Acta Materialia最新文献_第9页

Size-dependent stress response of nanoscale B2 intermetallic precipitates revealed by in-situ high-energy X-ray diffraction

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2025-03-28 DOI: 10.1016/j.actamat.2025.120967

Javad Mola , Steffen Scherbring , Ulrich Lienert , Alireza Zargaran , Horst Biermann , Puspendu Sahu

In-situ high-energy X-ray diffraction experiments under uniaxial loading revealed the stress distribution among austenite, ferrite, and nanoscale B2-(Ni,Fe)Al intermetallic precipitates embedded in the ferrite phase of an Al-added lightweight steel. Stress analysis based on the lattice strains induced by uniaxial tensile loading, while assuming a uniaxial stress state within the grains and neglecting residual stresses, indicated earlier yielding of austenite and the development of higher stresses in ferrite. Remarkably, at an applied true stress of nearly 1.0 GPa, stresses up to about 5.8 GPa were determined within the B2 precipitates. The stress level within the B2 precipitates, which exhibited a bimodal size distribution, was strongly size-dependent, with the finer population experiencing higher stresses. Due to the low Schmid factor for

{h k l} 〈 100 〉

slip as the preferred slip system in B2, plastic deformation of B2 in this hard orientation was enabled by

〈 111 〉

slip, aided by the penetration of

\frac{1}{2} 〈 111 〉

dislocations gliding on

{110}

planes in the cube-on-cube-related ferrite. The high stresses in B2 upon loading along the

〈 100 〉

direction raised the stress level in the surrounding ferrite, which is a likely cause of

{100}

cleavage in embrittled body-centered cubic steels. This study enhances our understanding of the micromechanical behavior of precipitation-strengthened alloys and elucidates how matrix-precipitate interactions influence macroscopic mechanical properties.

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引用次数: 0

Unexpected cellular growth of nanoporous gold during dealloying: Indication of vacancy injection?

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2025-03-27 DOI: 10.1016/j.actamat.2025.120959

Sheng-Nan Yang , Hui Xie , Fan Liu , Hai-Jun Jin

Dealloying can lead to stress corrosion cracking in engineering alloys or produce nanoporous materials for various functional applications. The role of bulk diffusion in dealloying has been debated since the 1960s when Pickering and Wagner proposed a vacancy-mediated lattice diffusion mechanism to explain the dealloying process. However, this mechanism was proven invalid because lattice diffusion is too slow to account for the rapid dealloying process at room temperature. Instead, it is now widely accepted that dealloying is dominated by the interfacial dissolution of more-reactive components, not necessarily involving lattice diffusion in the bulk. In this study, we report that the dealloying of Cu(Au) alloys at low potentials is incomplete, leaving some un-etched thin walls within the matrix of nanoporous gold. This results from the cellular growth of the nanoporous gold phase during dealloying, with cell walls composed of the precursor alloy phase slightly enriched with Au. This behavior is analogous to the cellular growth of solid phase during directional alloy solidification, suggesting that lattice diffusion may have occurred in the solid ahead of the dealloying front. Vacancy injection may lead to Au enrichment due to the inverse Kirkendall effect, enhancing the critical dealloying potential of the precursor ahead of the dealloying front, and triggering the unstable growth of the nanoporous gold phase. Although direct evidence is still lacking, our finding suggests that vacancy injection is involved in dealloying, which may have important implications on the design of corrosion-resistant alloys or novel nanoporous materials.

{"title":"Unexpected cellular growth of nanoporous gold during dealloying: Indication of vacancy injection?","authors":"Sheng-Nan Yang , Hui Xie , Fan Liu , Hai-Jun Jin","doi":"10.1016/j.actamat.2025.120959","DOIUrl":"10.1016/j.actamat.2025.120959","url":null,"abstract":"<div><div>Dealloying can lead to stress corrosion cracking in engineering alloys or produce nanoporous materials for various functional applications. The role of bulk diffusion in dealloying has been debated since the 1960s when Pickering and Wagner proposed a vacancy-mediated lattice diffusion mechanism to explain the dealloying process. However, this mechanism was proven invalid because lattice diffusion is too slow to account for the rapid dealloying process at room temperature. Instead, it is now widely accepted that dealloying is dominated by the interfacial dissolution of more-reactive components, not necessarily involving lattice diffusion in the bulk. In this study, we report that the dealloying of Cu(Au) alloys at low potentials is incomplete, leaving some un-etched thin walls within the matrix of nanoporous gold. This results from the cellular growth of the nanoporous gold phase during dealloying, with cell walls composed of the precursor alloy phase slightly enriched with Au. This behavior is analogous to the cellular growth of solid phase during directional alloy solidification, suggesting that lattice diffusion may have occurred in the solid ahead of the dealloying front. Vacancy injection may lead to Au enrichment due to the inverse Kirkendall effect, enhancing the critical dealloying potential of the precursor ahead of the dealloying front, and triggering the unstable growth of the nanoporous gold phase. Although direct evidence is still lacking, our finding suggests that vacancy injection is involved in dealloying, which may have important implications on the design of corrosion-resistant alloys or novel nanoporous materials.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"290 ","pages":"Article 120959"},"PeriodicalIF":8.3,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143723407","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}

引用次数: 0

Structure, phase transitions and hard magnetic properties of ternary Fe1.93(P1-xSix) compounds with x ≤ 0.5

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2025-03-27 DOI: 10.1016/j.actamat.2025.120991

Z. Surilemu , L.L. Bao , H. Yibole , S. Erdmann , H.İ. Sözen , T. Klüner , F. Guillou

Fe₂(P,Si) ternary derivatives from the Fe₂P parent hexagonal compound have so far received less attention than their quaternary counterparts, such as the (Mn,Fe)₂(P,Si) giant magnetocaloric materials; Yet, Fe₂(P,Si) compounds present an intriguing phase diagram with the development of a body-centered orthorhombic (BCO) structure when Si substitutes P. Here, we revisit their crystal structure and magnetic properties with the objective of establishing the properties of orthorhombic Fe_1.93P_1-_xSi_x compounds. The BCO to Fe₂P-type transition observed in Si substituted samples is found to be of first-order type and associated with a significant latent heat, a large volume discontinuity and an electrical transport anomaly. Furthermore, the potential for inducing this transition through the application of external fields was investigated. It revealed that the relatively modest difference in magnetization between the hexagonal and BCO structures renders the transition more sensitive to physical pressure. The recent surge of interest in the application of Fe₂P-type materials as permanent magnets also prompted us to investigate their magneto-crystalline anisotropy. A uniaxial anisotropy is found even in the BCO phase, with a large anisotropy constant of approximately 0.86 MJm⁻³ at room temperature. In combination with Curie temperatures which are much higher than room temperature, this makes BCO compounds potential rare-earth free permanent magnets, as demonstrated by the observation of a finite coercivity in BCO Fe_1.93P_0.6Si_0.4 ball milled powders (H_C ≈ 1.5 kOe). This work reveals that the exploration of Fe₂P materials for permanent magnet applications should not be limited to the hexagonal structure.

{"title":"Structure, phase transitions and hard magnetic properties of ternary Fe1.93(P1-xSix) compounds with x ≤ 0.5","authors":"Z. Surilemu , L.L. Bao , H. Yibole , S. Erdmann , H.İ. Sözen , T. Klüner , F. Guillou","doi":"10.1016/j.actamat.2025.120991","DOIUrl":"10.1016/j.actamat.2025.120991","url":null,"abstract":"<div><div>Fe<sub>2</sub>(P,Si) ternary derivatives from the Fe<sub>2</sub>P parent hexagonal compound have so far received less attention than their quaternary counterparts, such as the (Mn,Fe)<sub>2</sub>(P,Si) giant magnetocaloric materials; Yet, Fe<sub>2</sub>(P,Si) compounds present an intriguing phase diagram with the development of a body-centered orthorhombic (BCO) structure when Si substitutes P. Here, we revisit their crystal structure and magnetic properties with the objective of establishing the properties of orthorhombic Fe<sub>1.93</sub>P<sub>1-</sub><em><sub>x</sub></em>Si<em><sub>x</sub></em> compounds. The BCO to Fe<sub>2</sub>P-type transition observed in Si substituted samples is found to be of first-order type and associated with a significant latent heat, a large volume discontinuity and an electrical transport anomaly. Furthermore, the potential for inducing this transition through the application of external fields was investigated. It revealed that the relatively modest difference in magnetization between the hexagonal and BCO structures renders the transition more sensitive to physical pressure. The recent surge of interest in the application of Fe<sub>2</sub>P-type materials as permanent magnets also prompted us to investigate their magneto-crystalline anisotropy. A uniaxial anisotropy is found even in the BCO phase, with a large anisotropy constant of approximately 0.86 MJm<sup>−3</sup> at room temperature. In combination with Curie temperatures which are much higher than room temperature, this makes BCO compounds potential rare-earth free permanent magnets, as demonstrated by the observation of a finite coercivity in BCO Fe<sub>1.93</sub>P<sub>0.6</sub>Si<sub>0.4</sub> ball milled powders (<em>H</em><sub>C</sub> ≈ 1.5 kOe). This work reveals that the exploration of Fe<sub>2</sub>P materials for permanent magnet applications should not be limited to the hexagonal structure.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"291 ","pages":"Article 120991"},"PeriodicalIF":8.3,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143723411","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}

引用次数: 0

Amorphous/nanocrystalline composite structure strategy for MoAlB: Achieving rapid formation and gradual growth of α-Al2O3 scale at 1200 °C

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2025-03-26 DOI: 10.1016/j.actamat.2025.120986

Yagang Zhang, Guojun Zhang, Zhangwen Xie, Tao Wang, Caixia Wang, Quan Zhao, Boyan Wang

MoAlB, with a blend of metallic and ceramic attributes, receives special attention for high-temperature protective applications. Nevertheless, the formation of volatile oxides resulting from Al depletion accelerates the degradation of MoAlB. In this study, we adopted a configurational design strategy specifically targeting the in-situ precipitation of MoAlB nanocrystals within amorphous composites to achieve an amorphous/nanocrystalline composite structure of MoAlB (ACCS-MoAlB), for enhancing its oxidation resistance and elucidating the atomic-level oxidation mechanism of MoAlB. The obtained ACCS-MoAlB sample exhibited remarkable resistance to oxidation in ambient air at 1200 °C. This is because the rapid formation of a protective α-Al₂O₃ scale generated by the synergistic interaction between metastable amorphous composites (resistant to oxygen permeation) and MoAlB nanocrystals (exhibiting selective oxidation behavior), as well as the slow growth characteristics of the scale due to the nucleation and growth of both these structural units exposed to thermal conditions during the oxidation process. Among them, the selective oxidation behavior of MoAlB was observed as a result of vacancy-mediated preferential outward migration of Al along the [100] direction. Furthermore, the good adhesion between the oxide scale and the Al-depleted MoAlB matrix was found to originate from the dislocation-free coherent epitaxial growth of α-Al₂O₃.

混合了金属和陶瓷特性的 MoAlB 在高温保护应用中受到特别关注。然而，铝耗尽后形成的挥发性氧化物会加速 MoAlB 的降解。在本研究中，我们采用了一种构型设计策略，专门针对非晶复合材料中 MoAlB 纳米晶体的原位沉淀，以实现 MoAlB 的非晶/纳米晶复合结构（ACCS-MoAlB），从而增强其抗氧化性并阐明 MoAlB 的原子级氧化机制。所获得的 ACCS-MoAlB 样品在 1200 °C 的环境空气中表现出显著的抗氧化性。这是因为在氧化过程中，非晶态复合材料（抗氧渗透）和 MoAlB 纳米晶体（表现出选择性氧化行为）之间的协同作用迅速形成了保护性的 α-Al2O3 鳞片，同时由于这两种结构单元在热条件下成核和生长，鳞片具有缓慢生长的特点。其中，MoAlB 的选择性氧化行为是空位介导的 Al 沿 [100] 方向优先外移的结果。此外，还发现氧化鳞片与贫铝 MoAlB 基体之间的良好粘附性源于 αAl2O3 的无位错相干外延生长。

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引用次数: 0

Enhanced thermoelectric performance in pristine AgSbTe2 compound via rational design of Ag2Te formation

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2025-03-25 DOI: 10.1016/j.actamat.2025.120985

Zeqing Hu , Minhui Yuan , Wenjie Li , Sining Wang , Jingfeng Li , Jiahao Jiang , Jing Shuai , Yanglong Hou

AgSbTe₂ has garnered considerable attention in the thermoelectric community due to its excellent thermoelectric properties in the medium to low-temperature region. However, its electrical transport performance is significantly affected due to both the Ag₂Te secondary phase and intrinsic defects. Here, a two-step prepared strategy is employed to promote synergistic optimization between the concentration of Ag vacancies and the mass percentages of Ag₂Te nanoprecipitate, resulting in a significant improvement in carrier mobility from ∼192.89 to ∼375.71 cm² V⁻¹ s⁻¹ at 300 K. Additionally, the nanoprecipitates and dislocation introduced through the rational design of Ag₂Te formation leads to a remarkable reduction in thermal conductivity. A maximum figure of merit of ∼1.18 at 548 K and an average figure of merit of ∼0.94 at 300–633 K were obtained for QA-AgSbTe₂ (quenching temperature (Q) = 773 K, Annealing time (A) = 24 h), surpassing those of pristine AgSbTe₂ compound with pervasive Ag₂Te. This work reveals that the carrier and phonon transport performance of AgSbTe₂ can be effectively decoupled by the optimization of Ag vacancy concentration and introduction of dislocation via adjusting mass percentages of Ag₂Te nanoprecipitate.

AgSbTe2 由于在中低温区域具有出色的热电性能，在热电界引起了广泛关注。然而，由于 Ag2Te 的次生相和内在缺陷，其电传输性能受到很大影响。本文采用了两步制备策略，促进了 Ag 空位浓度与 Ag2Te 纳米沉淀质量百分比之间的协同优化，从而显著提高了载流子在 300 K 时的迁移率，从 192.89 升至 375.71 cm2 V-1 s-1。QA-AgSbTe2 （淬火温度 (Q) = 773 K，退火时间 (A) = 24 h）在 548 K 时的最大优越性为 ∼1.18，在 300-633 K 时的平均优越性为 ∼0.94，超过了含有大量 Ag2Te 的原始 AgSbTe2 化合物。这项工作揭示了通过调整 Ag2Te 纳米沉淀物的质量百分比来优化 Ag 空位浓度和引入位错，可以有效地解耦 AgSbTe2 的载流子和声子传输性能。

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引用次数: 0

A layer model for the kinetics of segregation in planar defects in multi-component materials 多组分材料平面缺陷偏析动力学层模型

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2025-03-25 DOI: 10.1016/j.actamat.2025.120948

Dongsheng Wen , Victoria Tucker , Michael S. Titus

Suzuki segregation and local phase transformations are widely observed across materials with extended planar defects, offering opportunities to design novel high-temperature and functional materials enabled by the nanoscale two-dimensional defects. However, the kinetics of the segregation process are not well understood despite intensive efforts have been made to investigate the segregation profiles at equilibrium and non-equilibrium conditions. In this work, a new model is proposed to study the temperature- and time-dependent segregation process to facilitate the research of this phenomenon. The model is established from the segregation energy landscape across the planar defects and the interlayer diffusion process. The model is applied to the Co-Ni binary alloys, Co-based superalloys, and Ni-based superalloys to understand the characteristics of segregation at equilibrium, the timescale required to reach equilibrium, and the influence of solute–solute interactions in the process. The kinetic model can be implemented with the thermodynamic models of segregation energy, which is demonstrated for a Ni-Co-Cr system. Based on the findings, a time–temperature–segregation diagram is proposed to determine the heat treatment parameters or thermal exposure profiles to achieve Suzuki segregation and local phase transformation for material design.

在具有扩展平面缺陷的材料中广泛观察到铃木偏析和局部相变，这为利用纳米级二维缺陷设计新型高温功能材料提供了机会。然而，尽管人们对平衡和非平衡条件下的偏析剖面进行了深入研究，但对偏析过程的动力学仍不甚了解。本研究提出了一个研究随温度和时间变化的偏析过程的新模型，以促进对这一现象的研究。该模型是根据跨平面缺陷的偏析能谱和层间扩散过程建立的。该模型适用于 Co-Ni 二元合金、Co 基超耐热合金和 Ni 基超耐热合金，以了解平衡时的偏析特征、达到平衡所需的时间尺度以及过程中溶质-溶质相互作用的影响。动力学模型可与偏析能热力学模型结合使用，这一点已在镍-钴-铬体系中得到证实。根据研究结果，提出了时间-温度-偏析图，以确定热处理参数或热暴露曲线，从而实现材料设计中的铃木偏析和局部相变。

{"title":"A layer model for the kinetics of segregation in planar defects in multi-component materials","authors":"Dongsheng Wen , Victoria Tucker , Michael S. Titus","doi":"10.1016/j.actamat.2025.120948","DOIUrl":"10.1016/j.actamat.2025.120948","url":null,"abstract":"<div><div>Suzuki segregation and local phase transformations are widely observed across materials with extended planar defects, offering opportunities to design novel high-temperature and functional materials enabled by the nanoscale two-dimensional defects. However, the kinetics of the segregation process are not well understood despite intensive efforts have been made to investigate the segregation profiles at equilibrium and non-equilibrium conditions. In this work, a new model is proposed to study the temperature- and time-dependent segregation process to facilitate the research of this phenomenon. The model is established from the segregation energy landscape across the planar defects and the interlayer diffusion process. The model is applied to the Co-Ni binary alloys, Co-based superalloys, and Ni-based superalloys to understand the characteristics of segregation at equilibrium, the timescale required to reach equilibrium, and the influence of solute–solute interactions in the process. The kinetic model can be implemented with the thermodynamic models of segregation energy, which is demonstrated for a Ni-Co-Cr system. Based on the findings, a time–temperature–segregation diagram is proposed to determine the heat treatment parameters or thermal exposure profiles to achieve Suzuki segregation and local phase transformation for material design.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"290 ","pages":"Article 120948"},"PeriodicalIF":8.3,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143703375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Generative 3D reconstruction of Ti-6Al-4V basketweave microstructures by optimization of differentiable microstructural descriptors 通过优化可变微观结构描述符生成 Ti-6Al-4V 篮织微观结构的三维重建

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2025-03-25 DOI: 10.1016/j.actamat.2025.120947

Vincent Blümer , Ali Reza Safi , Celal Soyarslan , Benjamin Klusemann , Ton van den Boogaard

We present a methodology for the generative reconstruction of 3D microstructures from 2D cross-sectional electron backscatter diffraction micrographs. The method is applied to Ti-6Al-4V processed by laser powder bed fusion, where a high amount of basketweave morphology is observed, which arises from the solid-state

β \to α

-transition upon cooling. Prior-

β

-grain reconstruction is performed and the out-of-plane orientation of the observed grains is obtained leveraging Burgers orientation relationship. Microstructural descriptors related to convolutional neural networks are extracted from the 2D micrographs, and used for cross-section-based optimization of pixel values in a 3D volume. In order to reconstruct crystallographic orientations, the orientation distribution of the basketweave microstructure is reduced to a discrete set of characteristic orientations, which are sequentially reconstructed as separate components. Our reconstructions capture the characteristic lath morphology that is typically observed in powder bed fusion-processed Ti-6Al-4V and perform well in comparisons of chord length, as well as grain size, aspect ratio, and axis orientation distributions.

{"title":"Generative 3D reconstruction of Ti-6Al-4V basketweave microstructures by optimization of differentiable microstructural descriptors","authors":"Vincent Blümer , Ali Reza Safi , Celal Soyarslan , Benjamin Klusemann , Ton van den Boogaard","doi":"10.1016/j.actamat.2025.120947","DOIUrl":"10.1016/j.actamat.2025.120947","url":null,"abstract":"<div><div>We present a methodology for the generative reconstruction of 3D microstructures from 2D cross-sectional electron backscatter diffraction micrographs. The method is applied to Ti-6Al-4V processed by laser powder bed fusion, where a high amount of basketweave morphology is observed, which arises from the solid-state <span><math><mrow><mi>β</mi><mo>→</mo><mi>α</mi></mrow></math></span>-transition upon cooling. Prior-<span><math><mi>β</mi></math></span>-grain reconstruction is performed and the out-of-plane orientation of the observed grains is obtained leveraging Burgers orientation relationship. Microstructural descriptors related to convolutional neural networks are extracted from the 2D micrographs, and used for cross-section-based optimization of pixel values in a 3D volume. In order to reconstruct crystallographic orientations, the orientation distribution of the basketweave microstructure is reduced to a discrete set of characteristic orientations, which are sequentially reconstructed as separate components. Our reconstructions capture the characteristic lath morphology that is typically observed in powder bed fusion-processed Ti-6Al-4V and perform well in comparisons of chord length, as well as grain size, aspect ratio, and axis orientation distributions.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"291 ","pages":"Article 120947"},"PeriodicalIF":8.3,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143695261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multi-Functional Mo-Ion interlayer engineering facilitates high performance aqueous zinc-ion batteries

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2025-03-24 DOI: 10.1016/j.actamat.2025.120960

Zihan Wang , Heshun Geng , Pengcheng Song , Peng Cui , Fang Hu , Junhua You , Kai Zhu

The widespread application of vanadium oxide cathodes in aqueous zinc-ion batteries (AZIBs) remains constrained by three fundamental limitations: structural dissolution in electrolyte media, inadequate electronic conductivity, and sluggish Zn²⁺ diffusion kinetics. To concurrently overcome these challenges, we engineered Mo-intercalated V₃O₇ cathodes (denoted as Mo_0.06V₃O₇) through strategic interlayer modification. This multifunctional design achieves: enhanced structural integrity through interlayer stabilization, improved charge transfer capability, and optimized Zn²⁺ transport pathways with reduced diffusion energy barriers. The optimized cathode delivers a specific capacity of 460 mAh g⁻¹ at 0.2 A g⁻¹ and demonstrates exceptional cyclability with 91.8 % capacity retention after 20,000 cycles at 10 A g⁻¹. Notably, temperature-dependent testing confirms stable operation across -20 to 40 °C, addressing a critical limitation in practical deployment scenarios. Density functional theory (DFT) calculations reveal three synergistic mechanisms: Mo intercalation strengthens V-O bonding (3.1 double bond energy increase), simultaneously modulating charge redistribution during Zn²⁺ insertion and effectively reducing electrostatic interactions between zinc ions and host framework (2.5 double diffusion barrier decrease). This interlayer engineering strategy establishes a materials design paradigm applicable to diverse vanadium oxide systems, potentially accelerating the development of high-performance AZIB for grid-scale energy storage applications.

{"title":"Multi-Functional Mo-Ion interlayer engineering facilitates high performance aqueous zinc-ion batteries","authors":"Zihan Wang , Heshun Geng , Pengcheng Song , Peng Cui , Fang Hu , Junhua You , Kai Zhu","doi":"10.1016/j.actamat.2025.120960","DOIUrl":"10.1016/j.actamat.2025.120960","url":null,"abstract":"<div><div>The widespread application of vanadium oxide cathodes in aqueous zinc-ion batteries (AZIBs) remains constrained by three fundamental limitations: structural dissolution in electrolyte media, inadequate electronic conductivity, and sluggish Zn²⁺ diffusion kinetics. To concurrently overcome these challenges, we engineered Mo-intercalated V<sub>3</sub>O<sub>7</sub> cathodes (denoted as Mo<sub>0.06</sub>V<sub>3</sub>O<sub>7</sub>) through strategic interlayer modification. This multifunctional design achieves: enhanced structural integrity through interlayer stabilization, improved charge transfer capability, and optimized Zn²⁺ transport pathways with reduced diffusion energy barriers. The optimized cathode delivers a specific capacity of 460 mAh <em>g</em><sup>−</sup>¹ at 0.2 A <em>g</em><sup>−</sup>¹ and demonstrates exceptional cyclability with 91.8 % capacity retention after 20,000 cycles at 10 A <em>g</em><sup>−</sup>¹. Notably, temperature-dependent testing confirms stable operation across -20 to 40 °C, addressing a critical limitation in practical deployment scenarios. Density functional theory (DFT) calculations reveal three synergistic mechanisms: Mo intercalation strengthens V-O bonding (3.1 double bond energy increase), simultaneously modulating charge redistribution during Zn²⁺ insertion and effectively reducing electrostatic interactions between zinc ions and host framework (2.5 double diffusion barrier decrease). This interlayer engineering strategy establishes a materials design paradigm applicable to diverse vanadium oxide systems, potentially accelerating the development of high-performance AZIB for grid-scale energy storage applications.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"290 ","pages":"Article 120960"},"PeriodicalIF":8.3,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143695294","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}

引用次数: 0

New noncollinear antiferromagnet Mn3Al for antiferromagnetic spintronics

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2025-03-24 DOI: 10.1016/j.actamat.2025.120939

Bing Lv , Mingsu Si , Long Cheng , Zhongjie Yan , Xiaolin Li , Cunxu Gao

Hexagonal noncollinear antiferromagnets, such as Mn₃Sn, Mn₃Ge, and Mn₃Ga, have garnered significant attention in recent years due to their potential for supplying large anisotropic anomalous and spin Hall conductance. In particular, noncollinear antiferromagnetic tunnel junctions have been fabricated, demonstrating their applications in antiferromagnetic spintronics in future. However, hexagonal Mn₃Al, a noncollinear antiferromagnet that has non-heavy metal elements, has never been reported. In this study, we not only predict the noncollinear antiferromagnet Mn₃Al through first-principles calculations and experimentally confirm the existence of hexagonal Mn₃Al, but also predict the existence of large anomalous Hall conductance for Mn₃Al. Our calculations reveal that Mn₃Al can be utilized in antiferromagnetic tunnel junctions and possesses anisotropic anomalous Hall conductance. Our calculations show a large

σ_{z x}

= 1398

{(Ω⋅cm)}^{- 1}

above the Fermi level, which is caused by the Weyl points in momentum space for Mn₃Al.

σ_{z x}

could be raised from 99.7

{(Ω⋅cm)}^{- 1}

for Mn₃Al to 412

{(Ω⋅cm)}^{- 1}

for Mn₃Al_0.5Si_0.5 at Fermi level by substituting the Al atoms with Si atoms. More Si content further raises the value of

σ_{z x}

to a maximum 952

{(Ω⋅cm)}^{- 1}

for Mn₃Al_0.35Si_0.65 within the rigid band approximation. Furthermore, the films grown on Si(111) substrates suggest compatibility with semiconductor devices, thus broadening the applications of Mn₃Al and expanding the family of noncollinear antiferromagnets.

{"title":"New noncollinear antiferromagnet Mn3Al for antiferromagnetic spintronics","authors":"Bing Lv , Mingsu Si , Long Cheng , Zhongjie Yan , Xiaolin Li , Cunxu Gao","doi":"10.1016/j.actamat.2025.120939","DOIUrl":"10.1016/j.actamat.2025.120939","url":null,"abstract":"<div><div>Hexagonal noncollinear antiferromagnets, such as Mn<sub>3</sub>Sn, Mn<sub>3</sub>Ge, and Mn<sub>3</sub>Ga, have garnered significant attention in recent years due to their potential for supplying large anisotropic anomalous and spin Hall conductance. In particular, noncollinear antiferromagnetic tunnel junctions have been fabricated, demonstrating their applications in antiferromagnetic spintronics in future. However, hexagonal Mn<sub>3</sub>Al, a noncollinear antiferromagnet that has non-heavy metal elements, has never been reported. In this study, we not only predict the noncollinear antiferromagnet Mn<sub>3</sub>Al through first-principles calculations and experimentally confirm the existence of hexagonal Mn<sub>3</sub>Al, but also predict the existence of large anomalous Hall conductance for Mn<sub>3</sub>Al. Our calculations reveal that Mn<sub>3</sub>Al can be utilized in antiferromagnetic tunnel junctions and possesses anisotropic anomalous Hall conductance. Our calculations show a large <span><math><msub><mrow><mi>σ</mi></mrow><mrow><mi>z</mi><mi>x</mi></mrow></msub></math></span> = 1398 <span><math><msup><mrow><mi>(Ω⋅cm)</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> above the Fermi level, which is caused by the Weyl points in momentum space for Mn<sub>3</sub>Al. <span><math><msub><mrow><mi>σ</mi></mrow><mrow><mi>z</mi><mi>x</mi></mrow></msub></math></span> could be raised from 99.7 <span><math><msup><mrow><mi>(Ω⋅cm)</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> for Mn<sub>3</sub>Al to 412 <span><math><msup><mrow><mi>(Ω⋅cm)</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> for Mn<sub>3</sub>Al<sub>0.5</sub>Si<sub>0.5</sub> at Fermi level by substituting the Al atoms with Si atoms. More Si content further raises the value of <span><math><msub><mrow><mi>σ</mi></mrow><mrow><mi>z</mi><mi>x</mi></mrow></msub></math></span> to a maximum 952 <span><math><msup><mrow><mi>(Ω⋅cm)</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> for Mn<sub>3</sub>Al<sub>0.35</sub>Si<sub>0.65</sub> within the rigid band approximation. Furthermore, the films grown on Si(111) substrates suggest compatibility with semiconductor devices, thus broadening the applications of Mn<sub>3</sub>Al and expanding the family of noncollinear antiferromagnets.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"290 ","pages":"Article 120939"},"PeriodicalIF":8.3,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143678021","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}

引用次数: 0

Ultra-flexible organic-inorganic hybrid Bi2Te3 thin films for thermoelectric generators

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2025-03-24 DOI: 10.1016/j.actamat.2025.120971

Dong Yang , Ning Chen , Mohammad Nisar , Zilong Zhang , Fu Li , Mazhar Hussain Danish , Hongli Ma , Guangxing Liang , Xianghua Zhang , Yue-Xing Chen , Zhuang-Hao Zheng

Achieving high thermoelectric (TE) performance and flexibility is essential for wearable electronics. Here, an organic-inorganic hybrid strategy incorporating methylammonium lead iodide (MAPbI₃) into Bi₂Te₃ thin films enhances both TE and mechanical properties. Pb/I incorporate into Bi₂Te₃ lattice, improving electrical conductivity via enhanced carrier transport and moderate doping effects. Meanwhile, amorphous phases derived from MA-related species strengthen phonon scattering, reducing κ_l+κ_bi from 1.1 Wm^-1K^-1 to 0.1 Wm^-1K^-1. As a result, the zT value improves from 0.08 to 0.94 at 250 °C. Moreover, the amorphization effect induced by the amorphous inclusions enhances flexibility by reducing the Young's modulus, yielding a resistance change of <7 % (ΔR/R₀) after bending. Specifically, the 0.6 wt. % sample exhibits only a 2.5 % resistance change after 5000 bending cycles. Finally, a flexible TE generator fabricated with hybrid films and Ag electrodes delivers a high output power of 35.3 nW under a 20 °C temperature gradient, highlighting the potential of this hybrid approach for wearable electronics.

{"title":"Ultra-flexible organic-inorganic hybrid Bi2Te3 thin films for thermoelectric generators","authors":"Dong Yang , Ning Chen , Mohammad Nisar , Zilong Zhang , Fu Li , Mazhar Hussain Danish , Hongli Ma , Guangxing Liang , Xianghua Zhang , Yue-Xing Chen , Zhuang-Hao Zheng","doi":"10.1016/j.actamat.2025.120971","DOIUrl":"10.1016/j.actamat.2025.120971","url":null,"abstract":"<div><div>Achieving high thermoelectric (TE) performance and flexibility is essential for wearable electronics. Here, an organic-inorganic hybrid strategy incorporating methylammonium lead iodide (MAPbI<sub>3</sub>) into Bi<sub>2</sub>Te<sub>3</sub> thin films enhances both TE and mechanical properties. Pb/I incorporate into Bi<sub>2</sub>Te<sub>3</sub> lattice, improving electrical conductivity via enhanced carrier transport and moderate doping effects. Meanwhile, amorphous phases derived from MA-related species strengthen phonon scattering, reducing κ<sub>l</sub>+κ<sub>bi</sub> from 1.1 Wm<sup>-1</sup>K<sup>-1</sup> to 0.1 Wm<sup>-1</sup>K<sup>-1</sup>. As a result, the <em>zT</em> value improves from 0.08 to 0.94 at 250 °C. Moreover, the amorphization effect induced by the amorphous inclusions enhances flexibility by reducing the Young's modulus, yielding a resistance change of <7 % (<em>ΔR</em>/<em>R<sub>0</sub></em>) after bending. Specifically, the 0.6 wt. % sample exhibits only a 2.5 % resistance change after 5000 bending cycles. Finally, a flexible TE generator fabricated with hybrid films and Ag electrodes delivers a high output power of 35.3 nW under a 20 °C temperature gradient, highlighting the potential of this hybrid approach for wearable electronics.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"290 ","pages":"Article 120971"},"PeriodicalIF":8.3,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143695291","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}

引用次数: 0