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Quasilinear dispersion in electronic band structure and high Seebeck coefficient in CuFeS2-based thermoelectric materials

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Physical Review materials 2020年第2期4卷 025405-025405页

作者： Hongyao Xie Xianli Su Shiqiang Hao Christopher Wolverton Ctirad Uher Xinfeng Tang Mercouri G. Kanatzidis State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China Department of Chemistry Northwestern University Evanston Illinois 60208 USA Department of Materials Science and Engineering Northwestern University Evanston Illinois 60208 USA Department of Physics University of Michigan Ann Arbor Michigan 48109 USA

The earth-abundant natural mineral chalcopyrite CuFeS2 is a potential n-type thermoelectric material because of its large Seebeck coefficient at high carrier concentrations. For a long time, the large Seebeck coefficient of CuFeS2 has been attributed to a large electron effective mass, but the reasons for this and the unusual carrier concentration dependent behavior have rarely been discussed. Here, we systematically investigated the special transport behavior of CuFeS2 and found the classical parabolic band model to be inadequate in explaining it. Our experimental and theoretical studies indicate that there are two flat electronic pockets at the Γ and Z points of the Brillouin zone near the conduction band edge of CuFeS2 that dominate the charge transport. These electronic pockets result from nonparabolic quasilinearly dispersing bands that give rise to a linear wave vector dependent energy (E∼k) and a carrier density dependent effective mass (m*∼m0n1/3). Such a strong carrier concentration dependent carrier effective mass results in the high Seebeck coefficient of CuFeS2 compound under a large carrier density. The work demonstrates that quasilinearly dispersing bands can give strongly enhanced Seebeck coefficient, and could be useful in optimizing the properties of thermoelectric materials.

关键词： Thermoelectric effects

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Taming the Ion-Dipole Interaction via Rational Diluent Selection for Low-Temperature Li-Metal Batteries

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Angewandte Chemie 2025年

作者： Zhenglu Zhu Yan Li Jie Ji Xiaoqun Qi Junqing Pan Jiwei Ma Long Qie Yunhui Huang State Key Laboratory of Chemical Resource Engineering College of Chemistry Beijing University of Chemical Technology Beijing 100029 State Key Laboratory of Material Processing and Die & Mold Technology School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan Hubei 430074 Institute of New Energy for Vehicles School of Materials Science and Engineering Tongji University Shanghai 201804

Developing advanced electrolytes with high Li affinity is crucial for achieving long-cycling lithium metal batteries (LMBs). However, the strong Li + -solvent interactions in conventional electrolytes often induce difficult Li + desolvation especially under low-temperature conditions, resulting in the formation of fragile electrode interfaces involving solvents, and thus dissatisfactory cycling stability of LMBs. Herein, by introducing various diluents into the lithium hexafluorophosphate in 1, 2-dimethoxyethane electrolyte, we reveal that Li + desolvation is influenced by not only the diluent-solvent interaction but also the diluent-anion interaction. Based on these findings, a diluent selection parameter (DSP), which is calculated based on the product of interaction energies of diluent-solvent/diluent-Li + and diluent-anion/diluent-Li + , is proposed for diluent selection. A diluent with a larger DSP is more favorable for promoting Li + desolvation and improving the low-temperature performance of LMBs. With the rationally selected 1, 2-dichloroethane diluent (DSP=3.95), the Li Cu cell enables high Li reversibility (98.5 % after 300 cycles). Li LiFePO 4 cell barely loses capacity at −20 °C for 300 cycles. The Li LiNi 0.8 Co 0.1 Mn 0.1 O 2 cell with the anode-to-cathode capacity ratio of 2.7 retains 87 % capacity retention after 100 cycles. This work provides new insights into taming strong Li-solvent interactions and offers a new paradigm for advanced electrolyte design.

关键词： Electrolyte design Li+ desolvation Li reversibility Interaction energy Selection parameter

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Unveiling the Effect of Solvent Polarity on the Excited state Intramolecular Proton Transfer and Hydrogen Bond Mechanisms of Dhp

SSRN

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SSRN 2022年

作者： Song, Yao-Dong Wang, Qian-Ting Chen, Li School of Electronic Electrical Engineering and Physics Fujian University of Technology Fujian Fuzhou350118 China Fujian Provincial Key Laboratory of Advanced Materials Processing and Application China Sanming University Fujian Sanming365004 China Fujian Provincial Engineering Research Center of Die & Mold China Mould Technology Development Base of Fujian Province China Fuzhou Innovation Platform for Novel Materials and Mould Technology China Fujian University of Technology Fujian Fuzhou350118 China

In this present work, using density functional theory and time-dependent density functional theory, the mechanism of excited state intramolecular proton transfer of DHP in ether, 1-butanol, 1-propanol and acetonitrile phases was systematically studied. The optimized geometry includes normal structure and tautomeric structure. The fluorescence spectrum and visible absorption spectrum calculated based on geometric structure agree with the experimental data. The data of bond lengths and bond angles related to hydrogen bonds indicate that hydrogen bonds are strengthened in the S 1 state. Frontier molecular orbital analysis combined with Hirshfeld's method shows that electron densities are distributed in different solvents. Infrared vibration spectra show that the hydrogen bond strength decreases with the increase of solvent polarity. Finally, through the analysis of the potential energy surface, it is found that the excited state intramolecular proton transfer becomes more and more difficult as the polarity of the solvent increases. © 2022, The Authors. All rights reserved.

关键词： Hydrogen bonds

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Cotton-derived oxygen/sulfur co-doped hard carbon as advanced anode material for potassium-ion batteries

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Chinese Chemical Letters 2020年第1期31卷 217-222页

作者： Baolin Xu Shihan Qi Fang Li Xiaoxin Peng Jinfeng Cai Jiaojiao Liang Jianmin Ma School of Physics and Electronics Hunan UniversityChangsha 410082China Yiyang Wanjingyuan Electronics Co. Ltd.Yiyang 413000China College of Traffic Engineering Hunan University of TechnologyZhuzhou 412008China Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002China State Key Lab of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072 China

Hard carbon is regarded as promising anode materials for potassium-ion batteries(KIBs)owing to their low price and easy ***,the limited rate capability still needs to be ***,we demonstrate the fabrication of oxygen/sulfur co-doped hard carbon through a facile hydrolyzationsulfuration process of skimmed *** simultaneous dopants significantly improve potassium ion diffusion *** served as the anode for KIBs,this hydrolyzed hard carbon delivered a high reversible capacity(409 mAh/g at 0.1 A/g),superior rate capability(135 mAh/g at 2 A/g)and excellent cyclability(about 120 mAh/g overt 500 cycles at 2 A/g).This work provides a facile strategy to prepare low-cost doped-hard carbon with superior potassium storage property.

关键词： Carbon Doping Anode Potassium-ion battery Biomass

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Ultrafast optical response and ablation mechanisms of molybdenum disulfide under intense femtosecond laser irradiation

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Light(Science & Applications) 2020年第1期9卷 1265-1272页

作者： Changji Pan Lan Jiang Jingya Sun Qingsong Wang Feifei Wang Kai Wang Yongfeng Lu Yeliang Wang Liangti Qu Tianhong Cui Laser Micro/Nano-Fabrication Laboratory School of Mechanical EngineeringBeijing Institute of Technology100081 BeijingP.R.China Department of Electrical Engineering University of Nebraska-LincolnLincolnNE 68588-0511USA School of Information and Electronics Beijing Institute of Technology100081 BeijingP.R.China Key Laboratory for Advanced Materials Processing Technology Ministry of Education of ChinaDepartment of Mechanical EngineeringTsinghua University100084 BeijingP.R.China Department of Mechanical Engineering University of MinnesotaMinneapolisMN 55455USA

Numerous valuable studies on electron dynamics have focussed on the extraordinary properties of molybdenum disulfide(MoS_(2));however,most of them were confined to the level below the damage *** the electron dynamics of MoS_(2) under intense ultrafast laser irradiation was investigated by experiments and *** kinds of ablation mechanisms were revealed,which led to two distinct types of electron dynamics and final ablation *** a higher fluence,the emergence of superheated liquid induced a dramatic change in the transient reflectivity and micro-honeycomb *** a lower fluence,the material was just removed by sublimation,and the ablation structure was relatively flat.X-ray photoelectron spectroscopic(XPS)measurements demonstrated that thermal decomposition only occurred at the higher ***,a theoretical model was developed to deeply reveal the ultrafast dynamics of MoS_(2) *** simulation results were in good agreement with the temporal and spatial reflectivity distribution obtained from the *** electron and lattice temperature evolution was also obtained to prove the ablation *** results revealed ultrafast dynamics of MoS_(2) above the damage threshold and are helpful for understanding the interaction mechanism between MoS_(2) and intense ultrafast lasers,as well as for MoS_(2) processing applications.

关键词： intense molybdenum disulfide

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Boosting the Alkali Metal Ions Storage Performance of Layered Nb2C with a Molecular Welding Strategy

SSRN

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SSRN 2022年

作者： Liu, Maocheng Zhang, Dongting Liu, Bao Tian, Chenyang Zhao, Bei Wang, Yaqin Wang, Yuanyi Hu, Yuxia Kong, Lingbin Luo, Dan Chen, Zhongwei State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of Technology Lanzhou730050 China School of Materials Science and Engineering Lanzhou University of Technology Lanzhou730050 China School of Materials Science and Engineering Xiangtan University Hunan Xiangtan411105 China Department of Chemical Engineering Waterloo Institute for Nanotechnology University of Waterloo WaterlooONN2L 3G1 Canada Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices School of Information and Optoelectronic Science and Engineering South China Normal University Guangzhou510006 China

MXenes are promising 2D-layered anode materials for rechargeable batteries. However, MXenes suffer from severe volume expansion and sluggish ion diffusion kinetics during ions insertion/extraction, leading to inferior battery performance. Herein, we developed a molecular welding strategy to stabilize layered structure and enlarge interlayer spacing of Nb2C through a dehydration condensation reaction between the -COOH groups in 1,3,5-benzenetricarboxylic acid (BTC) molecules and -NH2 groups on the surface of the aminofunctionalized Nb2C, which enable the BTC to chemically weld into interlayers of Nb2C (named as Nb2C/BTC). The intercalation of BTC into Nb2C contributes both pillar and strain effects to the 2D-layered Nb2C, rendering its maximum utilization. Such Nb2C/BTC with enlarged interlayer spacing and inhibited volume variation could remarkably promote the rate capability and cycling stability of Nb2C when used as the electrodes of alkali metal ions batteries. A decent Li+/Na+ ions storage capacity-retention of 86.6% (0.1 A g-1)/93.5% (1.0 A g-1) can be presented. A much reduced ion diffusion barrier of 0.88 eV is also delivered in Nb2C/BTC through DFT theoretical calculations. This work provides a new strategy for broadening the interlayer spacing and inhibiting the severe volume variation of MXenes for enhanced alkali metal ions storage. © 2022, The Authors. All rights reserved.

关键词： Anodes

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Preparation of Al-Zn-Mg-Cu alloy semisolid slurry through a water-cooled serpentine pouring channel

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China Foundry 2019年第1期16卷 31-39页

作者： Wen-zhi Zhu Wei-min Mao Qing-song Wei Chen Hui Yu-sheng Shi State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The semisolid slurry of Al-Zn-Mg-Cu alloy was prepared through a self-designed water-cooled copper serpentine pouring channel(WSPC) machine. Influences of pouring temperature, the number of turns and the cooling water flow rate on the microstructure of the semisolid Al-Zn-Mg-Cu alloy slurry were investigated. The results show that the semisolid Al-Zn-Mg-Cu alloy slurry with satisfactory quality can be generated by the WSPC when the pouring temperature is in the range between 680 ℃ and 700 ℃. At a given pouring temperature, the average grain size of primary α-Al decreases and the shape factor increases with the increase of the number of turns. When the cooling water flow rate is 450 L·h^(-1), the obtained semisolid slurry is optimal. During the preparation of the semisolid Al-Zn-Mg-Cu alloy slurry with low superheat pouring, the alloy melt has mixed inhibition and convection flow characteristics by "self-stirring". When the alloy melt flows through the serpentine channel, the chilling effect of the inner wall of the channel, the convection and mixed inhibition of the alloy melt greatly promote the heterogeneous nucleation and grain segregation. This effect destroys the dendrite growth mode under traditional solidification conditions, and the primary nuclei gradually evolve into spherical or nearspherical grains.

关键词： Al-Zn-Mg-Cu Alloy semisolid slurry water-cooled serpentine channel primary α-Al

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Controlled deintercalation of graphene/organic superlattices with dense atomic-scale steric Schottky heterojunctions for extreme microwave absorption

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Nature communications 2025年第1期16卷 5804页

作者： Ruopeng Cui Yi Li Xuefei Zhang Zewen Duan Biao Zhao Chunlei Wan State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing China. College of Mathematics and Physics Beijing University of Chemical Technology Beijing China. School of Microelectronics Fudan University Shanghai China. zhao_biao@***. State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing China. wancl@***.

Integrating 2D (semi)metals and semiconductors into atomic-scale Schottky heterojunctions offers a promising pathway for achieving robust charge separation, crucial for microwave absorbers, electromagnetic interference shielding materials, electrocatalysts, photocatalysts, etc. However, conventional bottom-up assembly approaches often encounter challenges of severe agglomeration of 2D components and non-basal contacts due to lattice mismatch, resulting in a suboptimal interfacial density and insufficient charge separation. This study introduces a top-down approach involving the thermal deintercalation of graphene/alkylamine superlattices, leading to the in-situ formation of Schottky heterojunctions between the thermally reduced p-type rGO-alkylamine superlattice phase and entirely deintercalated semimetallic rGO phase (rGO denotes reduced graphene oxide), which can be flexibly tuned by the length of the alkylamines. A spatial network of 2D/2D vertical/lateral Schottky heterojunctions is thus formed with high interfacial density, greatly facilitating charge separation, and thereby strengthening polarization loss while reducing conduction loss. This ensures steady permittivity in the Ku band, maintaining strong absorption under small oblique incidence. Accordingly, a record-high simulated far-field bistatic radar cross-section reduction of 72.68 dB at 1° is attained along with diversified adaptive multifunctionality. This paper provides a groundbreaking avenue realizing spatially distributed atomic-scale 2D/2D Schottky heterojunctions in 2D materials, promoting various related functional materials.

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Controlled preparation of ordered dendritic nanoclusters at Au fractal biointerfaces

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Chemical Physics Letters 2023年第1期829卷

作者： Tong-Kai Zhang Zi-Qian Yi Kai-Qi Ye Wei Geng Yao-Qi Huang Ge Tian Xiao-Yu Yang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & School of Materials Science and Engineering & Shenzhen Research Institute & Laoshan Laboratory Wuhan University of Technology Wuhan 430070 China School of Chemical Engineering and Technology Sun Yat-Sen University 2 Daxue Road Zhuhai 519082 China School of Engineering and Applied Sciences Harvard University MA 02138 USA

Owing to their ubiquitous use by natural systems, Au fractal structures by electrodeposition have been included in the design of new functional materials , yet a need exists for studying probe factors that influence the nature of materials produced in this process. In this investigation, we observe the presence of HCl results in a uniform structure of individual Au clusters. Also, the increase of deposition potential causes a decreasing size of Au cluster by accelerating the deposition process . Finally, as the deposition time becomes longer, significant increases occur in areas, densities, and fractal dimensions of individual Au clusters on the biointerface.

关键词： Hierarchical fractal biointerface Electrochemical deposition Au dendritic clusters HCl Deposition potential and time

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Direct C(sp³)-H functionalization with thiosulfonates via photoredox catalysis

Green Synthesis and Catalysis

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Green synthesis and Catalysis 2024年

作者： Liu, Linfeng Pang, Yujian Ma, Canliang Zhou, Daiqing Zhang, Wenjie Huang, Jin Sun, Jie Qiu, Jiangkai Liu, Yihuan Shen, Lei Li, Zhenjiang Guo, Kai State Key Laboratory Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University 30 Puzhu Road South Nanjing 211816 China College of Food Science and Light Industry Nanjing Tech University 30 Puzhu Road South Nanjing 211816 China Institute of Nanjing Advanced Biomaterials & Processing Equipment No. 1 Xiushan Middle Road Lishui Economic Development Zone Nanjing 211299 China

While C(sp3)-S bonds exist in many biologically active compounds, the direct catalytic C(sp3)-H thiolation remains elusive. Herein, we report a convenient and green C(sp3)-H thiolation approach mediated by using tetra... 详细信息

While C(sp³)-S bonds exist in many biologically active compounds, the direct catalytic C(sp³)-H thiolation remains elusive. Herein, we report a convenient and green C(sp³)-H thiolation approach mediated by using tetrabutylammonium decatungstate (TBADT) as a hydrogen atom transfer (HAT) photocatalyst. A wide range of C(sp³)-H bond-containing etheric, allylic, alkyl, ketonic, amidic substrates and sulfonyl-based SOMOphiles participated in the reaction, producing thioethers with high efficiency. The present protocol features green characteristics, such as being free of harmful oxidants and additives;step-economic;redox-neutral;and amenable to scale-up assisted by continuous-flow technology. © 2024 Fudan University

关键词： C(sp3)-H bond Continuous-flow technology Organosulfur molecules Photoredox catalysis

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