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Design Strategies for Aqueous Zinc Metal Batteries with High Zinc Utilization: From Metal Anodes to Anode-Free Structures 被引量:1
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作者 Xianfu Zhang Long Zhang +2 位作者 Xinyuan Jia Wen Song Yongchang Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期305-349,共45页
Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low re... Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low redox potential of zinc(Zn) metal. However,several issues such as dendrite formation, hydrogen evolution, corrosion, and passivation of Zn metal anodes cause irreversible loss of the active materials. To solve these issues, researchers often use large amounts of excess Zn to ensure a continuous supply of active materials for Zn anodes. This leads to the ultralow utilization of Zn anodes and squanders the high energy density of AZMBs. Herein, the design strategies for AZMBs with high Zn utilization are discussed in depth, from utilizing thinner Zn foils to constructing anode-free structures with theoretical Zn utilization of 100%, which provides comprehensive guidelines for further research. Representative methods for calculating the depth of discharge of Zn anodes with different structures are first summarized. The reasonable modification strategies of Zn foil anodes, current collectors with pre-deposited Zn, and anode-free aqueous Zn metal batteries(AF-AZMBs) to improve Zn utilization are then detailed. In particular, the working mechanism of AF-AZMBs is systematically introduced. Finally, the challenges and perspectives for constructing high-utilization Zn anodes are presented. 展开更多
关键词 Aqueous zinc metal batteries Zinc anodes High zinc utilization Depth of discharge Anode-free structures
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Recent progress on fabrication, spectroscopy properties, and device applications in Sn-doped CdS micro-nano structures
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作者 Bo Cao Ye Tian +8 位作者 Huan Fei Wen Hao Guo Xiaoyu Wu Liangjie Li Zhenrong Zhang Lai Liu Qiang Zhu Jun Tang Jun Liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第9期7-27,共21页
One-dimensional semiconductor materials possess excellent photoelectric properties and potential for the construction of integrated nanodevices. Among them, Sn-doped CdS has different micro-nano structures, including ... One-dimensional semiconductor materials possess excellent photoelectric properties and potential for the construction of integrated nanodevices. Among them, Sn-doped CdS has different micro-nano structures, including nanoribbons,nanowires, comb-like structures, and superlattices, with rich optical microcavity modes, excellent optical properties, and a wide range of application fields. This article reviews the research progress of various micrometer structures of Sn-doped CdS, systematically elaborates the effects of different growth conditions on the preparation of Sn-doped CdS micro-nano structures, as well as the spectral characteristics of these structures and their potential applications in certain fields. With the continuous progress of nanotechnology, it is expected that Sn-doped CdS micro-nano structures will achieve more breakthroughs in the field of optoelectronics and form cross-integration with other fields, jointly promoting scientific, technological, and social development. 展开更多
关键词 Sn-doped CdS micro-nano structure SUPERLATTICES optical microcavity
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Structural color of metallic glass through picosecond laser
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作者 Yue’e Zhang Xing Tong +3 位作者 Yuqiang Yan Shuo Cao Hai-Bo Ke Wei-Hua Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期120-128,共9页
The alteration in surface color of metallic glasses(MGs)holds great significance in the context of microstructuredesign and commercial utility.It is essential to accurately describe the structures that are formed duri... The alteration in surface color of metallic glasses(MGs)holds great significance in the context of microstructuredesign and commercial utility.It is essential to accurately describe the structures that are formed during the laser and colorseparation processes in order to develop practical laser coloring applications.Due to the high oxidation sensitivity of Labasedmetallic glass,it can broaden the color range but make it more complex.Structure coloring by laser processing on thesurface of La-based metallic glass can be conducted after thermoplastic forming.It is particularly important to clarify therole of structure and composition in the surface coloring process.The aim is to study the relationship between amorphoussurface structural color,surface geometry,and oxide formation by laser processing in metallic glasses.The findings revealedthat the periodic structure primarily determines the surface color at laser energy densities below 1.0 J/mm^(2).In contrast,thesurface color predominantly depends on the proportion of oxides that are formed when energy densities exceed 1.0 J/mm^(2).Consequently,this study provides a novel concept for the fundamental investigation of laser coloring and establishes a newavenue for practical application. 展开更多
关键词 metallic glass picosecond laser periodic structure OXIDES
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Non-flammable long chain phosphate ester based electrolyte via competitive solventized structures for high-performance lithium metal batteries
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作者 Li Liao Zhiqiang Han +16 位作者 Xuanjie Feng Pan Luo Jialin Song Yin Shen Xiaoshuang Luo Xinpeng Li Xuanzhong Wen Bo Yu Junchen Chen Bingshu Guo Mingshan Wang Yun Huang Hongmei Zhang Mengmeng Yin Jiangtao Liu Yuanhua Lin Xing Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期156-165,I0004,共11页
Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.... Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.Herein,a flame-retardant,low-cost and thermally stable long chain phosphate ester based(tributyl phosphate,TBP)electrolyte is reported,which can effectively enhance the cycling stability of highly loaded high-nickel LMBs with high safety through co-solvation strategy.The interfacial compatibility between TBP and electrode is effectively improved using a short-chain ether(glycol dimethyl ether,DME),and a specially competitive solvation structure is further constructed using lithium borate difluorooxalate(LiDFOB)to form the stable and inorganic-rich electrode interphases.Benefiting from the presence of the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)enriched with LiF and Li_(x)PO_(y)F_(z),the electrolyte demonstrates excellent cycling stability assembled using a 50μm lithium foil anode in combination with a high loading NMC811(15.4 mg cm^(-2))cathode,with 88%capacity retention after 120 cycles.Furthermore,the electrolyte exhibits excellent high-temperature characteristics when used in a 1-Ah pouch cell(N/P=0.26),and higher thermal runaway temperature(238℃)in the ARC(accelerating rate calorimeter)demonstrating high safety.This novel electrolyte adopts long-chain phosphate as the main solvent for the first time,and would provide a new idea for the development of extremely high safety and high-temperature electrolytes. 展开更多
关键词 Non-flammable electrolyte Long chain phosphate ester Solvation structure Lithium metal batteries Battery safety
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Transition of plasticity and fracture mode of Zr-Al-Ni-Cu bulk metallic glasses with network structures 被引量:1
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作者 蔡安辉 丁大伟 +4 位作者 安伟科 周果君 罗云 李江鸿 彭勇宜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2617-2623,共7页
Effect of network structure on plasticity and fracture mode of Zr?Al?Ni?Cu bulk metallic glasses (BMGs) was investigated. The microstructures of transversal and longitudinal sections were exposed by chemical etch... Effect of network structure on plasticity and fracture mode of Zr?Al?Ni?Cu bulk metallic glasses (BMGs) was investigated. The microstructures of transversal and longitudinal sections were exposed by chemical etching and observed by scanning electron microscopy (SEM). The mechanical properties were examined by room-temperature uniaxial compression test. The results show that both plasticity and fracture mode are significantly affected by the network structure and the alteration occurs when the size of the network structure reaches up to a critical value. When the cell size (dc) of the network structure is ~3μm, Zr-based BMGs characterize in plasticity that decreases with increasingdc. The fracture mode gradually transforms from single 45° shear fracture to double 45° shear fracture and then cleavage fracture with increasingdc. In addition, the mechanisms of the transition of the plasticity and the fracture mode for these Zr-based BMGs are also discussed. 展开更多
关键词 bulk metallic glass PLASTICITY fracture mode network structure
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From VIB‑to VB‑Group Transition Metal Disulfides:Structure Engineering Modulation for Superior Electromagnetic Wave Absorption 被引量:1
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作者 Junye Cheng Yongheng Jin +10 位作者 Jinghan Zhao Qi Jing Bailong Gu Jialiang Wei Shenghui Yi Mingming Li Wanli Nie Qinghua Qin Deqing Zhang Guangping Zheng Renchao Che 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期218-257,共40页
The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various field... The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance. 展开更多
关键词 Transition metal disulfides Electromagnetic wave absorption Impedance matching structure engineering modulation
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Regulating zinc ion transport behavior and solvated structure towards stable aqueous Zn metal batteries
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作者 Qiang Ma Aoen Ma +6 位作者 Shanguang Lv Bowen Qin Yali Xu Xianxiang Zeng Wei Ling Yuan Liu Xiongwei Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期609-626,I0015,共19页
Aqueous Zn metal batteries(AZMBs)with intrinsic safety,high energy density and low cost have been regarded as promising electrochemical energy storage devices.However,the parasitic reaction on metallic Zn anode and th... Aqueous Zn metal batteries(AZMBs)with intrinsic safety,high energy density and low cost have been regarded as promising electrochemical energy storage devices.However,the parasitic reaction on metallic Zn anode and the incompatibility between electrode and electrolytes lead to the deterioration of electrochemical performance of AZMBs during the cycling.The critical point to achieve the stable cycling of AZMBs is to properly regulate the zinc ion solvated structure and transfer behavior between metallic Zn anode and electrolyte.In recent years,numerous achievements have been made to resolve the formation of Zn dendrite and interface incompatible issues faced by AZMBs via optimizing the sheath structure and transport capability of zinc ions at electrode-electrolyte interface.In this review,the challenges for metallic Zn anode and electrode-electrolyte interface in AZMBs including dendrite formation and interface characteristics are presented.Following the influences of different strategies involving designing advanced electrode structu re,artificial solid electrolyte interphase(SEI)on Zn anode and electrolyte engineering to regulate zinc ion solvated sheath structure and transport behavior are summarized and discussed.Finally,the perspectives for the future development of design strategies for dendrite-free Zn metal anode and long lifespan AZMBs are also given. 展开更多
关键词 aqueous Zn metal batteries Zn metal anode Transport behavior Solvated structure Dendrite-free
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An effective strategy of constructing multi-metallic oxides of ZnO/ CoNiO_(2)/CoO/C microflowers for improved supercapacitive performance
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作者 Wei Guo Yan Zhang +1 位作者 Xiaxin Lei Shuang Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期1-8,共8页
In this work,a new ZnO/CoNiO_(2)/CoO/C metal oxides composite is prepared by cost-effective hydrothermal method coupled with annealing process under N_(2) atmosphere.Notably,the oxidation-defect annealing environment ... In this work,a new ZnO/CoNiO_(2)/CoO/C metal oxides composite is prepared by cost-effective hydrothermal method coupled with annealing process under N_(2) atmosphere.Notably,the oxidation-defect annealing environment is conducive to both morphology and component of the composite,which flower-like ZnO/CoNiO_(2)/CoO/C is obtained.Benefited from good chemical stability of ZnO,high energy capacity of CoNiO_(2) and CoO and good conductivity of C,the as-prepared sample shows promising electrochemical behavior,including the specific capacity of 1435 C·g^(-1) at 1 A·g^(-1),capacity retention of 87.3%at 20 A·g^(-1),and cycling stability of 90.5%for 3000 cycles at 5 A·g^(-1),respectively.Furthermore,the prepared ZnO/CoNiO_(2)/CoO/C/NF//AC aqueous hybrid supercapacitors device delivers the best specific energy of 55.9 W·h·kg^(-1) at 850 W·kg^(-1).The results reflect that the as-prepared ZnO/CoNiO_(2)/CoO/C microflowers are considered as high performance electrode materials for supercapacitor,and the strategy mentioned in this paper is benefit to prepare mixed metal oxides composite for energy conversion and storage. 展开更多
关键词 Composites ELECTROCHEMISTRY HYDROTHERMAL Transition metal oxides structural control SUPERCAPACITORS
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Synthesis and Coloring Mechanism of Metallic Glaze in R_(2)O-RO-Al_(2)O_(3)-SiO_(2)-P_(2)O_(5)System
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作者 CHEN Yanlin FU Qiong +3 位作者 YANG Yuhang WEI Feng LIU Dongyang WANG Juan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1416-1424,共9页
A copper-red and silver-white metallic glaze of R_(2)O-RO-Al_(2)O_(3)-SiO_(2)-P_(2)O_(5)system was synthesized by adjusting the firing temperature and glaze components.The coloration mechanism of the metallic glaze wa... A copper-red and silver-white metallic glaze of R_(2)O-RO-Al_(2)O_(3)-SiO_(2)-P_(2)O_(5)system was synthesized by adjusting the firing temperature and glaze components.The coloration mechanism of the metallic glaze was revealed via investigation of the microstructure of the glaze.Our research reveals that the metallic glaze with different colors is mainly due to the amount of Fe_(2)O_(3).The metallic glaze shows a silver-white luster due to a structural color ofα-Fe_(2)O_(3)crystals with a good orientation when the sample contains 0.0939 mol of Fe_(2)O_(3),maintaining temperatures at 1150℃for 0.5 h.The metallic glaze is copper-red which is dominated by the coupling of chemical and structural color ofα-Fe_(2)O_(3)crystals when the sample contains 0.0783 mol of Fe_(2)O_(3).After testing the amount of SiO_(2),we find that 4.0499 mol is the optimal amount to form the ceramic network,and 0.27 mol AlPO_(4)is the best amount to promote phase separation. 展开更多
关键词 metallic glaze phase separation coloring mechanism chemical color structural color
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Tuning the surface electronic structure of noble metal aerogels to promote the electrocatalytic oxygen reduction
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作者 Hongxing Yuan Wei Gao +2 位作者 Xinhao Wan Jianqi Ye Dan Wen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期557-564,I0013,共9页
The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion devices.Regulating the electronic structure of electrocatalysts by ligands has received partic... The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion devices.Regulating the electronic structure of electrocatalysts by ligands has received particular attention in deriving valid ORR electrocatalysts.Here,the surface electronic structure of Ptbased noble metal aerogels(NMAs)was modulated by various organic ligands,among which the electron-withdrawing ligand of 4-methylphenylene effectively boosted the ORR electrocatalysis.Theoretical calculations suggested the smaller energy barrier for the transformation of O^(*) to OH^(*) and downshift the d-band center of Pt due to the interaction between 4-methylphenylene and the surface metals,thus enhancing the ORR intrinsic activity.Both Pt3Ni and Pt Pd aerogels with 4-methylphenylene decoration performed significant enhancement in ORR activity and durability in different media.Remarkably,the 4-methylphenylene modified Pt Pd aerogel exhibited the higher halfwave potential of 0.952 V and the mass activity of 10.2 times of commercial Pt/C.This work explained the effect of electronic structure on ORR electrocatalytic properties and would promote functionalized NMAs as efficient ORR electrocatalysts. 展开更多
关键词 Noble metal aerogels Surface electronic structure ORR ELECTROCATALYST Organic ligands
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Universal basis underlying temperature, pressure and size induced dynamical evolution in metallic glass-forming liquids
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作者 张华平 范蓓蓓 +1 位作者 吴佳琦 李茂枝 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期134-142,共9页
The dramatic temperature-dependence of liquids dynamics has attracted considerable scientific interests and efforts in the past decades, but the physics of which remains elusive. In addition to temperature, some other... The dramatic temperature-dependence of liquids dynamics has attracted considerable scientific interests and efforts in the past decades, but the physics of which remains elusive. In addition to temperature, some other parameters, such as pressure, loading and size, can also tune the liquid dynamics and induce glass transition, which makes the situation more complicated. Here, we performed molecular dynamics simulations for Ni_(50)Zr_(50) bulk liquid and nanodroplet to study the dynamics evolution in the complex multivariate phase space, especially along the isotherm with the change of pressure or droplet size. It is found that the short-time Debye–Waller factor universally determines the long-time relaxation dynamics no matter how the temperature, pressure or size changes. The basic correlation even holds at the local atomic scale. This finding provides general understanding of the microscopic mechanism of dynamic arrest and dynamic heterogeneity. 展开更多
关键词 metallic glass-forming liquids structure relaxation dynamical heterogeneity Debye–Waller factor
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Tailoring local structures of atomically dispersed copper sites for highly selective CO_(2) electroreduction
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作者 Kyung‐Jong Noh Byoung Joon Park +5 位作者 Ying Wang Yejung Choi Sang‐Hoon You Yong‐Tae Kim Kug‐Seung Lee Jeong Woo Han 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期79-90,共12页
Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construc... Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construction of optimal local electronic structures for nitrogen‐coordinated Cu sites(Cu–N_(4))on carbon remains challenging.Here,we synthesized the Cu–N–C catalysts with atomically‐dispersed edge‐hosted Cu–N_(4) sites(Cu–N_(4)C_(8))located in a micropore between two graphitic sheets via a facile method to control the concentration of metal precursor.Edge‐hosted Cu–N_(4)C_(8) catalysts outperformed the previously reported M–N–C catalysts for CO_(2)‐to‐CO conversion,achieving a maximum CO Faradaic efficiency(FECO)of 96%,a CO current density of–8.97 mA cm^(–2) at–0.8 V versus reversible hydrogen electrode(RHE),and over FECO of 90%from–0.6 to–1.0 V versus RHE.Computational studies revealed that the micropore of the graphitic layer in edge‐hosted Cu–N_(4)C_(8) sites causes the d‐orbital energy level of the Cu atom to shift upward,which in return decreases the occupancy of antibonding states in the*COOH binding.This research suggests new insights into tailoring the locally coordinated structure of the electrocatalyst at the atomic scale to achieve highly selective electrocatalytic reactions. 展开更多
关键词 atomic local structure density functional theory electrochemical CO_(2)reduction metal nitrogen‐doped carbon single‐atom catalyst
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Immobilization of Oxyanions on the Reconstructed Heterostructure Evolved from a Bimetallic Oxysulfide for the Promotion of Oxygen Evolution Reaction 被引量:1
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作者 Kai Yu Hongyuan Yang +6 位作者 Hao Zhang Hui Huang Zhaowu Wang Zhenhui Kang Yang Liu Prashanth W.Menezes Ziliang Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期547-564,共18页
Efficient and durable oxygen evolution reaction(OER)requires the electrocatalyst to bear abundant active sites,optimized electronic structure as well as robust component and mechanical stability.Herein,a bimetallic la... Efficient and durable oxygen evolution reaction(OER)requires the electrocatalyst to bear abundant active sites,optimized electronic structure as well as robust component and mechanical stability.Herein,a bimetallic lanthanum-nickel oxysulfide with rich oxygen vacancies based on the La_(2)O_(2)S prototype is fabricated as a binder-free precatalyst for alkaline OER.The combination of advanced in situ and ex situ characterizations with theoretical calculation uncovers the synergistic effect among La,Ni,O,and S species during OER,which assures the adsorption and stabilization of the oxyanion SO_(4)^(2-)onto the surface of the deeply reconstructed porous heterostructure composed of confining Ni OOH nanodomains by La(OH)_3 barrier.Such coupling,confinement,porosity and immobilization enable notable improvement in active site accessibility,phase stability,mass diffusion capability and the intrinsic Gibbs free energy of oxygen-containing intermediates.The optimized electrocatalyst delivers exceptional alkaline OER activity and durability,outperforming most of the Ni-based benchmark OER electrocatalysts. 展开更多
关键词 Lanthanum-nickel oxysulfide Rare earth metal Immobilization of oxyanions structural reconstruction Oxygen evolution catalysis
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Structural origin for composition-dependent nearest atomic distance in Cu–Zr metallic glass
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作者 张驰 刘华山 彭海龙 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期545-549,共5页
We systematically investigate the structures of Cu–Zr metallic glass(MG) by varying the Cu concentration in classic molecular-dynamics simulation. From the pair distribution functions(PDFs), it is found that the near... We systematically investigate the structures of Cu–Zr metallic glass(MG) by varying the Cu concentration in classic molecular-dynamics simulation. From the pair distribution functions(PDFs), it is found that the nearest atomic distance between Zr atom and Zr atom increases significantly after adding Cu, which is related to the composition-dependent coordination behavior between Cu atom and Zr atom in the nearest neighbors. The portion of PDF related to the nearest connection is decomposed into the contributions from quadrilateral structure, pentagonal structure, hexagonal structure,and heptagonal bipyramid structure. Although the population of denser structures, i.e. 5-, 6-, and 7-number sharing ones,increases with Cu addition increasing, the connection distances between the central atoms in all these bipyramids increase for Zr–Zr pairs, leading to the expansion of Zr–Zr nearest atomic distance. These results unveil the effect of the interplay between chemical interaction and geometric packing on the atomic-level structure in Cu–Zr metallic glasses. 展开更多
关键词 metallic glass structure molecular dynamics
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Probing electronic structures of transition metal complexes using electron paramagnetic resonance spectroscopy
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作者 Shengfa Ye 《Magnetic Resonance Letters》 2023年第1期43-60,I0003,共19页
Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,h... Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,how to extract the underlying electronicstructure information inevitably poses a major challenge to beginners,in particular for systems with S>1/2.In fact,the physical principles of transition metal EPR have long been well-established and since 1970s a series of dedicated voluminous monographs have been published already.Not surprisingly,they are not appropriate stating points for novices to grasp a panorama of the profound theory prior to scrutinizing in-depth references.The present review aims to fill this gap to provide a perspective of transition metal EPR and unveil some peculiar subtleties thereof on the basis of our recent work. 展开更多
关键词 EPR Electronic structures Transition metal complexes Spin Hamiltonian
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Effects of material of metallic frame on the penetration resistances of ceramic-metal hybrid structures 被引量:7
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作者 Xuanyi An Chao Tian +1 位作者 Qitian Sun Yongxiang Dong 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第1期77-87,共11页
The effects of metallic material on the penetration resistances of ceramic-metal hybrid structures against vertical long-rod tungsten projectiles were studied by artillery-launched experiments and numerical simulation... The effects of metallic material on the penetration resistances of ceramic-metal hybrid structures against vertical long-rod tungsten projectiles were studied by artillery-launched experiments and numerical simulation.Hybrid structures with rectangular cores in transverse orthogonal arrangement and slidefitting ceramic inserts of zirconia toughened alumina prisms were fabricated with titanium alloy TC4(Ti6 Al4 V),AISI 4340 steel and 7075 aluminum alloy panels,respectively.The results showed that the hybrid structure of Ti6A14V exhibited the highest penetration resistance,followed by that of 7075 aluminum alloy with the same area density.The penetration resistance of the hybrid structure of AISI4340 steel was the lowest.The underlying mechanisms showed that the metallic material of a ceramicmetal hybrid structure can directly affect its energy absorption from the impact projectile,which further affects its penetration resistance.Different metallic frames exhibited different failure characteristics,resulting in different constraint conditions or support conditions for ceramic prisms.The high penetration resistance of the Ti6Al4V hybrid structure was due to its stronger back support to ceramic prisms as compared with that of AISI 4340 steel hybrid structure,and better constraint condition for ceramic prisms by metallic webs as compared with that of 7075 aluminum alloy hybrid structure.The results of mass efficiency and thickness efficiency showed that the Ti6Al4V hybrid structure has advantages in reducing both the thickness and the mass of protective structure.In addition,because the ceramic-metal hybrid structures in the present work were heterogeneous,impact position has slight influence on their penetration resistances. 展开更多
关键词 Hybrid structures ZIRCONIA toughened alumina PENETRATION resistance Long-rod PROJECTILE metallic FRAME
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Electronic structures and elastic properties of monolayer and bilayer transition metal dichalcogenides MX_2(M= Mo,W;X= O,S,Se,Te):A comparative first-principles study 被引量:5
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作者 曾范 张卫兵 唐壁玉 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期436-443,共8页
First-principle calculations with different exchange-correlation functionals, including LDA, PBE, and vd W-DF functional in the form of opt B88-vd W, have been performed to investigate the electronic and elastic prope... First-principle calculations with different exchange-correlation functionals, including LDA, PBE, and vd W-DF functional in the form of opt B88-vd W, have been performed to investigate the electronic and elastic properties of twodimensional transition metal dichalcogenides(TMDCs) with the formula of MX2(M = Mo, W; X = O, S, Se, Te) in both monolayer and bilayer structures. The calculated band structures show a direct band gap for monolayer TMDCs at the K point except for MoO2 and WO2. When the monolayers are stacked into a bilayer, the reduced indirect band gaps are found except for bilayer WTe2, in which the direct gap is still present at the K point. The calculated in-plane Young moduli are comparable to that of graphene, which promises possible application of TMDCs in future flexible and stretchable electronic devices. We also evaluated the performance of different functionals including LDA, PBE, and opt B88-vd W in describing elastic moduli of TMDCs and found that LDA seems to be the most qualified method. Moreover, our calculations suggest that the Young moduli for bilayers are insensitive to stacking orders and the mechanical coupling between monolayers seems to be negligible. 展开更多
关键词 transition metal dichalcogenides bilayer structures elastic properties electronic structure
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Design for a Crane Metallic Structure Based on Imperialist Competitive Algorithm and Inverse Reliability Strategy 被引量:6
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作者 Xiao-Ning Fan Bo Zhi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期900-912,共13页
Uncertainties in parameters such as materials, loading, and geometry are inevitable in designing metallic structures for cranes. When considering these uncertainty factors, reliability-based design optimization (RBDO... Uncertainties in parameters such as materials, loading, and geometry are inevitable in designing metallic structures for cranes. When considering these uncertainty factors, reliability-based design optimization (RBDO) offers a more reasonable design approach. However, existing RBDO methods for crane metallic structures are prone to low convergence speed and high computational cost. A unilevel RBDO method, combining a discrete imperialist competitive algorithm with an inverse reliabil- ity strategy based on the performance measure approach, is developed. Application of the imperialist competitive algorithm at the optimization level significantly improves the convergence speed of this RBDO method. At the reli- ability analysis level, the inverse reliability strategy is used to determine the feasibility of each probabilistic constraint at each design point by calculating its a-percentile per- formance, thereby avoiding convergence failure, calcula- tion error, and disproportionate computational effort encountered using conventional moment and simulation methods. Application of the RBDO method to an actual crane structure shows that the developed RBDO realizes a design with the best tradeoff between economy and safety together with about one-third of the convergence speed and the computational cost of the existing method. This paper provides a scientific and effective design approach for the design of metallic structures of cranes. 展开更多
关键词 Crane metallic structure Reliability-baseddesign optimization Imperialist competitive algorithmPerformance measure approach Inverse reliabilitystrategy
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Micro-nanostructural designs of bifunctional electrocatalysts for metal-air batteries 被引量:8
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作者 Fang Shi Xuefeng Zhu Weishen Yang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第3期390-403,共14页
Water-based rechargeable metal-air batteries play an important role in the storage and conversion of renewable electric energy.However,the sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution re... Water-based rechargeable metal-air batteries play an important role in the storage and conversion of renewable electric energy.However,the sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)have limited the practical application of rechargeable metal-air batteries.Most of reviews were focused on single functional electrocatalysts while few on bifunctional electrocatalysts.It is indispensable but challenging to design a bifunctional electrocatalyst that is active and stable to the two reactions.Recently,attempts to develop high active bifunctional electrocatalysts for both ORR and OER increase rapidly.Much work is focused on the micro-nano design of advanced structures to improve the performance of bifunctional electrocatalyst.Transition-metal materials,carbon materials and composite materials,and the methods developed to prepare micro-nano structures,such as electrochemical methods,chemical vapor deposition,hydrothermal methods and template methods are reported in literatures.Additionally,many strategies,such as adjustments of electronic structures,oxygen defects,metal-oxygen bonds,interfacial strain,nano composites,heteroatom doping etc.,have been used extensively to design bifunctional electrocatalysts.To well understand the achievements in the recent literatures,this review focuses on the micro-nano structural design of materials,and the related methods and strategies are classed into two groups for the improvement of intrinsic and apparent activities.The fine adjustment of nano structures and an in-depth understanding of the reaction mechanism are also discussed briefly. 展开更多
关键词 Oxygen reduction reaction Oxygen evolution reaction Rechargeable metal-air batteries Bifunctional electrocatalysts micro-nano structure
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Metal-organic Coordination Architectures of Triazole-ligands: Syntheses, Structures and Luminescent Properties 被引量:3
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作者 王多志 孙学森 +1 位作者 张建斌 刘晨江 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第8期1236-1244,共9页
Five new transitional metal complexes with 4,4′-bis(1,2,4-triazol-1-ylmethyl)- biphenyl (L1), 1,4-bis(1,2,4-triazol-1-ylmethyl)naphthalene (L2) and 1-(1H-1,2,4-triazol-l-yl)- 3-phenyl-2-one (L3) were synt... Five new transitional metal complexes with 4,4′-bis(1,2,4-triazol-1-ylmethyl)- biphenyl (L1), 1,4-bis(1,2,4-triazol-1-ylmethyl)naphthalene (L2) and 1-(1H-1,2,4-triazol-l-yl)- 3-phenyl-2-one (L3) were synthesized and characterized by elemental analysis, IR and X-ray diffraction. Complexes 1-3 have one-dimensional (1-D) chain structures, and L1 adopts a gauche-gauche conformation with the shortest N...N distance between the two N donors in complexes 1-3; however, L2 adopts a trans-gauche conformation in complex 4. Complex 5 is a mononuclear structure, and L3 adopts a monodentate coordination mode. The fluorescence properties of ligands L1 and complexe 1 have been investigated. 展开更多
关键词 TRIAZOLE metal complexes synthesis crystal structure
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