Advances in Condensed Matter Physics最新文献_第9页

Thermal Conductivity of Graphitic Carbon Nitride Nanotubes: A Molecular Dynamics Study 石墨氮化碳纳米管的热导率:分子动力学研究

IF 1.5 4区物理与天体物理

Advances in Condensed Matter Physics Pub Date : 2021-12-15 DOI: 10.1155/2021/7188175

Hui Guo, Chunqing Huo, Liang Yang, Shiwei Lin

引用次数: 2

First-Principles Investigation of Structural, Electronic, and Room Temperature Ferromagnetism in Si-Doped Monolayer BN si掺杂单层BN的结构、电子和室温铁磁性第一性原理研究

IF 1.5 4区物理与天体物理

Advances in Condensed Matter Physics Pub Date : 2021-11-30 DOI: 10.1155/2021/5422065

Ahemedin Abedea Ajaybu, Sintayehu Mekonnen Hailemariam

引用次数: 2

Investigation of Structural and Optical Properties of ZnO Thin Films Grown on Different Substrates by Mist-CVD Enhanced with Ozone Gas Produced by Corona Discharge Plasma 电晕放电等离子体产生的臭氧气体增强雾-气相沉积法生长在不同衬底上的ZnO薄膜的结构和光学性能研究

IF 1.5 4区物理与天体物理

Advances in Condensed Matter Physics Pub Date : 2021-11-27 DOI: 10.1155/2021/1130829

E. Kutlu-Narin, P. Narin, S. B. Lişesivdin, B. Sarikavak-Lisesivdin

{"title":"Investigation of Structural and Optical Properties of ZnO Thin Films Grown on Different Substrates by Mist-CVD Enhanced with Ozone Gas Produced by Corona Discharge Plasma","authors":"E. Kutlu-Narin, P. Narin, S. B. Lişesivdin, B. Sarikavak-Lisesivdin","doi":"10.1155/2021/1130829","DOIUrl":"https://doi.org/10.1155/2021/1130829","url":null,"abstract":"This study focuses on the growth and physical properties of ZnO thin films on different substrates grown by mist-CVD enhanced with ozone (O3) gas produced by corona discharge plasma using O2. Here, O3 is used to eliminate the defects related to oxygen in ZnO thin films. ZnO thin films are grown on amorphous soda-lime glass (SLG) and single crystals SiO2/Si (100) and c-plane Al2O3 substrates at 350°C of low growth temperature. All ZnO thin films show dominant (0002) diffraction peaks from X-ray diffraction (XRD). As expected, full width at half maximum (FWHM) of (0002) is decreasing in ZnO thin films on single-crystal substrates, especially c-Al2O3 due to similar crystal structure. It is found that the strain in the films is lowest in ZnO/c-Al2O3. The surface morphologies of the thin films are studied with atomic force microscopy (AFM) and scanning electron microscopy (SEM) measurements. Grown ZnO films have a hexagonal and triangular nanostructure with different nanostructure sizes depending on the used substrate types. The calculated surface roughness is dramatically decreased in ZnO/c-Al2O3 compared to the other grown structures. The confocal Raman measurements show the E2(H) peak of ZnO thin films at 437 cm−1. It is suggested that O3 gas produced by corona discharge plasma using O2 can be useful to obtain better crystal quality and physical properties in ZnO thin films.","PeriodicalId":7382,"journal":{"name":"Advances in Condensed Matter Physics","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2021-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88666638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

First-Principles Calculation of Conductivity of Ce-C Codoped SnO2 Contacts Ce-C共掺杂SnO2触点电导率的第一性原理计算

IF 1.5 4区物理与天体物理

Advances in Condensed Matter Physics Pub Date : 2021-11-22 DOI: 10.1155/2021/4346979

Can Ding, Zhenjiang Gao, Xing Hu, Zhao Yuan

{"title":"First-Principles Calculation of Conductivity of Ce-C Codoped SnO2 Contacts","authors":"Can Ding, Zhenjiang Gao, Xing Hu, Zhao Yuan","doi":"10.1155/2021/4346979","DOIUrl":"https://doi.org/10.1155/2021/4346979","url":null,"abstract":"The contact is the core element of the vacuum interrupter of the mechanical DC circuit breaker. The electrical conductivity and welding resistance of the material directly affect its stability and reliability. AgSnO2 contact material has low resistivity, welding resistance, and so on. This material occupies an important position of the circuit breaker contact material. This research is based on the first-principles analysis method of density functional theory. The article calculated the lattice constant, enthalpy change, energy band, electronic density of state, charge density distribution, population, and conductivity of Ce, C single-doped, and Ce-C codoped SnO2 systems. The results show that Ce, C single doping, and Ce-C codoping all increase the cell volume and lattice constant. When the elements are codoped, the enthalpy change is the largest, and the thermal stability is the best. It has the smallest bandgap, the most impurity energy levels, and the least energy required for electronic transitions. The 4f orbital electrons of the Ce atom and the 2p orbital electrons of C are the sources of impurity energy near the Fermi level. When the elements are codoped, more impurity energy levels are generated at the bottom of the conduction band and the top of the valence band. Its bandgap is reduced so conductivity is improved. From the charge density and population analysis, the number of free electrons of Ce atoms and C atoms is redistributed after codoping. It forms a Ce-C covalent bond to further increase the degree of commonality of electrons and enhance the metallicity. The conductivity analysis shows that both single-doped and codoped conductivity have been improved. When the elements are codoped, the conductivity is the largest, and the conductivity is the best.","PeriodicalId":7382,"journal":{"name":"Advances in Condensed Matter Physics","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2021-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75648362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impurity Substitution Enhances Thermoelectric Figure of Merit in Zigzag Graphene Nanoribbons 杂质取代提高之字形石墨烯纳米带的热电优值

IF 1.5 4区物理与天体物理

Advances in Condensed Matter Physics Pub Date : 2021-10-31 DOI: 10.1155/2021/8110754

Saeideh Ramezani Akbarabadi, Mojtaba Madadi Asl

{"title":"Impurity Substitution Enhances Thermoelectric Figure of Merit in Zigzag Graphene Nanoribbons","authors":"Saeideh Ramezani Akbarabadi, Mojtaba Madadi Asl","doi":"10.1155/2021/8110754","DOIUrl":"https://doi.org/10.1155/2021/8110754","url":null,"abstract":"The thermoelectric properties of zigzag graphene nanoribbons (ZGNRs) are sensitive to chemical modification. In this study, we employed density functional theory (DFT) combined with the nonequilibrium green’s function (NEGF) formalism to investigate the thermoelectric properties of a ZGNR system by impurity substitution of single and double nitrogen (N) atoms into the edge of the nanoribbon. N-doping changes the electronic transmission probability near the Fermi energy and suppresses the phononic transmission. This results in a modified electrical conductance, thermal conductance, and thermopower. Ultimately, simultaneous increase of the thermopower and suppression of the electron and phonon contributions to the thermal conductance leads to the significant enhancement of the figure of merit in the perturbed (i.e., doped) system compared to the unperturbed (i.e., nondoped) system. Increasing the number of dopants not only changes the nature of transport and the sign of thermopower but also further suppresses the electron and phonon contributions to the thermal conductance, resulting in an enhanced thermoelectric figure of merit. Our results may be relevant for the development of ZGNR devices with enhanced thermoelectric efficiency.","PeriodicalId":7382,"journal":{"name":"Advances in Condensed Matter Physics","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2021-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75207069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Density Functional Theory Study on the Effect of Isomorphic Substitution of FAU Molecular Sieve on N2 Adsorption Performance FAU分子筛同构取代对N2吸附性能影响的密度泛函理论研究

IF 1.5 4区物理与天体物理

Advances in Condensed Matter Physics Pub Date : 2021-10-22 DOI: 10.1155/2021/2370816

Mengya Wang, R. Cao, Jiezhen Xia, Luchao Zhao, Yong Li, Qimi Ciren, D. Zhao, Shifeng Wang, Chunmiao Du, Qi Wu

{"title":"Density Functional Theory Study on the Effect of Isomorphic Substitution of FAU Molecular Sieve on N2 Adsorption Performance","authors":"Mengya Wang, R. Cao, Jiezhen Xia, Luchao Zhao, Yong Li, Qimi Ciren, D. Zhao, Shifeng Wang, Chunmiao Du, Qi Wu","doi":"10.1155/2021/2370816","DOIUrl":"https://doi.org/10.1155/2021/2370816","url":null,"abstract":"Low pressure and anoxia are the main characteristics of the environment in the Tibetan Plateau, which means people living there have a large demand for oxygen to reduce the symptoms of altitude sickness. Pressure swing adsorption (PSA) is a competitive oxygen production technology in plateau areas, which relies on the molecular sieves for the separation of N2 and O2 in industry and portable medical equipment. The adsorption characteristics of the Faujasite-type (FAU) molecular sieves, as one kind of the most widely used adsorbents for O2 production, depend on the properties, amount, and distribution of the skeleton cations and atoms. In this paper, we explore the isomorphic substitution effect on the adsorption properties of N2 in FAU molecular sieves using the computational approaches based on the density functional theory (DFT). The structural analysis and adsorption energy calculated for the Zn, Ca, and Ga substitutions at the Si/Al skeleton sites in the β-cage structure, the basic unit of FAU molecular sieves, prove that the isomorphic substitution effect can strengthen the adsorption of N2. The Bader charge and density of states analysis validate the formation of electron-deficient holes near the Fermi level and hence strengthen the local polarity of the pore structure and enhance the adsorption of N2 molecules. The work about isomorphic substitution on the FAU molecular sieves might provide an insight into heteroatom isomorphic modification mechanisms and designing excellent air separation materials.","PeriodicalId":7382,"journal":{"name":"Advances in Condensed Matter Physics","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2021-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86835671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of the Crystallographic Perfection and Photoluminescence Spectrum of the Epitaxial Films of (Si2)1-x(GaP)x 0 ≤ x ≤ 1 Solid Solution, Grown on Si and GaP Substrates with the Crystallographic Orientation (111) (Si2)1-x(GaP)x 0≤x≤1固溶体在Si和GaP基底上生长的晶体取向外延膜的晶体完美性和光致发光光谱研究(111)

IF 1.5 4区物理与天体物理

Advances in Condensed Matter Physics Pub Date : 2021-10-18 DOI: 10.1155/2021/3472487

A. Saidov, D. Saparov, Sh. N. Usmonov, A. Kutlimratov, J. M. Abdiev, M. Kalanov, A. Razzakov, A. Akhmedov

{"title":"Investigation of the Crystallographic Perfection and Photoluminescence Spectrum of the Epitaxial Films of (Si2)1-x(GaP)x\u0000 \u0000 \u0000 0\u0000 ≤\u0000 x\u0000 ≤\u0000 1\u0000 \u0000 \u0000 Solid Solution, Grown on Si and GaP Substrates with the Crystallographic Orientation (111)","authors":"A. Saidov, D. Saparov, Sh. N. Usmonov, A. Kutlimratov, J. M. Abdiev, M. Kalanov, A. Razzakov, A. Akhmedov","doi":"10.1155/2021/3472487","DOIUrl":"https://doi.org/10.1155/2021/3472487","url":null,"abstract":"Epitaxial layers of the solid solution of molecular substitution (Si2)1-x(GaP)x (0 ≤ x ≤ 1) on Si (111) and GaP (111) substrates are grown by liquid-phase epitaxy from an Sn solution-melt. Such graded-gap solid solutions allow the integration of well-established silicon technology with the advantages of III-V semiconductor compounds. The structural features, the distribution of the atoms of the components over the thickness of the epitaxial layer, the photoluminescence spectrum of the (Si2)1-x(GaP)x (0 ≤ x ≤ 1) solid solution, and the electroluminescence of the structure n-GaP-n+-(Si2)x (GaP)1-x (0 ≤ x ≤ 0.01) have been investigated. It is shown that the layers of the solid solution have a perfect single-crystal structure with the crystallographic orientation (111), with the size of subcrystallites ∼ 39 ± 1 nm. The epitaxial layer (Si2)1-x(GaP)x (0 ≤ x ≤ 1) is a graded-gap layer with a smoothly and monotonically varying composition from silicon to 100% GaP. The energy levels of atoms of Si2 molecules which are located 1.47 eV below the bottom of the conduction band of gallium phosphide are revealed. Red emission of n-GaP-n+-(Si2)x(GaP)1-x (0 ≤ x ≤ 0.01) structure which is caused by electron transitions with participation of energy levels of Si2 atoms is detected.","PeriodicalId":7382,"journal":{"name":"Advances in Condensed Matter Physics","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80491853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Substrate Temperature-Dependent Structural, Optical, and Electrical Properties of Thermochromic VO2(M) Nanostructured Films Grown by a One-Step Pulsed Laser Deposition Process on Smooth Quartz Substrates 在光滑石英衬底上用一步脉冲激光沉积法生长的热致变色VO2(M)纳米薄膜的结构、光学和电学特性

IF 1.5 4区物理与天体物理

Advances in Condensed Matter Physics Pub Date : 2021-09-06 DOI: 10.1155/2021/7700676

A. Hendaoui

{"title":"Substrate Temperature-Dependent Structural, Optical, and Electrical Properties of Thermochromic VO2(M) Nanostructured Films Grown by a One-Step Pulsed Laser Deposition Process on Smooth Quartz Substrates","authors":"A. Hendaoui","doi":"10.1155/2021/7700676","DOIUrl":"https://doi.org/10.1155/2021/7700676","url":null,"abstract":"Thermochromic M-phase vanadium dioxide VO2(M) films with different morphologies have been grown directly on smooth fused quartz substrates using low deposition rate pulsed laser deposition without posttreatment. When the substrate temperature was increased in the range 450°C–750°C, better (011) texturization of VO2(M) films was observed along with an enhancement of their crystallinity. Morphology evolved from small-grained and densely packed VO2(M) grains at 450°C to less packed micro/nanowires at 750°C. Mechanisms behind the crystallinity/morphology evolution were discussed and correlated with the effect of the temperature on the diffusion of the adatoms as well as on the V5+ valence states content in VO2(M) films. Resistivity measurements as a function of temperature revealed that the insulator-to-metal transition features of VO2(M) films (i.e., transition temperature (TIMT), resistivity variation (ΔR), hysteresis width (ΔH), and transition sharpness (ΔT)) are strongly dependent on the processing temperature. In terms of optical properties, it was found that the open (i.e., porous) structure of the films achieved at high temperature induced an improvement of their luminous transmittance. Simultaneously, the enhancement of the films crystallinity with the temperature resulted in better IR modulation ability. The present contribution provides a one-step process to control the morphology of VO2(M) films grown on smooth quartz substrates for applications as switches, memory devices, and smart windows.","PeriodicalId":7382,"journal":{"name":"Advances in Condensed Matter Physics","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2021-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85592515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Theoretical Study of Excitonic Complexes in GaAs/AlGaAs Quantum Dots Grown by Filling of Nanoholes 纳米孔填充生长GaAs/AlGaAs量子点中激子复合物的理论研究

IF 1.5 4区物理与天体物理

Advances in Condensed Matter Physics Pub Date : 2021-08-30 DOI: 10.1155/2021/3928308

M. Omri, A. Sayari, L. Sfaxi

引用次数: 0

The Relationship between the Structure and Thermal Properties of Bi2O3-ZnO-B2O3 Glass System Bi2O3-ZnO-B2O3玻璃体系结构与热性能的关系

IF 1.5 4区物理与天体物理

Advances in Condensed Matter Physics Pub Date : 2021-08-20 DOI: 10.1155/2021/2321558

S. Lan, Chin-Tung Lee, Y. Lai, C. Chen, Hsi-Wen Yang

{"title":"The Relationship between the Structure and Thermal Properties of Bi2O3-ZnO-B2O3 Glass System","authors":"S. Lan, Chin-Tung Lee, Y. Lai, C. Chen, Hsi-Wen Yang","doi":"10.1155/2021/2321558","DOIUrl":"https://doi.org/10.1155/2021/2321558","url":null,"abstract":"The influence of Bi2O3 and melting temperature on the thermal and structural properties of xBi2O3-(60-x) ZnO-40B2O3 glasses has been investigated in this study. It is expected that these factors can be used to control the degree of reduction of Bi2O3, and the relationship between these factors and the color change of the process for bismuth glass is discussed. Due to high-temperature melting, the bismuth-doped borate glasses have changed into dark/black from original transparent yellow and the light transmittance will decrease, so it is not used in optical applications. The thermal properties of glass are measured by a thermomechanical analyzer (TMA), and the glass structure is analyzed by FTIR and XPS. The results show that the glass is mainly composed of [BiO6] octahedron, [BiO3] triangle, [BO4] tetrahedron, and triangle [BO3] units, and the network of the glass system is mainly bonded by B-O-B, B-O-Zn, B-O-Bi, and Bi-O-Bi. The glass thermal expansion coefficient (CTE) of this glass system increases with the increase of Bi2O3 content, and the O1s nuclear electron binding energy shifts to the lower energy direction with the increase of Bi2O3 addition. In terms of FTIR, as the melting temperature rises, the B-O-B bonding vibration concentration of [BO4] inside the borate glass decreases, and the density of B-O-B bonding vibration of [BO3] increases, Moreover, the increase in melting temperature increases the probability of reducing Bi ions to Bi0, reduces the bonding of Bi-O-B, and increases the bonding of B-O-B, and the CTE also slightly decreases.","PeriodicalId":7382,"journal":{"name":"Advances in Condensed Matter Physics","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2021-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83276617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11