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Effect of Sc addition on downstream processing of twin-roll cast Al-Cu-Li-Mg-Zr-based alloys

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Transactions of Nonferrous Metals Society of China 2023年

作者： Rostislav Králík Barbora K?ivská Lucia Bajto?ová Mykhailo Stolbchenko Mirko Schaper Olexandr Grydin Miroslav Cieslar University of Paderborn Faculty of Mechanical Engineering department of materials Science Charles University Faculty of Mathematics and physics department of physics of materials

A processing scheme for preparing strips of Al-Cu-Li-Mg-Zr-based alloys microalloyed with Sc is proposed. This scheme includes a twin-roll casting of strips with a near-net-shaped 3 mm gauge and a homogenization/solution treatment processing step. Two twin-roll cast Al-Cu-Li-Mg-Zr-based alloys were studied， one with an addition of 0.17 wt.% Sc. Both alloys were annealed at 300 °C/30 min， 450 °C/30 min， and 530 °C/30 min and quenched into room temperaure water. The first two annealings provide a fine dispersion of Al3Zr/Al3(Sc，Zr) particles. The final annealing step serves as homogenization/solution treatment. A fine crystallization structure of the twin-roll cast materials enables the dissolution of primary particles containing the main alloying elements during relatively short annealing times. Shorter soaking duration limits the depletion of surface layers from Li and significant coarsening of Al3Zr/Al3(Sc，Zr) dispersoids. The Sc-containing material has significantly finer grains already in the as-cast state. The Al3(Sc，Zr) dispersoids formed during the homogenization/solution treatment step prevent grain coarsening at high temperatures. Strengthening θ’ (Al2Cu)， T1(Al2CuLi)， and rare S’ (Al2CuMg) phases form during subsequent artificial aging at 180 °C. The increase in yield strength was 200 MPa in the peak-aged conditions. This value is comparable to the ones reported in similar direct-chill cast materials， thus validating the proposed processing scheme.

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Chalcopyrite solar cells——state-of-the-art and options for improvement

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Science China(physics,Mechanics & Astronomy) 2023年第1期66卷 3-17页

作者： S.Siebentritt T.P.Weiss Laboratory for Photovoltaics Department of Physics and Materials ScienceUniversity of LuxembourgBelvaux 4422Luxembourg

Chalcopyrite solar cells will have to play an important role to mitigate the climate crisis,because of their particularly low carbon emissions.Doping in these semiconductors is due to native defects and intentional alkali impurities.The recent progress in efficiency has been made possible by post-deposition treatments with heavy alkalis.Tail states and band gap distribution are the main limitations for the open circuit voltage in state-of-the-art chalcopyrite solar cells.Further efficiency limitations are due to the increased diode factor because of metastable defect transitions.Alloying with Ag opens new possibilities of band-edge engineering,as well as seems to improve the diode factor.In state-of-the-art cells the back contact is passivated by a Ga gradient;considerable research has been done to passivate the back contact by structured or continuous dielectric layers.A leap forward in efficiency can be expected from tandem cells.Chalcopyrite solar cells show promising potential as bottom cells as well as top cells.

关键词： doping tail states alkali treatment efficiency

Graphene supremacy:the duo duo

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National Science Review 2022年第12期9卷 61-62页

作者： Fan Zhang Xin-Cheng Xie department of physics University of Texas at Dallas International Center for Quantum materials School of Physics Peking University

Graphene is an amazing material that presents us with new challenges and opportunities,even after two decades of extensive study.The two linear energy bands of graphene cross at the K and K’points of the hexagonal Brillouin zone with topological winding numbers±1.This Dirac cone description is nearly perfect within a～3 eV energy range—more than 100 times room temperature.Moreover,the chemistry of graphene sets its Fermi energy right at the Dirac points.

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Second Chern crystals with inherently non-trivial topology

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National Science Review 2023年第8期10卷 148-155页

作者： Xiao-Dong Chen Fu-Long Shi Jian-Wei Liu Ke Shen Xin-Tao He C.T. Chan Wen-Jie Chen Jian-Wen Dong School of physics and State Key Laboratory of Optoelectronic materials and Technologies Sun Yat-sen University department of physics The Hong Kong University of Science and Technology

Chern insulators have been generalized to many classical wave systems and thereby lead to many potential applications such as robust waveguides, quantum computation and high-performance lasers. However, the band structure of a material can be either topologically trivial or non-trivial, depending on how the crystal structure is designed. Here, we propose a second Chern crystal in a four-dimensional parameter space by introducing two extra synthetic translation dimensions. Since the topology of the bulk bands in the synthetic translation space is intrinsically non-trivial, our proposed four-dimensional crystal is guaranteed to be topologically non-trivial regardless of the crystal’s detailed configuration. We derive the topologically protected modes on the lower dimensional boundaries of such a crystal via dimension reduction.Remarkably, we observe the one-dimensional gapless dislocation modes and confirm their robustness in experiments. Our findings provide novel perspectives on topologically non-trivial crystals and may inspire designs of classical wave devices.

关键词： topological photonics synthetic dimension photonic crystals dislocation mode

Liquid-phase sintering enabling mixed ionic-electronic interphases and free-standing composite cathode architecture toward high energy solid-state battery

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Nano Research 2022年第7期15卷 6156-6167页

作者： Xiang Han Weijun Zhou Minfeng Chen Linshan Luo Lanhui Gu Qiaobao Zhang Jizhang Chen Bo Liu Songyan Chen Wenqing Zhang College of materials Science and Engineering Nanjing Forestry UniversityNanjing 210037China department of physics Xiamen UniversityXiamen 361005China College of Mathematics and physics Jinggangshan UniversityJi’an 343009China department of materials Science and Engineering College of MaterialsXiamen 361005China department of physics Southern University of Science and TechnologyShenzhen 518055China

Solid-state batteries(SSBs)will potentially offer increased energy density and,more importantly,improved safety for next generation lithium-ion(Li-ion)batteries.One enabling technology is solid-state composite cathodes with high operating voltage and area capacity.Current composite cathode manufacturing technologies,however,suffer from large interfacial resistance and low active mass loading that with excessive amounts of polymer electrolytes and conductive additives.Here,we report a liquidphase sintering technology that offers mixed ionic-electronic interphases and free-standing electrode architecture design,which eventually contribute to high area capacity.A small amount(~4 wt.%)of lithium hydroxide(LiOH)and boric acid(H_(3)BO_(3))with low melting point are utilized as sintering additives that infiltrate into single-crystal Ni-rich LiNi_(0.8)Mn_(0.1)Co_(0.1)(NMC811)particles at a moderately elevated temperature(~350℃)in a liquid state,which not only enable intimate physical contact but also promote the densification process.In addition,the liquid-phase additives react and transform to ionic-conductive lithium boron oxide,together with the indium tin oxide(ITO)nanoparticle coating,mixed ionic-electronic interphases of composite cathode are successfully fabricated.Furthermore,the liquid-phase sintering performed at high-temperature(~800℃)also enables the fabrication of highly dense and thick composite cathodes with a novel free-standing architecture.The promising performance characteristics of such composite cathodes,for example,delivering an area capacity above 8 mAh·cm^(−2) within a wide voltage window up to 4.4 V,open new opportunities for SSBs with a high energy density of 500 Wh·kg^(−1) for safer portable electronic and electrical transport.

关键词： solid-state battery single-crystal Ni-rich LiNi_(0.8)Mn_(0.1)Co_(0.1) liquid-phase sintering mixed ionic-electronic interphases freestanding architecture

A review on anode materials for lithium/sodium-ion batteries

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能源化学:英文版 2023年第8期83卷 509-540,I0013页

作者： Abhimanyu Kumar Prajapati Ashish Bhatnagar department of physics and materials Science and Engineering Jaypee Institute of Information TechnologyNoida 201309Indid

Since lithium-ion batteries(LIBs) have been substantially researched in recent years, they now possess exceptional energy and power densities, making them the most suited energy storage technology for use in developed and developing industries like stationary storage and electric cars, etc. Concerns about the cost and availability of lithium have prompted research into alternatives, such as sodium-ion batteries(SIBs), which use sodium instead of lithium as the charge carrier. This is especially relevant for stationary applications, where the size and weight of battery are less important. The working efficiency and capacity of these batteries are mainly dependent on the anode, cathode, and electrolyte. The anode,which is one of these components, is by far the most important part of the rechargeable battery.Because of its characteristics and its structure, the anode has a tremendous impact on the overall performance of the battery as a whole. Keeping the above in view, in this review we critically reviewed the different types of anodes and their performances studied to date in LIBs and SIBs. The review article is divided into three main sections, namely:(i) intercalation reaction-based anode materials;(ii) alloying reaction-based anode materials;and(iii) conversion reaction-based anode materials, which are further classified into a number of subsections based on the type of material used. In each main section, we have discussed the merits and challenges faced by their particular system. Afterward, a brief summary of the review has been discussed. Finally, the road ahead for better application of Li/Na-ion batteries is discussed, which seems to mainly depend on exploring the innovative materials as anode and on the inoperando characterization of the existing materials for making them more capable in terms of application in rechargeable batteries.

关键词： Lithium/Sodium-ion batteries Anode materials Nanomaterials Metal-organic framework Conversion materials Intercalated materials Alloying materials

Comparisons between adsorption and diffusion of alkali,alkaline earth metal atoms on silicene and those on silicane:Insight from first-principles calculations

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Chinese physics B 2016年第6期25卷 390-396页

作者：徐波卢欢胜刘波刘刚吴木生欧阳楚英 department of physics Laboratory of Computational Materials PhysicsJiangxi Normal University

The adsorption and diffusion behaviors of alkali and alkaline-earth metal atoms on silicane and silicene are both investigated by using a first-principles method within the frame of density functional theory.Silicane is staler against the metal adatoms than silicene.Hydrogenation makes the adsorption energies of various metal atoms considered in our calculations on silicane significantly lower than those on silicene.Similar diffusion energy barriers of alkali metal atoms on silicane and silicene could be observed.However,the diffusion energy barriers of alkali-earth metal atoms on silicane are essentially lower than those on silicene due to the small structural distortion and weak interaction between metal atoms and silicane substrate.Combining the adsorption energy with the diffusion energy barriers,it is found that the clustering would occur when depositing metal atoms on perfect hydrogenated silicene with relative high coverage.In order to avoid forming a metal cluster,we need to remove the hydrogen atoms from the silicane substrate to achieve the defective silicane.Our results are helpful for understanding the interaction between metal atoms and silicene-based two-dimensional materials.

关键词： first-principles calculations silicene and silicane atom adsorption atom diffusion

physics of electron and lithium-ion transport in electrode materials for Li-ion batteries

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Chinese physics B 2016年第1期25卷 78-87页

作者：吴木生徐波欧阳楚英 department of physics Laboratory of Computational Materials Physics Jiangxi Normal University

The physics of ionic and electrical conduction at electrode materials of lithium-ion batteries （LIBs） are briefly sum marized here, besides, we review the current research on ionic and electrical conduction in electrode material incorporating experimental and simulation studies. Commercial LIBs have been widely used in portable electronic devices and are now developed for large-scale applications in hybrid electric vehicles （HEV） and stationary distributed power stations. However, due to the physical limits of the materials, the overall performance of today＇s LIBs does not meet all the requirements for future applications, and the transport problem has been one of the main barriers to further improvement. The electron and Li-ion transport behaviors are important in determining the rate capacity of LIBs.

关键词： Li-ion diffusion electrical conduction polaron conduction Li-ion batteries

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AB堆叠双层蜂窝晶格中的阻挫铁磁相变

Science Bulletin 2022年第24期67卷 2557-2563,M0004页

作者：王世源王瑶闫少华王聪项秉坷梁可一贺秋实 Kenji Watanabe Takashi Taniguchi 田尚杰雷和畅季威戚扬王熠华 State Key Laboratory of Surface physics and department of physics Fudan UniversityShanghai 200438China department of physics and Beijing Key Laboratory of Opto-electronic Functional materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Research Center for Functional materials National Institute for Materials ScienceTsukuba 305-0044Japan International Center for materials Nanoarchitectonics National Institute for Materials ScienceTsukuba 305-0044Japan Shanghai Research Center for Quantum Sciences Shanghai 201315China

根据Mermin-Wagner定理,磁各向异性是二维体系磁有序的必要条件.而当出现相互竞争的各向异性时,磁相变会变得非同寻常.本文利用了扫描超导量子干涉仪在零场下对磁通的高灵敏度,对从单层到ABC堆叠的块材的CrBr3样品进行了磁化率和磁化强... 详细信息

根据Mermin-Wagner定理,磁各向异性是二维体系磁有序的必要条件.而当出现相互竞争的各向异性时,磁相变会变得非同寻常.本文利用了扫描超导量子干涉仪在零场下对磁通的高灵敏度,对从单层到ABC堆叠的块材的CrBr3样品进行了磁化率和磁化强度的变温成像.研究发现厚层CrBr3在临界温区展现出层间与层内的各向异性竞争所导致的磁化率平台与尖峰.随着样品层数减少,这两个特征逐渐变宽并在双层达到与其临界温度类似大小的温度涨落,而在单层中则是更常规的铁磁相变行为.这表明二维极限下的量子涨落会增强层内与层间的竞争效应,产生类似阻挫的铁磁临界行为.这一结果揭示了一种在AB堆叠的双层蜂窝结构中的阻挫磁相变,并为进一步研究二维材料中的自旋阻挫打下基础.

关键词：超导量子干涉仪铁磁相变磁各向异性阻挫温度涨落磁有序量子涨落磁化率