</div><div>Electrochemical tests demonstrated stable cycling with minimal capacity fade (only 2.5 % after 300 cycles at C/2), highlighting the high structural integrity and promise of this optimized cathode material.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"301 ","pages":"Article 121582"},"PeriodicalIF":9.3,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145183322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Local structure and lithium transport in Zr- and Hf-Doped LiTa2PO8 ceramics","authors":"P. Ren ,&nbsp;W. Ślubowska–Walkusz ,&nbsp;K. Pachulska ,&nbsp;C. Jastrzębski ,&nbsp;A.T. Krawczyńska ,&nbsp;I. Sobrados ,&nbsp;V. Diez–Gómez ,&nbsp;J. Sanz ,&nbsp;Y. Yue ,&nbsp;I. Abrahams ,&nbsp;K. Kwatek","doi":"10.1016/j.actamat.2025.121578","DOIUrl":"10.1016/j.actamat.2025.121578","url":null,"abstract":"<div><div>Among the various ceramic oxide-based Li-ion conductors, LiTa₂PO₈ has emerged as a promising candidate for application as an electrolyte in solid state lithium batteries. Here, the effects on local structure of substitution at the Ta site in the systems Li₁₊<em>_x</em>Ta₁₋<em>_x</em>M<em>_x</em>PO₈ (<em>M</em> = Hf or Zr) are investigated using a combination of neutron total scattering, ⁶Li and ³¹P solid state NMR and Raman spectroscopies, supported by microstructural and electrical measurements. In both the Hf and Zr substituted systems a limited solid solution up to <em>x</em> = 0.05 is observed. Structural analysis of the <em>x</em> = 0.05 compositions reveals Li-ions to be distributed over four 5-coordinate sites, which link to form chain-like diffusion channels in the 〈001〉 direction. Reverse Monte Carlo analysis of total neutron scattering data shows subtle differences in the Li-ion distribution in the two systems with the Hf substituted system exhibiting a more 2-dimensional character. Despite these structural differences the conductivity and activation energies of the two systems are very similar with room temperature values around 0.9 × 10⁻³ S cm⁻¹ and 1.6 × 10⁻³ S cm⁻¹ for the total and bulk conductivities, respectively, which are particularly high for oxide-based systems. There is some evidence of Li-ion clustering in the two systems which may suggest cooperative motion of Li-ions in the conduction process.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"301 ","pages":"Article 121578"},"PeriodicalIF":9.3,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}