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Stacking control in graphene-based materials: A promising method for fascinating physical properties

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Frontiers of physics 2019年第2期14卷 45-46页

作者： Ji-Liang Zhang guang-cun shan Department of Energy and Materials Engineering Dongguk UniversitySeoul 04620Republic of Korea Department of Materials Science and Engineering City University of Hong KongKowloonHong Kong SARChina Institute of Quantum Sensing School of Instrumentation Science and Opto-Electronic EngineeringBeihang UniversityBeijing 100191China

Graphene, defined as a single atomic plane of graphite, is a semimetal with a small overlap between the valence and conduction bands. The stacking of graphene up to several atomic layers can lead to diverse physical properties, depending on the stacking method. Bi layer graphene is also a semimetal, adopting the AB-stacked (or Bernal-stacked) structure or the rare AA-stacked structure . Trilayer or few-layer graphene (FLG) can be semimetals or semiconductors, depending on whether they adopt Bernal (ABA) stacking or rhoinbohedral (ABC) stacking.

关键词： graphene-based materials few-layer graphene (FLG) adopt Bernal (ABA)

Theoretical study of photon emission from single quantum dot emitter coupled to surface plasmons

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Frontiers of physics 2011年第3期6卷 313-319页

作者： guang-cun shan Shu-ying BAO Kang ZHANG Wei HUANG Institute of Advanced Materials （IAM） Nanjing University of Posts and Telecommunications Nanjing 210003 China Department of Physics and Materials Science City University of Hong Kong Kowloon Hong Kong China Department of Physics Fudan University Shanghai 200433 China School of Information and Electronics Beijing Institute of Technology Beijing 500081 China

Motivated by the recent pioneering advances on nanoscale plasmonics and also nanophotonics tech- nology based on the surface plasmons （SPs）, in this work, we give a master equation model in the Lindblad form and investigate the quantum optical properties of single quantum dot （QD） emitter coupled to the SPs of a metallic nanowire. Our main results demonstrate the QD luminescence results of photon emission show three distinctive regimes depending on the distance between QD and metallic nanowire, which elucidates a crossover passing from being metallic dissipative for much smaller emitter-nanowire distances to surface plasmon （SP） emission for larger separations at the vicinity of plasmonic metallic nanowire. Besides, our results also indicate that, for both the resonant case and the detuning case, through measuring QD emitter luminescence spectra and second-order correlation functions, the information about the QD emitter coupling to the SPs of the dissipative metallic nanowire can be extracted. This theoretical study will serve as an introduction to un- derstanding the nanoplasmonic imaging spectroscopy and pave a new way to realize the quantum information devices.

关键词： quantum plasmonics quantum optics metallic nanowire surface plasmon （SP） quan-tum dot

Steady-state property and dynamics in graphene-nanoribbon- array lasers

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Frontiers in Biology 2012年第5期7卷 527-532页

作者： Xing-Hai Zhao guang-cun shan Chan-Hung Shek Institute of Electronic Engineering China Academy of Engineering PhysicsMianyang 621900China Department of Physics and Materials Science City University of Hong KongHong Kong SARChina

In this work, we present a schematic configuration and device model for a graphene-nanoribbon （GNR）-array-based nanolaser, which consists of a three-variable rate equations that takes into account carrier capture and Pauli blocking in semiconductor GNR-array lasers to analyze the steady- state properties and dynamics in terms of the role of the capture rate and the gain coefficient in GNR array nanolasers. Furthermore, our GNR-array nanolaser device model can be determined as two distinct two-variable reductions of the rate equations in the limit of large capture rates, depending on their relative values. The first case leads to the rate equations for quantum well lasers, exhibiting relaxation oscillations dynamics. The second case corresponds to GNRs nearly saturated by the carriers and is characterized by the absence of relaxation oscillations. Our results here demonstrated that GNR-array as gain material embedded into a high finesse microcavity can serve as an ultralow lasing threshold nanolaser with promising applications ranging widely from optical fiber communi- cation with increasing data processing speed to digital optical recording and biology spectroscopy.

关键词： graphene nanoribbon graphene nanoribbon laser laser theory laser model

Graphene based functional devices: A short review

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Frontiers of physics 2019年第1期14卷 23-42页

作者： Rong Wang Xin-Gang Ren Ze Yan Li-Jun Jiang Wei E. I. Sha guang-cun shan Department of Electrical and Electronic Engineering The University of Hong Kong Pokfulam Road Hong Kong China Key Laboratory of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei 230039 China School of Instrumentation Science & Opto-electronics Engineering Beihang University Beijing 100191 China Key Laboratory of Micro-nano Electronic Devices and Smart Systems of Zhejiang Province College of Information Science & Electronic Engineering Zhejiang University Hangzhou 310027 China California NanoSystem Institute and Department of Chemistry & Biochemistry University of California Los Angeles CA 90095 USA

Graphene is an ideal 2D material system bridging electronic and photonic devices. It also breaks the fundamental speed and size limits by electronics and photonics, respectively. Graphene offers multiple functions of signal transmission, emission, modulation, and detection in a broad band, high speed, compact size, and low loss. Here, we have a brief view of graphene based functional devices at microwave, terahertz, and optical frequencies. Their fundamental physics and computational models were discussed as well.

关键词： graphene terahertz antenna microwave

Static recrystallization behaviors and mechanisms of 7Mo super-austenitic stainless steel with undissolved sigma precipitates during double-stage hot deformation

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Journal of Iron and Steel Research(International) 2024年第2期31卷 475-487页

作者： Shi-guang Xu Jin-shan He Run-ze Zhang Fu-cheng Zhang Xi-tao Wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Science)Jinan250353ShandongChina

Static recrystallization(SRX)behaviors and corresponding recrystallization mechanisms of 7Mo super-austenitic stainless steel were studied under different deformation conditions.The order of influence of deformation parameters on static recrystallization behaviors,from high to low,is followed by temperature,first-stage strain and strain rate.Meanwhile,the effect of holding time on static recrystallization behaviors is significantly controlled by temperature.In addition,with the increase in temperature from 1000 to 1200°C,the static recrystallization mechanism evolves from discontinuous static recrystallization and continuous static recrystallization(cSRX)to metadynamic recrystallization and cSRX,and finally to cSRX.The cSRX exists at all temperatures.This is because high stacking fault energy(56 mJ m−2)promotes the movement of dislocations,making the deformation mechanism of this steel is dominated by planar slip of dislocation.Large undissolved sigma precipitates promote static recrystallization through particle-stimulated nucleation.However,small strain-induced precipitates at grain boundaries hinder the nucleation of conventional SRX and the growth of recrystallized grains,while the hindering effect decreases with the increase in temperature.

关键词： 7Mo super-austenitic stainless steel Double-stage hot deformation Conventional static recrystallization Metadynamic recrystallization Strain-induced precipitation

Amorphous NiMo_(3)S_(13)/nickel foam integrated anode for lithium-ion batteries

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Tungsten 2024年第2期6卷 438-446页

作者： Ming-Xin Shi Min Wu shan-shan Xiao shan-Ping Liu Rui-Qi Yao Ying-Qi Li Yong-Hui Wang Yang-guang Li Hua-Qiao Tan Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Faculty of ChemistryNortheast Normal UniversityChangchun 130024China School of Materials Science and Engineering Jilin Jianzhu UniversityChangchun 130118China Institute Charles Gerhardt Montpellier Universite de MontpellierCentre National de la Recherche Scientifi quePlace E.Bataillon34095 Montpellier Cedex 05France

Although crystalline anode materials with long-range ordered lattice structure are in favor of facilitating the electron transfer,their structures are easily disrupted during long-term cycling due to the continuous embedding/de-embedding of lithium ions.In contrast,the amorphous materials have abundant defects and lithium ion storage sites,refl ecting a superior reaction kinetics and long-term cycling stability.Here,we synthesize an integrated hybrid anode by in-situ loading amorphous NiMo_(3)S_(13)nanosheets on nickel foam substrate.Benefi ting from the introduction of Ni^(2+)that amorphizes the molybdenumsulfur clusters,the assembled lithium ion battery based on the integrated NiMo_(3)S_(13)/nickel foam anode delivers a specifi c capacity up to 1659 mA·h·g^(−1)at a current density of 0.6 A·g^(−1)and exhibits superior rate/cycling performance.

关键词： Molybdenum-sulfur clusters Amorphous Integrated anode Crystalline Lithium-ion batteries

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Steric hindrance modulation of hexaazatribenzanthraquinone isomers for high-capacity and wide-temperature-range aqueous proton battery

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National Science Review 2024年第4期11卷 271-282页

作者： Mingsheng Yang Yuxin Hao Bei Wang Yan Wang Liping Zheng Rui Li Huige Ma Xinyu Wang Xiaoming Jing Hongwei Li Mengxiao Li Zhihui Wang Yujie Dai guangcun shan Mingjun Hu Jun Luo Jun Yang School of Materials Science and Engineering Beihang University Beijing Institute of Nanoenergy &Nanosystems Chinese Academy of Sciences Center on Nanoenergy Research School of Physical Science & TechnologyGuangxi University School of Chemistry and Chemical Engineering Center on Nanoenergy Research Guangxi University School of Instrumentation Science and Opto-electronics Engineering Beihang University ShenSi Lab Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of China

Organic materials with rich active sites are good candidates of high-capacity anodes in aqueous batteries,but commonly low utilization of active sites limits their capacity.Herein,two isomers,symmetric and asymmetric hexaazatribenzanthraquinone（s-HATBAQ and a-HATBAQ）,with rich active sites have been synthesized in a controllable manner.It has been revealed for the first time that a sulfuric acid catalyst can facilitate the stereoselective formation of s-HATBAQ.Attributed to the reduced steric hindrance in favor of proton insertion as well as the amorphous structure conducive to electrochemical dynamics,s-HATBAQ exhibits 1.5 times larger specific capacity than a-HATBAQ.Consequently,the electrode of s-HATBAQ with50% reduced graphene oxide（s-HATBAQ-50%rGO） delivers a record high specific capacity of405 mAh g-1in H2SO4electrolyte.Moreover,the assembled MnO2//s-HATBAQ-50%rGO aqueous proton full batteries show an exceptional cycling stability at 25℃ and can maintain ～92% capacity after1000 cycles at 0.5 A g-1at-80℃.This work demonstrates the controllable synthesis of isomers,showcases a wide-temperature-range prototype proton battery and highlights the significance of precise mole cular structure modulation in organic energy storage.

关键词： stereoisomers steric effect aqueous battery super cycling stability ultra-low temperature proton battery

Porous Ti_(3)C_(2)T_(x) MXene nanosheets sandwiched between polyimide fiber mats for electromagnetic interference shielding

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Nano Research 2024年第3期17卷 2070-2078页

作者： Wenhao Liang Juntao Wu shan Zhang Pei-Yan Zhao Yi Cong Yongqiang Guo guang-Sheng Wang Key Laboratory of Bioinspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191China

With the rapid development of wireless communication technology and electronic devices,the issue of electromagnetic interference(EMI)is becoming increasingly severe.Developing a new and flexible electromagnetic interference shielding material has become a challenging task.Here,a sandwich-structured EMI shielding composite film was prepared using electrospinning and vacuum filtration methods.In this process,a porous MXene was synthesized through a reaction with cobalt acetate and served as the intermediate layer in the composite film to shield electromagnetic waves.The electrospun polyimide(PI)fibers were used as the top and bottom layers of the composite film,which can protect the porous MXene from oxidation.This lightweight and flexible composite film integrates electromagnetic interference shielding and thermal insulation capabilities,showing excellent comprehensive performance.The composite film achieves an EMI shielding effectiveness of 48.8 dB in X-band(8.2–12.4 GHz),and absolute shielding effectiveness of the composite film reached a satisfying 4142.43(dB·cm^(2))/g.Owing to the design of a multi-layer porous structure,the density of the composite film is 0.65 g/cm3.Furthermore,the thermal conductivity of the film is 0.042 W/(m·K)due to the clamping of electrospun PI fibers,showing excellent thermal insulation performance.Additionally,the composite film exhibits excellent high and low-temperature resistance.In summary,this work provides a feasible strategy for preparing a lightweight polymer-based EMI shielding film.

关键词： porous MXene polyimide electromagnetic interference shielding thermal insulation

基于领域知识辅助的机器学习方法对软磁金属玻璃性能的预测

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Transactions of Nonferrous Metals Society of China 2023年第1期33卷 209-219页

作者：李鑫单光存赵鸿滨石燦鴻北京航空航天大学仪器科学与光电工程学院北京100191 香港城市大学材料科学与工程系香港特别行政区有研科技集团有限公司智能传感功能材料国家重点实验室北京100088

提出一种领域知识辅助的机器学习方法,实现对软磁金属玻璃饱和磁化强度(B_(s))和临界尺寸(D_(max))的预测。基于公开的实验数据,建立软磁合金数据库。提出一个通用的特征空间,适用于面向不同预测任务的机器学习模型训练。结果表明,机器... 详细信息

提出一种领域知识辅助的机器学习方法,实现对软磁金属玻璃饱和磁化强度(B_(s))和临界尺寸(D_(max))的预测。基于公开的实验数据,建立软磁合金数据库。提出一个通用的特征空间,适用于面向不同预测任务的机器学习模型训练。结果表明,机器学习模型的预测能力比基于物理知识的估计方法精度更高。此外,领域知识辅助的特征选择可在有效减少特征数量的同时,不显著降低模型的预测精度。最后,对软磁金属玻璃临界尺寸的二分类预测进行讨论。

关键词：金属玻璃软磁性玻璃形成能力机器学习材料描述符

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