Magnetic metal has broad application prospects in the field of electromagnetic wave (EMW) absorption due to its excellent dielectric and magnetic properties. However, high density and poor chemical stability constrain their development potential. The combination of magnetic metals with other lightweight carbon materials is an effective solution. In this work, magnetic nanoparticle fiber composites were prepared by electrostatic spinning and high-temperature annealing processes. By adjusting the preparation process and annealing temperature, Co/Co7Fe3/CF-800 fiber composites containing double-shell hollow structured nanocubes were cleverly synthesized. The material is mixed with paraffin wax and has a minimum reflection loss (RL) of –52.14 dB and a maximum effective absorption bandwidth (EAB) of 6.16 GHz at a load of 10 wt%. By analyzing the electromagnetic parameters of the material, it was demonstrated that the material absorbs EMW through the synergistic effect of dielectric and magnetic losses. Electrochemical testing in a simulated seawater environment demonstrated that the material also has a degree of self-anticorrosion capability. This work provides new strategies for designing materials with excellent electromagnetic wave absorption and self-anticorrosion properties.
{"title":"“Two birds one stone” strategy to integrate electromagnetic wave absorption and self-anticorrosion in magnetic nanocomposites with double-shell hollow structure","authors":"Zhiqiang Guo, Di Lan, Chuanhui Zhang, Zhenguo Gao, Muyi Han, Xuetao Shi, Mukun He, Hua Guo, Zirui Jia, Guanglei Wu","doi":"10.1016/j.jmst.2024.09.020","DOIUrl":"https://doi.org/10.1016/j.jmst.2024.09.020","url":null,"abstract":"Magnetic metal has broad application prospects in the field of electromagnetic wave (EMW) absorption due to its excellent dielectric and magnetic properties. However, high density and poor chemical stability constrain their development potential. The combination of magnetic metals with other lightweight carbon materials is an effective solution. In this work, magnetic nanoparticle fiber composites were prepared by electrostatic spinning and high-temperature annealing processes. By adjusting the preparation process and annealing temperature, Co/Co<sub>7</sub>Fe<sub>3</sub>/CF-800 fiber composites containing double-shell hollow structured nanocubes were cleverly synthesized. The material is mixed with paraffin wax and has a minimum reflection loss (RL) of –52.14 dB and a maximum effective absorption bandwidth (EAB) of 6.16 GHz at a load of 10 wt%. By analyzing the electromagnetic parameters of the material, it was demonstrated that the material absorbs EMW through the synergistic effect of dielectric and magnetic losses. Electrochemical testing in a simulated seawater environment demonstrated that the material also has a degree of self-anticorrosion capability. This work provides new strategies for designing materials with excellent electromagnetic wave absorption and self-anticorrosion properties.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"38 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360102","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}
Pub Date : 2024-09-30DOI: 10.1016/j.jmst.2024.09.016
Shanchi Wang, Zhiguang Xu, Juan Zhang, Fang Guo, Zhenzhen Wei, Tao Zhang, Yan Zhao
The effective thermal management of lithium-ion batteries is the key to ensuring their fast charging-discharging, safe and efficient operation. Herein, inspired by transpiration-driven water transport in plants, we report a highly hygroscopic needle-punched carbon fiber felt (HS/CFF) with high evaporative cooling efficiency and fire resistance for the safe operation of lithium-ion batteries working at ultrahigh-rate conditions. The three-dimensional fiber skeleton structure constructed by needle punching in the carbon fiber felt enables effective water transport and storage in HS/CFF, without any water leakage. At an ultra-high discharge rate of 10 C, HS/CFF can reduce the maximum temperature of commercial lithium-ion batteries by 18 °C, and can keep the battery temperature below 60 °C. During 500 cycles of charge-discharge, HS/CFF maintains stable evaporative heat dissipation performance, which helps to improve the safety of lithium-ion batteries and extend their service life. Moreover, HS/CFF remains non-combustible even under exposure to a flame (600-700 °C) for 10 min, and the HS/CFF can be reused after the burning test, with the original excellent heat dissipation effect unchanged. This flexible, fire-resistant cooling material offers a promising avenue for low-energy intelligent thermal management of lithium-ion batteries and other heat-generating electronic devices.
锂离子电池的有效热管理是确保其快速充放电、安全高效运行的关键。在此，我们受植物蒸腾作用驱动的水分传输的启发，报告了一种具有高蒸发冷却效率和防火性能的高吸湿性针刺碳纤维毡（HS/CFF），用于锂离子电池在超高速条件下的安全运行。通过针刺碳纤维毡构建的三维纤维骨架结构可实现 HS/CFF 的有效水分传输和存储，且不会出现任何漏水现象。在 10 C 的超高放电率条件下，HS/CFF 可将商用锂离子电池的最高温度降低 18 °C，并可将电池温度控制在 60 °C 以下。在 500 次充放电循环过程中，HS/CFF 仍能保持稳定的蒸发散热性能，有助于提高锂离子电池的安全性并延长其使用寿命。此外，HS/CFF 即使暴露在火焰（600-700 °C）中 10 分钟也不会燃烧，并且在燃烧测试后可重复使用，原有的出色散热效果保持不变。这种柔性阻燃冷却材料为锂离子电池和其他发热电子设备的低能耗智能热管理提供了一条前景广阔的途径。
{"title":"Highly hygroscopic needle-punched carbon fiber felt with high evaporative cooling efficiency and fire resistance for safe operation of ultrahigh-rate lithium-ion batteries","authors":"Shanchi Wang, Zhiguang Xu, Juan Zhang, Fang Guo, Zhenzhen Wei, Tao Zhang, Yan Zhao","doi":"10.1016/j.jmst.2024.09.016","DOIUrl":"https://doi.org/10.1016/j.jmst.2024.09.016","url":null,"abstract":"The effective thermal management of lithium-ion batteries is the key to ensuring their fast charging-discharging, safe and efficient operation. Herein, inspired by transpiration-driven water transport in plants, we report a highly hygroscopic needle-punched carbon fiber felt (HS/CFF) with high evaporative cooling efficiency and fire resistance for the safe operation of lithium-ion batteries working at ultrahigh-rate conditions. The three-dimensional fiber skeleton structure constructed by needle punching in the carbon fiber felt enables effective water transport and storage in HS/CFF, without any water leakage. At an ultra-high discharge rate of 10 C, HS/CFF can reduce the maximum temperature of commercial lithium-ion batteries by 18 °C, and can keep the battery temperature below 60 °C. During 500 cycles of charge-discharge, HS/CFF maintains stable evaporative heat dissipation performance, which helps to improve the safety of lithium-ion batteries and extend their service life. Moreover, HS/CFF remains non-combustible even under exposure to a flame (600-700 °C) for 10 min, and the HS/CFF can be reused after the burning test, with the original excellent heat dissipation effect unchanged. This flexible, fire-resistant cooling material offers a promising avenue for low-energy intelligent thermal management of lithium-ion batteries and other heat-generating electronic devices.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"22 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360106","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}
Carbon nanotubes are uniquely featured by the nanoscale tubular structure with a highly-curved surface and defined chirality. The diameter and chirality fundamentally determine their stability and electrical and thermal properties. Up to now, the relationship between the intrinsic thermal conductivity and the atomic features of CNTs has not been established, due to the challenges in precise measurements and characterizations. In this work, we develop a micro electro-thermal device enabling simultaneous thermal measurements by Raman spectroscopy and atomic structural characterization by transmission electron microscopy for individual CNTs. The influence of diameter and chirality is systematically investigated. In addition, the temperature dependence of the thermal conductivity was extracted from parameter optimization of finite-element modeling. It is found that the thermal transport of CNTs depends mainly on the diameter, while the chiral angle has no significant influence. Along with increasing diameter, the room temperature thermal conductivity increases and eventually approaches the limit of flat graphene.
{"title":"Diameter-dependent thermal conductivity of carbon nanotubes","authors":"Hai-Bo Zhao, Dai-Ming Tang, Lili Zhang, Meng-Ke Zou, Rui-Hong Xie, Chang Liu, Hui-Ming Cheng","doi":"10.1016/j.jmst.2024.09.019","DOIUrl":"https://doi.org/10.1016/j.jmst.2024.09.019","url":null,"abstract":"Carbon nanotubes are uniquely featured by the nanoscale tubular structure with a highly-curved surface and defined chirality. The diameter and chirality fundamentally determine their stability and electrical and thermal properties. Up to now, the relationship between the intrinsic thermal conductivity and the atomic features of CNTs has not been established, due to the challenges in precise measurements and characterizations. In this work, we develop a micro electro-thermal device enabling simultaneous thermal measurements by Raman spectroscopy and atomic structural characterization by transmission electron microscopy for individual CNTs. The influence of diameter and chirality is systematically investigated. In addition, the temperature dependence of the thermal conductivity was extracted from parameter optimization of finite-element modeling. It is found that the thermal transport of CNTs depends mainly on the diameter, while the chiral angle has no significant influence. Along with increasing diameter, the room temperature thermal conductivity increases and eventually approaches the limit of flat graphene.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"220 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360103","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}
Pub Date : 2024-09-29DOI: 10.1016/j.jmst.2024.08.065
Chang Liu, Na Wu, Bin Li, Zhou Wang, Lili Wu, Zhihui Zeng, Jiurong Liu
Developing high-efficiency electromagnetic wave (EMW) absorbers by designing dielectric/magnetic components and microstructure in a straightforward, scalable method is highly desirable yet challenging. Here, we introduce a novel hierarchical composite aerogel-based EMW absorber composed of conductive carbon nanotubes (CNTs) and magnetic metal-organic framework (MOF) derivatives, integrated with sustainable cellulose nanofibers (CNF) derived carbon. This composite was prepared using a scalable freeze-casting followed by carbonization approach. Freeze casting enabled the creation of porous monoliths with high specific surface areas and customizable pore sizes and porosities, crucial for enhancing EMW reflection and scattering. Carbonization enhanced composite conductivity and stabilized the cobalt (Co)/carbon nanoparticles derived from ZIF-67 within the carbon matrix. CNF-derived carbon facilitated the efficient integration of ZIF-derived Co nanoparticles and CNTs, resulting in a robust 3D aerogel structure. The synergistic effects of CNT conductive paths and Co nanoparticles' magnetic losses provided an efficient route to enhance EMW absorption. Moreover, the creation of numerous heterogeneous interfaces augmented polarization losses, significantly enhancing EMW loss capability. Remarkably, the composite achieved outstanding EMW absorption, with a minimum reflection loss of -71.03 dB at a filling ratio of merely 10 wt.% and an effective absorption bandwidth of 4.64 GHz, comparable to leading EMW absorbers reported to date.
通过直接、可扩展的方法设计介电/磁性成分和微结构来开发高效电磁波（EMW）吸收器是非常理想的，但也是极具挑战性的。在此，我们介绍一种新型分层复合气凝胶电磁波吸收器，它由导电碳纳米管（CNT）和磁性金属有机框架（MOF）衍生物组成，并与可持续纤维素纳米纤维（CNF）衍生碳集成。这种复合材料的制备采用了可扩展的先冷冻铸造后碳化的方法。冷冻铸造法能够制造出具有高比表面积、可定制孔径大小和孔隙率的多孔单片，这对增强电磁波的反射和散射至关重要。碳化增强了复合材料的导电性，并将源自 ZIF-67 的钴（Co）/碳纳米粒子稳定在碳基质中。CNF 衍生的碳促进了 ZIF 衍生的钴纳米粒子和碳纳米管的有效整合，从而形成了坚固的三维气凝胶结构。CNT 导电路径和 Co 纳米粒子磁损的协同效应为增强电磁波吸收提供了有效途径。此外，大量异质界面的形成增加了极化损耗，显著提高了电磁波损耗能力。值得注意的是，该复合材料实现了出色的电磁波吸收能力，在填充率仅为 10 wt.% 的情况下，最小反射损耗为 -71.03 dB，有效吸收带宽为 4.64 GHz，与迄今报道的主要电磁波吸收器相当。
{"title":"Facile manufacturing of carbon nanotube/ZIF-67-derived cobalt composite aerogel with high-efficiency electromagnetic wave absorption","authors":"Chang Liu, Na Wu, Bin Li, Zhou Wang, Lili Wu, Zhihui Zeng, Jiurong Liu","doi":"10.1016/j.jmst.2024.08.065","DOIUrl":"https://doi.org/10.1016/j.jmst.2024.08.065","url":null,"abstract":"Developing high-efficiency electromagnetic wave (EMW) absorbers by designing dielectric/magnetic components and microstructure in a straightforward, scalable method is highly desirable yet challenging. Here, we introduce a novel hierarchical composite aerogel-based EMW absorber composed of conductive carbon nanotubes (CNTs) and magnetic metal-organic framework (MOF) derivatives, integrated with sustainable cellulose nanofibers (CNF) derived carbon. This composite was prepared using a scalable freeze-casting followed by carbonization approach. Freeze casting enabled the creation of porous monoliths with high specific surface areas and customizable pore sizes and porosities, crucial for enhancing EMW reflection and scattering. Carbonization enhanced composite conductivity and stabilized the cobalt (Co)/carbon nanoparticles derived from ZIF-67 within the carbon matrix. CNF-derived carbon facilitated the efficient integration of ZIF-derived Co nanoparticles and CNTs, resulting in a robust 3D aerogel structure. The synergistic effects of CNT conductive paths and Co nanoparticles' magnetic losses provided an efficient route to enhance EMW absorption. Moreover, the creation of numerous heterogeneous interfaces augmented polarization losses, significantly enhancing EMW loss capability. Remarkably, the composite achieved outstanding EMW absorption, with a minimum reflection loss of -71.03 dB at a filling ratio of merely 10 wt.% and an effective absorption bandwidth of 4.64 GHz, comparable to leading EMW absorbers reported to date.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"10 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330053","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}
Pub Date : 2024-09-28DOI: 10.1016/j.jmst.2024.08.063
Jianxi Liu, Yifan Fang, Yang Ou, Xiaowei Shi, Yaoming Zhang, Qiang Chen, Lei Li, Feng Zhou, Weimin Liu
The synergy between corrosion protection and wear resistance is an effective strategy for the development of multifunctional coating to withstand complex working conditions. This study reports an epoxy resin coating filled with benzotriazole loaded metal-organic frameworks (BTA-MOFs) functionalized graphene oxide nanoribbons (GONR) that exhibit active anti-corrosion, act as a barrier to corrosive ion, and enhance wear resistance. The GONR@BTA-MOFs composite is synthesized through chemically etching multi-walled carbon nanotubes and subsequent electrostatic self-assembly corrosion inhibitors loaded MOFs onto the GONR. The composite demonstrates improved compatibility with epoxy resins compared to carbon nanotubes. The anti-corrosion performance of the composite coating is investigated using electrochemical impedance spectroscopy. After immersing in a 3.5 wt.% NaCl solution for 25 d, the alternating current impedance of the composite coating is three orders of magnitude higher than that of pure epoxy resin. Simultaneously, the controlled release of the corrosion inhibitor retards the deterioration of the coating after localized damage occurrence, which functions as active corrosion protection. The GONR@BTA-MOFs/EP composite coating exhibits the highest corrosion potential of -0.188 V and the lowest corrosion current of 3.162 × 10−9 A cm−2) in the Tafel test. Tribological studies reveal a reduction in the friction coefficient from 0.62 to 0.08 after incorporating GONR@BTA-MOFs in the coating, with the wear volume being seven times lower than that of pure epoxy resin. The excellent lubrication effect of the nanomaterials reduces the coefficient of friction of the coating, thereby improving the abrasion resistance of the coating. The synergy between the self-lubrication of the two-dimensional layered fillers and the corrosion resistance of the smart inhibitor containers suggests a promising strategy for enhancing the performance of epoxy resins under complex working conditions.
{"title":"Synergistic anti-corrosion and anti-wear of epoxy coating functionalized with inhibitor-loaded graphene oxide nanoribbons","authors":"Jianxi Liu, Yifan Fang, Yang Ou, Xiaowei Shi, Yaoming Zhang, Qiang Chen, Lei Li, Feng Zhou, Weimin Liu","doi":"10.1016/j.jmst.2024.08.063","DOIUrl":"https://doi.org/10.1016/j.jmst.2024.08.063","url":null,"abstract":"The synergy between corrosion protection and wear resistance is an effective strategy for the development of multifunctional coating to withstand complex working conditions. This study reports an epoxy resin coating filled with benzotriazole loaded metal-organic frameworks (BTA-MOFs) functionalized graphene oxide nanoribbons (GONR) that exhibit active anti-corrosion, act as a barrier to corrosive ion, and enhance wear resistance. The GONR@BTA-MOFs composite is synthesized through chemically etching multi-walled carbon nanotubes and subsequent electrostatic self-assembly corrosion inhibitors loaded MOFs onto the GONR. The composite demonstrates improved compatibility with epoxy resins compared to carbon nanotubes. The anti-corrosion performance of the composite coating is investigated using electrochemical impedance spectroscopy. After immersing in a 3.5 wt.% NaCl solution for 25 d, the alternating current impedance of the composite coating is three orders of magnitude higher than that of pure epoxy resin. Simultaneously, the controlled release of the corrosion inhibitor retards the deterioration of the coating after localized damage occurrence, which functions as active corrosion protection. The GONR@BTA-MOFs/EP composite coating exhibits the highest corrosion potential of -0.188 V and the lowest corrosion current of 3.162 × 10<sup>−9</sup> A cm<sup>−2</sup>) in the Tafel test. Tribological studies reveal a reduction in the friction coefficient from 0.62 to 0.08 after incorporating GONR@BTA-MOFs in the coating, with the wear volume being seven times lower than that of pure epoxy resin. The excellent lubrication effect of the nanomaterials reduces the coefficient of friction of the coating, thereby improving the abrasion resistance of the coating. The synergy between the self-lubrication of the two-dimensional layered fillers and the corrosion resistance of the smart inhibitor containers suggests a promising strategy for enhancing the performance of epoxy resins under complex working conditions.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"218 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142329276","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}
Pub Date : 2024-09-28DOI: 10.1016/j.jmst.2024.09.014
Shuang Liu, Lina Li, Tao Yang, Enhui Wang, Xiangtao Yu, Yanglong Hou, Zhentao Du, Sheng Cao, Kuo-Chih Chou, Xinmei Hou
Metal-organic frameworks (MOFs) have caused extensive attention attributed to their widespread applications including electrocatalysis by virtue of their distinctive structural characteristics. However, the direct application of pristine MOFs as bifunctional electrocatalysts is quite challenging due to their insufficient active sites and poor electrical conductivity. In this research, the ultrathin tri-metal (Fe, Co, and V) doped FeCoV-NiMOF nanosheet arrays were prepared through a facile hydrothermal method. Benefiting from the distinctive ultrathin (1.5 nm) nanosheet arrays and electronic structure reconfiguration induced by heteroatom doping, the prepared FeCoV-NiMOF displays the low overpotentials of 238, 309, and 408 mV for oxygen evolution reaction (OER) and 144, 255, and 349 mV for hydrogen evolution reaction (HER) at the current densities of 10, 100, and 1000 mA cm−2, respectively, outperforming the vast majority of previously reported bifunctional pristine MOFs. The electrolytic cell utilizing FeCoV-NiMOF as both cathode and anode requires just 1.61 V to attain 10 mA cm−2 and displays superior stability of 100 h at 100 mA cm−2. In the anion exchange membrane electrolyzer, as-prepared FeCoV-NiMOF needs a low cell voltage of 2.16 V at 500 mA cm−2 for effective overall water splitting, demonstrating its substantial potential as bifunctional electrodes for H2 production. The viable and efficient strategy in this study exhibits great prospects to enrich the exploration of bifunctional MOF-based electrocatalysts with superior performance for renewable energy conversion.
金属有机框架（MOFs）因其独特的结构特征而被广泛应用于电催化等领域，从而引起了广泛关注。然而，由于原始 MOFs 的活性位点不足且导电性差，将其直接用作双功能电催化剂具有相当大的挑战性。本研究采用简便的水热法制备了超薄三金属（铁、钴和钒）掺杂 FeCoV-NiMOF 纳米片阵列。得益于独特的超薄（1.5 nm）纳米片阵列和杂原子掺杂引起的电子结构重构，所制备的 FeCoV-NiMOF 在电流密度为 10、100 和 1000 mA cm-2 时，氧进化反应（OER）的过电位分别为 238、309 和 408 mV，氢进化反应（HER）的过电位分别为 144、255 和 349 mV，优于之前报道的绝大多数双功能原始 MOF。将 FeCoV-NiMOF 同时用作阴极和阳极的电解池只需要 1.61 V 的电压就能达到 10 mA cm-2 的电流密度，并且在 100 mA cm-2 的电流密度下能保持 100 小时的卓越稳定性。在阴离子交换膜电解槽中，制备的 FeCoV-NiMOF 在 500 mA cm-2 的条件下只需 2.16 V 的低电池电压即可实现有效的整体水分离，这证明了其作为双功能电极生产 H2 的巨大潜力。本研究中可行而高效的策略为探索性能优越的双功能 MOF 基电催化剂提供了广阔的前景，可用于可再生能源的转换。
{"title":"Enhanced overall water splitting by morphology and electronic structure engineering on pristine ultrathin metal-organic frameworks","authors":"Shuang Liu, Lina Li, Tao Yang, Enhui Wang, Xiangtao Yu, Yanglong Hou, Zhentao Du, Sheng Cao, Kuo-Chih Chou, Xinmei Hou","doi":"10.1016/j.jmst.2024.09.014","DOIUrl":"https://doi.org/10.1016/j.jmst.2024.09.014","url":null,"abstract":"Metal-organic frameworks (MOFs) have caused extensive attention attributed to their widespread applications including electrocatalysis by virtue of their distinctive structural characteristics. However, the direct application of pristine MOFs as bifunctional electrocatalysts is quite challenging due to their insufficient active sites and poor electrical conductivity. In this research, the ultrathin tri-metal (Fe, Co, and V) doped FeCoV-NiMOF nanosheet arrays were prepared through a facile hydrothermal method. Benefiting from the distinctive ultrathin (1.5 nm) nanosheet arrays and electronic structure reconfiguration induced by heteroatom doping, the prepared FeCoV-NiMOF displays the low overpotentials of 238, 309, and 408 mV for oxygen evolution reaction (OER) and 144, 255, and 349 mV for hydrogen evolution reaction (HER) at the current densities of 10, 100, and 1000 mA cm<sup>−2</sup>, respectively, outperforming the vast majority of previously reported bifunctional pristine MOFs. The electrolytic cell utilizing FeCoV-NiMOF as both cathode and anode requires just 1.61 V to attain 10 mA cm<sup>−2</sup> and displays superior stability of 100 h at 100 mA cm<sup>−2</sup>. In the anion exchange membrane electrolyzer, as-prepared FeCoV-NiMOF needs a low cell voltage of 2.16 V at 500 mA cm<sup>−2</sup> for effective overall water splitting, demonstrating its substantial potential as bifunctional electrodes for H<sub>2</sub> production. The viable and efficient strategy in this study exhibits great prospects to enrich the exploration of bifunctional MOF-based electrocatalysts with superior performance for renewable energy conversion.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"54 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142329181","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}
Pub Date : 2024-09-28DOI: 10.1016/j.jmst.2024.08.064
Sisi Tang, Li Li, Jinlong Su, Yuan Yuan, Yong Han, Jinglian Fan
Titanium-silicon (Ti-Si) alloy system shows significant potential for aerospace and automotive applications due to its superior specific strength, creep resistance, and oxidation resistance. For Si-containing Ti alloys, the sufficient content of Si is critical for achieving these favorable performances, while excessive Si addition will result in mechanical brittleness. Herein, both physical experiments and finite element (FE) simulations are employed to investigate the micro-mechanisms of Si alloying in tailoring the mechanical properties of Ti alloys. Four typical states of Si-containing Ti alloys (solid solution state, hypoeutectoid state, near-eutectoid state, hypereutectoid state) with varying Si content (0.3–1.2 wt.%) were fabricated via in-situ alloying spark plasma sintering. Experimental results indicate that in-situ alloying of 0.6 wt.% Si enhances the alloy's strength and ductility simultaneously due to the formation of fine and uniformly dispersed Ti5Si3 particles, while higher content of Si (0.9 and 1.2 wt.%) results in coarser primary Ti5Si3 agglomerations, deteriorating the ductility. FE simulations support these findings, highlighting the finer and more uniformly distributed Ti5Si3 particles contribute to less stress concentration and promote uniform deformation across the matrix, while agglomerated Ti5Si3 particles result in increased local stress concentrations, leading to higher chances of particle fracture and reduced ductility. This study not only elucidates the micro-mechanisms of in-situ Si alloying for tailoring the mechanical properties of Ti alloys but also aids in optimizing the design of high-performance Ti alloys.
钛-硅（Ti-Si）合金系统因其卓越的比强度、抗蠕变性和抗氧化性，在航空航天和汽车应用中显示出巨大的潜力。对于含硅的钛合金而言，足够的硅含量是实现这些良好性能的关键，而过量的硅添加则会导致机械脆性。本文采用物理实验和有限元（FE）模拟来研究硅合金化在定制钛合金机械性能方面的微观机制。通过原位合金化火花等离子烧结制造了四种典型的含硅钛合金状态（固溶态、低共晶态、近共晶态和超共晶态），其中硅的含量各不相同（0.3-1.2 wt.%）。实验结果表明，原位合金化 0.6 重量百分比的 Si 会形成细小且均匀分散的 Ti5Si3 颗粒，从而同时提高合金的强度和延展性；而更高的 Si 含量（0.9 和 1.2 重量百分比）会导致更粗大的原生 Ti5Si3 团聚，从而降低延展性。有限元模拟支持这些发现，突出表明更细、分布更均匀的 Ti5Si3 颗粒有助于减少应力集中并促进整个基体的均匀变形，而团聚的 Ti5Si3 颗粒会导致局部应力集中增加，从而导致颗粒断裂的几率增加和延展性降低。这项研究不仅阐明了原位 Si 合金用于定制钛合金机械性能的微观机制，还有助于优化高性能钛合金的设计。
{"title":"Unveiling micro-scale mechanisms of in-situ silicon alloying for tailoring mechanical properties in titanium alloys: Experiments and computational modeling","authors":"Sisi Tang, Li Li, Jinlong Su, Yuan Yuan, Yong Han, Jinglian Fan","doi":"10.1016/j.jmst.2024.08.064","DOIUrl":"https://doi.org/10.1016/j.jmst.2024.08.064","url":null,"abstract":"Titanium-silicon (Ti-Si) alloy system shows significant potential for aerospace and automotive applications due to its superior specific strength, creep resistance, and oxidation resistance. For Si-containing Ti alloys, the sufficient content of Si is critical for achieving these favorable performances, while excessive Si addition will result in mechanical brittleness. Herein, both physical experiments and finite element (FE) simulations are employed to investigate the micro-mechanisms of Si alloying in tailoring the mechanical properties of Ti alloys. Four typical states of Si-containing Ti alloys (solid solution state, hypoeutectoid state, near-eutectoid state, hypereutectoid state) with varying Si content (0.3–1.2 wt.%) were fabricated via in-situ alloying spark plasma sintering. Experimental results indicate that in-situ alloying of 0.6 wt.% Si enhances the alloy's strength and ductility simultaneously due to the formation of fine and uniformly dispersed Ti<sub>5</sub>Si<sub>3</sub> particles, while higher content of Si (0.9 and 1.2 wt.%) results in coarser primary Ti<sub>5</sub>Si<sub>3</sub> agglomerations, deteriorating the ductility. FE simulations support these findings, highlighting the finer and more uniformly distributed Ti<sub>5</sub>Si<sub>3</sub> particles contribute to less stress concentration and promote uniform deformation across the matrix, while agglomerated Ti<sub>5</sub>Si<sub>3</sub> particles result in increased local stress concentrations, leading to higher chances of particle fracture and reduced ductility. This study not only elucidates the micro-mechanisms of in-situ Si alloying for tailoring the mechanical properties of Ti alloys but also aids in optimizing the design of high-performance Ti alloys.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"25 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142329272","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}
Conversion electrodes typically have high theoretical specific capacity, but mostly suffer large structural changes during charge/discharge and result in poor cycling stability. The optimization of the polycrystalline materials is the mostly used strategy, however, these polycrystalline materials are intrinsically vulnerable to grain-boundary (intergranular) fracture caused by the anisotropic volume change during sodiation/desodiation, resulting in rapid impedance growth and capacity decay. Herein, we propose an alternative pathway to design single-crystal materials as potential conversion anodes. As an example, SnO2 with different crystallinities is successfully synthesized via solvothermal methods and compared to determine the implications of different crystallinity for the electrochemical properties of conversion anodes. It is demonstrated that the single-crystal SnO2 not only has faster Na+ diffusion dynamics but also maintains structural stability via topotactic reaction. Further optimization of the electron conduction and structural robustness is realized by uniformly covering a graphitic carbon shell on the surface of single-crystal SnO2 nanosheets. The modified single-crystal SnO2 exhibits a high reversible capacity of 436.2 mA h g–1 and maintains a high capacity of 257.1 mA h g-1 and remarkable capacity retention of about 98.9% after 9000 cycles at 5000 mA g-1. The deep understandings of the topotactic reaction in single crystal conversion anode in this work provide a theoretical foundation and new direction for further developing electrode materials with excellent electrochemical performance, especially high rate capabilities, and long cyclability.
转换电极通常具有较高的理论比容量，但在充放电过程中大多会发生较大的结构变化，导致循环稳定性较差。多晶材料的优化是最常用的策略，然而，这些多晶材料在钠化/解钠过程中由于各向异性的体积变化而导致晶界（晶粒间）断裂，从而导致阻抗快速增长和容量衰减。在此，我们提出了设计单晶材料作为潜在转换阳极的另一种途径。例如，我们通过溶热法成功合成了不同结晶度的二氧化锡，并对其进行了比较，以确定不同结晶度对转换阳极电化学特性的影响。结果表明，单晶 SnO2 不仅具有更快的 Na+ 扩散动力学，还能通过拓扑反应保持结构的稳定性。通过在单晶二氧化锡纳米片表面均匀地覆盖一层石墨碳壳，进一步优化了电子传导和结构的稳健性。改性后的单晶二氧化锡显示出 436.2 mA h g-1 的高可逆容量，并在 5000 mA g-1 下循环 9000 次后保持 257.1 mA h g-1 的高容量和约 98.9% 的显著容量保持率。这项工作对单晶转换阳极中拓扑反应的深入理解为进一步开发具有优异电化学性能，尤其是高倍率能力和长循环能力的电极材料提供了理论基础和新的方向。
{"title":"Fast diffusion and stable topotactic reaction in single crystal conversion anode","authors":"Weili Liu, Tian Xu, Shouguo Wang, Guanglin Xia, Dalin Sun, Xuebin Yu","doi":"10.1016/j.jmst.2024.09.013","DOIUrl":"https://doi.org/10.1016/j.jmst.2024.09.013","url":null,"abstract":"Conversion electrodes typically have high theoretical specific capacity, but mostly suffer large structural changes during charge/discharge and result in poor cycling stability. The optimization of the polycrystalline materials is the mostly used strategy, however, these polycrystalline materials are intrinsically vulnerable to grain-boundary (intergranular) fracture caused by the anisotropic volume change during sodiation/desodiation, resulting in rapid impedance growth and capacity decay. Herein, we propose an alternative pathway to design single-crystal materials as potential conversion anodes. As an example, SnO<sub>2</sub> with different crystallinities is successfully synthesized via solvothermal methods and compared to determine the implications of different crystallinity for the electrochemical properties of conversion anodes. It is demonstrated that the single-crystal SnO<sub>2</sub> not only has faster Na<sup>+</sup> diffusion dynamics but also maintains structural stability via topotactic reaction. Further optimization of the electron conduction and structural robustness is realized by uniformly covering a graphitic carbon shell on the surface of single-crystal SnO<sub>2</sub> nanosheets. The modified single-crystal SnO<sub>2</sub> exhibits a high reversible capacity of 436.2 mA h g<sup>–1</sup> and maintains a high capacity of 257.1 mA h g<sup>-1</sup> and remarkable capacity retention of about 98.9% after 9000 cycles at 5000 mA g<sup>-1</sup>. The deep understandings of the topotactic reaction in single crystal conversion anode in this work provide a theoretical foundation and new direction for further developing electrode materials with excellent electrochemical performance, especially high rate capabilities, and long cyclability.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"27 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325618","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}
Pub Date : 2024-09-26DOI: 10.1016/j.jmst.2024.09.008
Evan Ma, Jun Ding
The recently emerging multi-principal element alloys (MPEAs) are attracting widespread attention. This naturally raises a materials science question as to what is new in the microstructure of these “high-entropy” alloys (HEAs) that makes them different from well-documented traditional (dilute) solid solutions. Here we illustrate that the concentrated chemical make-up towards equi-molar compositions in these multi-principal element solid solutions MPEA brings forth an unusually high population density of chemical inhomogeneities at length scales from sub-nanometers to a few nanometers. Specifically, a spatial variation in local composition, and in local chemical order (LCO), constitutes an inherent structural feature. In this article we define these various inhomogeneities and discuss the challenges facing their identification while explaining their relations with, and (sometimes subtle) differences from, the previously known inhomogeneities including the compositional coring in cast ingots, chemical short-range order and (precursor of) precipitates in conventional solid solutions. The potential impact is discussed in an outlook at the end, to provide a future perspective on this sub-field.
{"title":"Compositional fluctuation and local chemical ordering in multi-principal element alloys","authors":"Evan Ma, Jun Ding","doi":"10.1016/j.jmst.2024.09.008","DOIUrl":"https://doi.org/10.1016/j.jmst.2024.09.008","url":null,"abstract":"The recently emerging multi-principal element alloys (MPEAs) are attracting widespread attention. This naturally raises a materials science question as to what is new in the microstructure of these “high-entropy” alloys (HEAs) that makes them different from well-documented traditional (dilute) solid solutions. Here we illustrate that the concentrated chemical make-up towards equi-molar compositions in these multi-principal element solid solutions MPEA brings forth an unusually high population density of chemical inhomogeneities at length scales from sub-nanometers to a few nanometers. Specifically, a spatial variation in local composition, and in local chemical order (LCO), constitutes an inherent structural feature. In this article we define these various inhomogeneities and discuss the challenges facing their identification while explaining their relations with, and (sometimes subtle) differences from, the previously known inhomogeneities including the compositional coring in cast ingots, chemical short-range order and (precursor of) precipitates in conventional solid solutions. The potential impact is discussed in an outlook at the end, to provide a future perspective on this sub-field.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"25 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142321390","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}
Pub Date : 2024-09-26DOI: 10.1016/j.jmst.2024.08.057
Peng He, Meiqian Fu, Fangqian Wang, Yushan Zhang, Chen Li, Jiening Feng, Lianwen Deng, Jun Yan
Multifunctional compatible stealth materials have emerged as the focal point of contemporary protection technology research and vanadium-based nanomaterials play a pivotal role in the development of advanced stealth materials. Here, a compatible stealth aerogel is successfully synthesized by employing mixed-valence decavanadate as the vanadium oxide (VOx) molecular model. Ultralight {VⅣVV9}/MXene aerogel (0.0429 g cm–3) exhibits exceptional radar stealth performance with a minimal reflection loss (RLmin) of −57.74 dB (99.9998% EMW absorption) and a significantly superior radar cross section reduction value of 26.77 dB m2. The aerogel's exceptional properties, including a low infrared (IR) emissivity (0.479) and a low thermal conductivity of (32.30 mW m–1 K–1), are crucial for enabling compatibility with IR and thermal stealth technologies. The presence of a mixed-valence polyoxovanadate cluster leads to an increase in the Schottky barrier and enhances magnetic properties, consequently boosting interfacial polarization and contributing to magnetic losses during electromagnetic wave (EMW) absorption. Consequently, altering the number of valence electrons significantly enhances the compatible stealth capabilities. These findings contribute significantly to our comprehension of how microstructure impacts EMW absorption processes and provide a basis for further research into the development of VOx-based compatible stealth materials.
多功能兼容隐形材料已成为当代防护技术研究的焦点，而钒基纳米材料在先进隐形材料的开发中起着举足轻重的作用。本文采用混合价癸钒酸盐作为氧化钒（VOx）分子模型，成功合成了一种兼容隐身气凝胶。超轻型{VⅣVV9}/MXene气凝胶（0.0429 g cm-3）具有卓越的雷达隐身性能，其最小反射损耗（RLmin）为-57.74 dB（99.9998%的电磁波吸收），雷达截面减小值为26.77 dB m2。气凝胶的特殊性能，包括低红外（IR）发射率（0.479）和低导热率（32.30 mW m-1 K-1），对于兼容红外和热隐身技术至关重要。混价多氧钒酸盐团簇的存在会增加肖特基势垒并增强磁性，从而提高界面极化，并导致电磁波（EMW）吸收过程中的磁损耗。因此，改变价电子的数量可显著增强兼容的隐身能力。这些发现极大地促进了我们对微观结构如何影响电磁波吸收过程的理解，并为进一步研究开发基于 VOx 的兼容隐形材料奠定了基础。
{"title":"Unlocking versatile capabilities: Mixed-valence decavanadate aerogels for boosting radar, infrared, and thermal stealth","authors":"Peng He, Meiqian Fu, Fangqian Wang, Yushan Zhang, Chen Li, Jiening Feng, Lianwen Deng, Jun Yan","doi":"10.1016/j.jmst.2024.08.057","DOIUrl":"https://doi.org/10.1016/j.jmst.2024.08.057","url":null,"abstract":"Multifunctional compatible stealth materials have emerged as the focal point of contemporary protection technology research and vanadium-based nanomaterials play a pivotal role in the development of advanced stealth materials. Here, a compatible stealth aerogel is successfully synthesized by employing mixed-valence decavanadate as the vanadium oxide (VO<em><sub>x</sub></em>) molecular model. Ultralight {V<sup>Ⅳ</sup>V<sup>V</sup><sub>9</sub>}/MXene aerogel (0.0429 g cm<sup>–3</sup>) exhibits exceptional radar stealth performance with a minimal reflection loss (RL<sub>min</sub>) of −57.74 dB (99.9998% EMW absorption) and a significantly superior radar cross section reduction value of 26.77 dB m<sup>2</sup>. The aerogel's exceptional properties, including a low infrared (IR) emissivity (0.479) and a low thermal conductivity of (32.30 mW m<sup>–1</sup> K<sup>–1</sup>), are crucial for enabling compatibility with IR and thermal stealth technologies. The presence of a mixed-valence polyoxovanadate cluster leads to an increase in the Schottky barrier and enhances magnetic properties, consequently boosting interfacial polarization and contributing to magnetic losses during electromagnetic wave (EMW) absorption. Consequently, altering the number of valence electrons significantly enhances the compatible stealth capabilities. These findings contribute significantly to our comprehension of how microstructure impacts EMW absorption processes and provide a basis for further research into the development of VO<em><sub>x</sub></em>-based compatible stealth materials.","PeriodicalId":16154,"journal":{"name":"Journal of Materials Science & Technology","volume":"97 1","pages":""},"PeriodicalIF":10.9,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142324898","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}
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