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Rare Metals 2023年第11期42卷 3614-3621页

作者： Xiao-Kun Fan Wen Chen Yun-Hua Zhu Wen-Hui Wang Bay Area Center for Electron Microscopy Songshan Lake Materials LaboratoryDongguan523808China School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhen518055China State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai200092China

Developing highly active and stable Pt-based nanocatalysts towards the ethanol oxidation reaction(EOR)is still a challenge for the commercialization of direct ethanol fuel cells.Herein,SnO_(2) patched ultrathin PtRhM(... 详细信息

关键词： nanowires electronic structure

electronic SPECTRA OF HYPOCRELLIN A, B AND THEIR DERIVATIVES

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Science China Chemistry 1990年第1期33卷 18-26页

作者：第五振军蒋丽金张曼华 Institute of Photographic Chemistry Academia Sinica Belling 100012 PRC

In this paper, the electronic spectra of hypocrellin A and B (HA and HB) are studied in detail. It has been proved that their three visible absorption bands come respectively from the ππ transition of their conjugated systems and intramolecular proton transfer. In dilute solutions, their fluorescence spectra consist of the fluorescence peak of the neutral monomolecule and that of the zwitter-ions that are formed through proton transfer of excited states. In concentrated solution, the longer wavelength emission band is composed of the overlapped fluorescence peaks of zwitter-ions and excimers. The fluorescence spectra of the crystalline hypocrellin A and B consist of the fluorescence peaks of zwitter-ions and excimers and the fluorescence of neutral monomolecules could not be observed. Their relative intensities are closely related to the excitation wavelength.

关键词： hypocrellin A and B perylene quinone electronic spectrum.

electronic structure and thermal properties of bulk and nano-layer of TAlO2（T=Cu,Ag and Au） delafossite oxides

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Rare Metals 2019年第10期38卷 905-913页

作者： Hossein Asghar Rahnamaye Aliabad Zahra Sabazadeh Azam Abareshi Department of Physics Hakim Sabzevari University

In this paper,we report the effect of temperature and carrier concentrations on the structural,electronic and thermoelectric(TE) properties of TAlO2(T=Cu,Ag and Au) compounds in the bulk and nano-layer structures using full potential-linearized augmented plane wave(FPLAPW) method combined with Boltzmann transport theory.The results show that the TE properties are controlled by the temperature and carrier concentrations.P-type doping of TAlO2(T=Cu,Ag and Au) compounds has better TE figure of merit(ZT) than n-type doping.High ZT of 0.984 is achieved for the bulk structure of the AgAlO2 compound,while it is about 1.234 for the nano-layer structure.Hence,among these compounds,the nano-layer of AgAlO2 is a good candidate for TE applications.

关键词： electronic and thermoelectric materials Bulk and nano-layer Density functional theory(DFT)calculations

electronic structure of exfoliated millimeter-sized monolayer WSe2 on silicon wafer

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Nano Research 2019年第12期12卷 3095-3100页

作者： Wenjuan Zhao Yuan Huang Cheng Shen Cong Li Yongqing Cai Yu Xu Hongtao Rong Qiang Gao Yang Wang Lin Zhao Lihong Bao Qingyan Wang Guangyu Zhang Hongjun Gao Zuyan Xu Xingjiang Zhou Guodong Liu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China Beijing Academy of Quantum Information Sciences Beijing 100193China

The mono layer WSe2 is in teresting and important for future application in nanoelectronics,spintronics and valleytronics devices,because it has the largest spin splitting and Ion gest valley coherence time among all the known monolayer transition-metal dichalcogenides(TMDs).Toobtain the large-area monolayer TMDs'crystal is the first step to manu facture scalable and high-performance electronic devices.In this letter,we have successfully fabricated millimeter-sized mono layer WSe2 single crystals with very high quality,based on our improved mecha nicalexfoliation method.With such superior samples,using standard high resolution angle-resolved photoemission spectroscopy,we didcomprehe nsive electronic band structure measurements on our mono layer WSe2.The overall band features point it to be a 1.2 eV direct bandgap semico nductor.Its spin splitting of the valence band at K point is found as 460 meV,which is 30 meV less than the corresponding band splitting in its bulk counterpart.The effective hole masses of valence bands are determined as 2.344 me atГ,and 0.529 me as well as 0.532 meat K for the upper and lower branch of splitting ban ds,respectively.And screening effect from substrate is shown to substa ntially impact onthe electronic properties.Our results provide importa nt insights into band structure engineering in mono layer TMDs.Our mono layer WSe2 crystals may constitute a valuable device platform.

关键词： transition-metal dichalcogenides WSe2 monolayer electronic structure angle-resolved photoemission spectroscopy

electronic Nose and Its Applications: A Survey

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International Journal of Automation and computing 2020年第2期17卷 179-209页

作者： Diclehan Karakaya Oguzhan Ulucan Mehmet Turkan Department of Electrical and electronics Engineering Izmir University of EconomicsIzmir 35330Turkey

In the last two decades,improvements in materials,sensors and machine learning technologies have led to a rapid extension of electronic nose(EN)related research topics with diverse applications.The food and beverage industry,agriculture and forestry,medicine and health-care,indoor and outdoor monitoring,military and civilian security systems are the leading fields which take great advantage from the rapidity,stability,portability and compactness of ENs.Although the EN technology provides numerous benefits,further enhancements in both hardware and software components are necessary for utilizing ENs in practice.This paper provides an extensive survey of the EN technology and its wide range of application fields,through a comprehensive analysis of algorithms proposed in the literature,while exploiting related domains with possible future suggestions for this research topic.

关键词： Artificial intelligence machine learning pattern recognition electronic nose(EN) sensors technology

electronic and mechanical responses of two-dimensional HfS2,HfSe2,ZrS2,and ZrSe2 from first-principles

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 486-494页

作者： Mohammad SALAVATI Institute of Structural Mechanics Bauhaus-Universitat WeimarD-99423 WeimarGermany

During the last decade, numerous high-quality two-dimensional (2D) materials with semiconducting electronic character have been synthesized. Recent experimental study (Sci. Adv. 2017;3: el700481) nevertheless confirmed that 2D ZrSe2 and HfSe2 are among the best candidates to replace the silicon in nanoelectronics owing to their moderate band-gap. We accordingly conducted first-principles calculations to explore the mechanical and electronic responses of not only ZrSe2 and HfSe2, but also ZrS? and HfS? in their single-layer and free-standing form. We particularly studied the possibility of engineering of the electronic properties of these attractive 2D materials using the biaxial or uniaxial tensile loadings. The comprehensive insight provided concerning the intrinsic properties of HfS2, HfSe2, ZrS2, and ZrSc? can be usefiil for their future applications in nanodevices.

关键词： 2D materials mechanical electronic DFT

electronic structure and flotability of gold-bearing pyrite:A density functional theory study

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Journal of Central South University 2017年第10期24卷 2288-2293页

作者：刘丹王伊杰先永骏文书明 State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization(Kunming University of Science and Technology) Kunming 650093China

Various incorporation of Au in pyrite and its effects on the geometrical structure,electronic structure and flotability of pyrite were theoretically investigated and fully discussed by performing density functional theory(DFT).The calculated incorporation energy shows that gold would most likely exist in pyrite via incorporating into interstitial lattice sites in the absence of As impurity.As a result of incorporated Au,the covalence levels of the S—Fe and S—S bonds are changed,and the tonicity of Au—S bonds and antibonding of Au—Fe bonds are found to form in the pyrite,which would change the natural flotability of pyrite.The Au impurity energy levels are introduced into the energy band and result in the transformation of pyrite semiconductivity type.The calculated band-gap value suggests that the incorporated Au significantly decreases pyrite semiconductivity level,which enhances the formation and the adsorption stability of dixanthogen during pyrite flotation.The DOS results reveal that the stability and depression difficulty level of pyrites increases in the following order:Fe_(32)S_(63)As

关键词： pyrite gold density functional theory electronic structure flotability

electronic Structure and Optical Properties of K2Ti6O13 Doped with Transition Metal Fe or Ag

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Chinese Journal of Chemical Physics 2018年第3期31卷 318-324,368页

作者： Heng-li Chen Hong-yan Lu Yu-min Qi Peng Jin School of Material Science and Engineering Hebei University of TechnologyTianjin 300130China School of Physics and electronic Information Huaibei Normal UniversityHuaibei 235000China

Based on the experimental study of the optical properties of K2Ti6O13 doped with Fe or Ag,their electronic structures and optical properties are studied by the rst-principles method based on the density functional theory(DFT).The calculated optical properties are consis-tent with the experiment results.K2Ti6O13 doped with substitutional Fe or Ag has isolated impurity bands mainly stemming from the hybridization by the Fe 3d states or Ag 4d states with Ti 3d states and O 2p states and the band gap becomes narrower,the absorption edge of K2Ti6O13 thus has a clear red shift and the absorption of visible light can be realized after doping.For Fe-doped K2Ti6O13,the impurity bands are in the middle of the band gap,suggesting that they can be used as a bridge for valence band electrons transition to the conduction band.For Ag-doped K2Ti6O13,the impurity bands form a shallow accep-tor above the valence band and can reduce the recombination rate of photoexcited carriers.The experimental and calculated results are signicant for the development of K2Ti6O13 materials that have absorption under visible light.

关键词： First-principles Doping electronic structures Optical properties

electronic structure and optical properties of the scintillation material wurtzite ZnS(Ag)

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Nuclear Science and Techniques 2017年第3期28卷 35-41页

作者： Dong-Yang Jiang Zheng Zhang Rui-Xue Liang Zhi-Hong Zhang Yang Li Qiang Zhao Xiao-Ping Ouyang Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy School of Nuclear Science and EngineeringNorth China Electric Power University Beijing 102206China School of Electrical and electronic Engineering North China Electric Power University Beijing 102206 China Northwest Institute of Nuclear Technology Xi’an 710024China School of Materials Science and Engineering Xiangtan University Xiangtan 411105 China

In order to investigate the effect of Ag doping(ZnS(Ag)) and Zn vacancy(V_(Zn)) on the alpha particle detection performance of wurtzite(WZ) ZnS as a scintillation cell component, the electronic structure and optical properties of ZnS, ZnS(Ag), and V_(Zn)were studied by firstprinciple calculation based on the density functional theory. The results show that the band gaps of ZnS, ZnS(Ag),and V_(Zn)are 2.17, 1.79, and 2.37 eV, respectively. Both ZnS(Ag) and V_(Zn)enhance the absorption and reflection of the low energy photons. A specific energy, about 2.9 eV,leading to decrease of detection efficiency is observed. The results indicate that Ag doping has a complex effect on the detection performance. It is beneficial to produce more visible light photons than pure WZ ZnS when exposed to the same amount of radiation, while the increase of the absorption to visible light photons weakens the detection performance. Zn vacancy has negative effect on the detection performance. If we want to improve the detection performance of WZ ZnS, Ag doping will be a good way,but we should reduce the absorption to visible light photons and control the number of Zn vacancy rigorously.

关键词： Wurtzite ZnS electronic structure Optical properties First-principle

electronic structures and properties of pure vanadium

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中国有色金属学会会刊：英文版 1999年第3期9卷 446-450页

作者： He Yu(贺昱) Xie Youqing(谢佑卿) Peng Kun(彭坤) Liu Xinbi(刘心笔) Cent S Univ Technol Dept Mat Sci & Engn Changsha 41083 Peoples R China

By the one atom theory the electronic structure of bcc V has been determined to be [Ar](3d n) 1.799 8 (3d c) 2.657 8 (4S c) 0.171 1 (4s f) 0.371 3 . According to this electronic structure of bcc V, its potential curve, cohesive energy, lattice parameter, elasticity and linear thermal expansion coefficient were calculated. The electronic structures of the primary state crystals of fcc V, hcp V and the primary state liquid—V have also been studied.

关键词： vanadium electronic structure physical properties