COMPOSITES PART B-ENGINEERING
·
2022
·
IF 11.322
Fucheng Wang,Jinfeng Zhang,Kaixin Sun,Liwei Quan,Jing Wang,Naiqin Zhao,Chunsheng Shi,Shijian Zheng
Interfacial bonding is an important factor affecting the mechanical properties of composites. The interface between the in-situ synthesized ceramic phase and the metal matrix is considered ideal, so little attention is paid to the interfacial modification. In this work, we found that interfacial segregation affects the growth of the MgAlB 4 whisker and the interface of reinforcement and matrix in the composites. Systematic experiments and theoretical calculations indicate Fe solute prefer to segregate at the MgAlB 4 - { 10 1 ‾ 0 } /Al interfaces in in-situ synthesized MgAlB 4 /Al composites, which is helpful to reduce system free energy. On the one hand, Fe segregation induces the whisker coarsening and the formation of planar defects with a sandwich structure formed by a layer of Fe atoms and two layers of Al atoms in coarse-whiskers, on the other hand, it improves the interfacial strength . Although extra Fe aggravates the whisker coarsening, the synergistic reinforcing effect of the whiskers and the extra Fe is greater than the sum of their individual reinforcing effects. This work demonstrates that interfacial segregation can be used to modulate the size of reinforcements and improve interfacial strength.
研究领域:
材料科学
·
力学
✓ 已验证
产品关联
DOI
高影响因子
COMPUTATIONAL MATERIALS SCIENCE
·
2025
·
IF 3.3
Yan Zhu,Jianke Tian,Yiwen Liu,Zhaocang Meng
Beryllium has been determined as one prospective neutron multiplier materials in nuclear fusion power plant. During the manufacturing of beryllium pebbles, impurities will be inevitably introduced into the beryllium matrix. However, the distribution of impurities in beryllium is lack of investigation. Consequently, in the present work, combined with experimental techniques and first-principles calculations, the solution and segregation behaviors of nonmetallic and metallic impurities in beryllium as well as the in-depth mechanism have been thoroughly investigated. The experimental observations have shown that the nonmetallic impurities of oxygen, carbon and silicon, the metallic impurities of iron, aluminium, magnesium, zinc, lead and copper could dissolve in bulk beryllium. The calculation results have shown that the solution energies of those impurity atoms is low except for that of lead. Furthermore, it has also been found experimentally that oxygen and iron could segregate at grain boundaries of beryllium. The segregation energy of oxygen and iron atoms at two grain boundaries of Σ 13 { 10 1 ̄ 1 } and Σ 11 { 10 1 ̄ 2 } are negative, which means that both oxygen and iron atoms have strong tendency to segregate at grain boundaries of beryllium. The results firmly demonstrate the observed phenomenon. The current work has contributed to a further understanding of the distribution of impurity atoms in beryllium, facilitating the manufacturing of beryllium pebbles.
研究领域:
材料科学
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核工程
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物理冶金学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Lifeng Jiang,Shuyue Tan,Rongchun Chen,Jingwei Xian,Hongrui Li,Donghu Zhou,Huijun Kang,Zongning Chen,Enyu Guo,Tongmin Wang
Grain boundary (GB) engineering includes grain size and GB segregation. Grain size has been proven to affect the electrical properties of Mg3(Sb, Bi)2 at low temperatures. However, the formation mechanism of GB segregation and what kind of GB segregation is beneficial to the performance are still unclear. Here, the Ga/Bi cosegregation at GBs and Mg segregation within grains optimize the transport of electrons and phonons simultaneously. Ga/Bi cosegregation promotes the formation of Janus-like structures due to the diverse ordering tendencies of liquid Mg3Sb2 and Mg3Bi2 and the absence of a solid solution of Ga/Bi. The Janus-like structure significantly reduces the room-temperature lattice thermal conductivity by introducing diverse microdefects. Meanwhile, a coherent interface between the nano Mg segregation region and the matrix is formed, which reduces the thermal conductivity without affecting the carrier transport. Furthermore, the band structure calculations show that Ga doping introduces the resonance level, increasing the Seebeck coefficient. Finally, the lattice thermal conductivity reaches ∼0.4 W m–1 K–1, and a high average ZT of 1.21 between 323 and ∼773 K is achieved for Mg3.2Y0.02Ga0.03Sb1.5Bi0.5. This work provides guidance for improving the thermoelectric performance via designing cosegregation.
研究领域:
材料科学
·
热电材料
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2022
·
IF 13.599
Yanwei Zhu,Jianqiao Shi,Yingying Li,Yuxuan Lu,Bo Zhou,Shuangyin Wang,Yuqin Zou
Surface segregation is ubiquitous in multi-component materials and is of great important for catalysis but little is known on the surface structure under graphene encapsulation. Here, we show that the graphene encapsulated CoCu performs well for the electrocatalytic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) with the onset potential before 1.23 V RHE and a nearly 100% selectivity of FDCA under 1.4 V RHE . From the experimental results, the unprecedented catalytic performance was attributed to local structural distortion and sub-nanometer lattice composition of the CoCu surface. We accurately show the dispersed Cu doped Co 3 O 4 nano-islands with a lot of edge sites on the bimetallic Co-Cu surface. While, the gradient components effectively facilitate the establishment of built-in electric field and accelerate the charge transfer. Theoretical and experimental results reveal that the surface Co and neighbouring Cu atoms in sub-nanometer lattice synergistically promote the catalysis of HMF. This work offers new insights into surface segregation in tuning the element spatial distribution for catalysis.
研究领域:
材料科学
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电化学
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催化反应
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2023
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IF 6.4
T. Zhang,H.W. Deng,Z.M. Xie,Y.W. Zhuang,S.Y. Peng,G. Hu,H. Lin
Improvement of the stability of nanocrystalline (NC) materials is always a challenge. In this paper, the high thermal stability is achieved in a representative NC W alloy by combining nano-segregation of Ti solute to W grain boundary (GBs), and in-situ formation of nano Ti–Zr–O particles, which provide both thermodynamic and kinetic stabilization effects through solute dragging and particle pinning. The recrystallization temperature of this bulk NC W alloy reaches up to 1600 °C, and these nanometric microstructures maintain stable under a long-time and high-temperature ordeal up to 1200 °C for 120 h. And its microhardness and micro-compressive yield strength are ∼17.0 and 5.14 GPa, respectively. In addition, this bulk NC W alloy has high irradiation stability due to the high densities of stabled GBs and phase boundaries. This work demonstrates the possibility of attaining high-stability bulk NC materials in terms of segregation of solutes at GBs and in-situ formation of ultrafine nanoparticles with a coherent interface with the W matrix.
研究领域:
材料科学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Cell Reports Physical Science
·
2023
·
IF 8.9
Zheng Hu,Hui Li,Wenbo Zhao,Wei Zhou,Shi Hu
Structural information in a disordered atomic system cannot be acquired from everyday X-ray diffractometers, so we have to resort to synchrotron resources. The pair distribution function from synchrotron X-ray and neutron scattering reflects the local bond information regardless of the crystallinity, but the limited access to these high-energy light resources prevents them from widespread use. Here, we develop a microstructure analysis framework to study immiscible binary alloys through the integration of local elemental segregation analysis, electron-based pair distribution function, the corresponding wavelet coherence spectrum, and ab initio level simulation. All the information can be obtained from an in-house transmission electron microscope equipped with an energy-dispersive spectroscope. A series of nanoparticles based on immiscible Pd-Ru alloys are chosen as model catalysts for the hydrogen evolution reaction, and the structure-performance relationship is established on the basis of the electrochemical tests and structural information from the analysis toolkit we developed.
研究领域:
材料科学
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催化化学
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电子显微学
✓ 已验证
DOI
高影响因子
Journal of Physics-Energy
·
2025
·Vol. 7
·期 2
·025002
·
IF 6.3
Jingwei Li,Zichao Wu,Yuxiang Shen,Yuefeng Song,Houfu Lv,Xiaomin Zhang,Guoxiong Wang
Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) is a conventional anode material for solid oxide electrolysis cells (SOECs) to catalyze oxygen evolution reactions (OERs). However, the inferior chemical stability of BSCF results in severe surface segregation and performance degradation under high temperatures. A critical challenge lies in alleviating surface segregation and preserving the high OER performance of BSCF anodes. Herein, lanthanides are introduced to substitute the Ba in BSCF, labeled as Ln0.5Sr0.5Co0.8Fe0.2O3−δ (LnSCF, Ln = La, Pr, Nd, Sm), to regulate its stability and performance. The introduction of La and Pr effectively enhances stability, suppresses surface segregation and maintains high OER activity. Continuous lattice oxygen loss and Co ion oxidation of LnSCF are demonstrated upon annealing in oxidizing atmosphere; thus, we propose that surface segregation is a self-regulation mechanism of perovskite lattice to tolerant oxidizing atmosphere. Perovskite oxides maintain structurally stable via decreasing A-site valence state and forming surface segregation. SOECs with La0.5Sr0.5Co0.8Fe0.2O3−δ anodes deliver an optimal current density of 1.69 A cm−2 at 1.6 V and stability for CO2 electrolysis at 800 °C, shedding light on designing advanced catalysts for high-temperature OER.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Xinyuan Zhou,Qiyan Sun,Xinlin Wang,Ruixue Zhang,Bin Li,Zexing Wu,Dehong Chen,Lei Wang,Guang-Rui Xu
Synthesis of cost-effective electrocatalysts for oxygen reduction reaction (ORR) has received wide attention due to their sluggish kinetics, which limits the development and application of fuel cell technique. In this work, we report a versatile synthetic approach to prepare a series of small-sized Ag@MNi (M = Pd, Pt, Rh, Ru) nanocrystals with core–shell structures by a simple solvothermal method. According to characterization analysis, surface segregation of Pd was proved in the outermost layer with the Pd-rich shell layer, which can regulate the adsorption energy of *OH. Electrochemical results show that the onset potential and half-wave potential of Ag@PdNi nanocrystals (Ag@PdNi NCs) are 1.005 and 0.913 V vs. RHE (reversible hydrogen electrode), respectively, with a Tafel slope of 55.31 mV dec -1 and strong ORR catalytic durability, which is similar to Ag@MNi (M = Pt, Rh, Ru) NCs and slightly higher than that of PdAg alloy nanoparticles (PdAg alloy NPs), PdNi alloy nanoparticles (PdNi alloy NPs), commercial Pd black and even commercial Pt/C, in alkaline medium. Density Functional (DFT) calculations show that the presence of Ag core effectively promotes the segregation of Pd atoms to the outer shell surface, where Ni provides better segregated substitution sites for Pd, which significantly improves the ORR activity and durability due to the electronic synergistic effect between Ag core nuclei and Pd shell can reduce the adsorption strength of OH ads .
研究领域:
材料科学
·
电化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Yinlin Chang,Tao Liu,Jingyuan Rao,Min Fu,Yijun Guo,Shuliang Zou,Dewen Tang,Zetian Tao
The safe immobilization of radiotoxic strontium (Sr) in high-level radioactive waste (HLW) remains a major challenge due to its tendency to segregate and leach under aqueous conditions. In this study, a surface vanadium (V) engineering strategy is proposed to enhance the chemical stability of Sr 2 Fe 1.5 Mo 0.5 O 6-δ (SFM) ceramics. V-doped samples (SFMV), synthesized via a sol-gel method with 0.05 mol V partially substituting Mo, show improved resistance to Sr migration. DFT calculations reveal that V modification increases the Sr migration barrier from 0.14 eV (in SFM) to 0.34 eV (in SFMV) and induces the formation of strong Fe-O-V, and Mo–O–V effectively suppressing Sr surface segregation. Additionally, the formation of SrMoO 4 phases may act as Sr sinks, further enhancing stability. Leaching tests show that the Sr release from SFMV drops from 7.43 × 10 −4 to 2.89 × 10 −6 g·cm −2 ·d −1 over 42 days, representing a 64 % reduction compared to pristine SFM. This work provides a promising strategy for designing durable ceramic hosts for Sr-containing HLW.
研究领域:
材料科学
·
核工程
·
环境化学
·
固态化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2025
·
IF 9.7
Yanling Zhou,Yang Gao,Guichan Chen,Mingyu Jiang,Dehong Huang,Zezhi Zeng,Yangjun Zhang,Dengjie Chen
Alkaline-earth segregation and low electronic conductivity restrict the practical applications of high-performance cathodes in solid oxide fuel cells (SOFCs) and protonic ceramic fuel cells (PCFCs). To address these issues, a unique electrode structure with a sintered active backbone coated with an in situ-formed porous net-like PrCoO 3 (PCO) layer is developed. The effectiveness of this strategy is demonstrated using Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3−δ (BSCF), known for unprecedented oxygen reduction activity but with a great tendency to cause segregation and low electrical conductivity. This design leverages the beneficial characteristics of BSCF and PCO: the BSCF backbone provides high oxygen reduction activity, while the porous net-like PCO layer generated in situ offers high electrical conductivity. More importantly, this approach has the ability to eliminate potential surface segregation and even utilize the segregation by element interdiffusion to form a coating layer with high oxygen reduction activity. Therefore, the PCO-coated BSCF cathode (BSCF–PCO) offers impressive cell performance with a low area-specific polarization resistance of 0.02 Ω cm 2 at 600 °C using a symmetric cell and a maximum power density of 1835 mW cm −2 at 600 °C using an anode-supported fuel cell, which are superior to the cells with the state-of-the-art BSCF (i.e., 0.04 Ω cm 2 and 987 mW cm −2 ). Furthermore, this strategy significantly boosts the activity of other cathode materials such as Ba 0.5 Sr 0.5 Fe 0.8 Zn 0.2 O 3−δ , a typical cathode for PCFCs. This study thus provides a facile, universal in situ strategy for constructing high-performance cathodes by removing and transforming surface segregation for SOFCs and PCFCs.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF RARE EARTHS
·
2024
·
IF 5.2
Zhe Wang,Mengke Yuan,Juntao Gao,Hongru Hao,Jingwei Li,Lingling Xu,Zhe Lv,Bo Wei
Cation segregation on cathode surfaces plays a key role in determining the activity and operational stability of solid oxide fuel cells (SOFCs). The double perovskite oxide PrBa 0.8 Ca 0.2 Co 2 O 5+ δ (PBCC) has been widely studied as an active cathode but still suffer from serious detrimental segregations. To enhance the cathode stability, a PBCC derived A-site medium-entropy Pr 0.6 La 0.1 Nd 0.1 Sm 0.1 Gd 0.1 Ba 0.8 Ca 0.2 Co 2 O 5+ δ (ME-PBCC) oxide was prepared and its segregation behaviors were investigated under different conditions. Compared with initial PBCC oxide, the segregations of BaO and Co 3 O 4 on the surface of ME-PBCC material are significantly suppressed, especially for Co 3 O 4 , which is attributed to its higher configuration entropy. Our results also confirm the improved electrochemical performance and structural stability of ME-PBCC material, enabling it as a promising cathode for SOFCs.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2019
·
IF 5.107
Yufeng Hao,Linjie Zhou,Yanlei Su,Zhongyi Jiang
Surface segregation method based on the collaborative self-assembly principle was proposed to construct anti-fouling membranes with fouling-resistant and fouling-release mechanisms (dual-defense mechanism). Graphene oxides (GO) functionalized with polyethyleneimine (PEI) and perfluorosulfonic acid (PFSA) were added simultaneously into the casting solution to prepare PVDF/PFSA/PEI-GO hybrid membranes through surface segregation along with phase inversion process. The PEI-GO of hydrophilicity and the PFSA of low surface energy were utilized as additives to incorporate dual-defense mechanism for anti-fouling membranes. Furthermore, the synergistic effect of PEI immobilized on GO and sulfonic acid groups on PFSA generated electrostatic interaction, improving the long-term stability of membranes in aqueous environment. In the oil/water separation performance experiments, PVDF/PFSA/PEI-GO-1% membranes exhibited the highest pure water permeability of 406.7 ± 15.6 L m −2 h −1 bar −1 , with flux decay rate ( DR t ) of 8.6%, and flux recovery rate ( FRR ) of 98.6%.
研究领域:
材料科学
·
膜技术
·
环境工程
·
高分子化学
·
界面科学
·
分离工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）