Computational Materials Science最新文献_第5页

Electrical conductivity of graphene/copper composites at lattice scale 石墨烯/铜复合材料在晶格尺度上的电导率

IF 3.1 3区材料科学

Computational Materials Science Pub Date : 2024-08-28 DOI: 10.1016/j.commatsci.2024.113314

{"title":"Electrical conductivity of graphene/copper composites at lattice scale","authors":"","doi":"10.1016/j.commatsci.2024.113314","DOIUrl":"10.1016/j.commatsci.2024.113314","url":null,"abstract":"<div>Graphene/copper composites are potential structure-function integrated materials. Different from previous micro-nano scale composites, graphene/copper lattice-scale composites and their effects on electrical conductivity are investigated in this work. Using the first-principles calculation to explore the effects of different numbers of graphene layers on the properties of graphene/copper composites, it is found that with the increase of graphene layer numbers, the interfacial bonding strength improves, but the electrical properties show a decreasing trend due to the electron scattering and increasing Cu–C layer distance. The single-layer graphene/copper composite has the most excellent electrical properties, with the highest density of states at the Fermi level and the most charge transfer. A series of layered-structural composites at lattice scale are screened, and their electrical properties and dynamic stability are also predicted. These composites rely on metallic bonding to connect copper and carbon atoms, most of which show obvious vertical charge transfer and high conductivity, with short Cu–C layer distance and alternating arrangement of metal layers and hexagonal carbon atoms. CuC2 (derived from MgB2) has the highest average conductivity and dynamic stability and can be considered an ideal lattice-scale composite. The development of new lattice-scale composites is significant for the future research of graphene/copper composites.</div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142088070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Factors influencing the stability of Pt-based ORR electrocatalysts in HT-PEMFCs: A theoretical investigation 影响 HT-PEMFC 中铂基 ORR 电催化剂稳定性的因素：理论研究

IF 3.1 3区材料科学

Computational Materials Science Pub Date : 2024-08-28 DOI: 10.1016/j.commatsci.2024.113309

{"title":"Factors influencing the stability of Pt-based ORR electrocatalysts in HT-PEMFCs: A theoretical investigation","authors":"","doi":"10.1016/j.commatsci.2024.113309","DOIUrl":"10.1016/j.commatsci.2024.113309","url":null,"abstract":"<div>Electrocatalyst stability is a key parameter for commercializing high-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs). Here, we used density functional theory (DFT) to investigate the stability of Pt-based electrocatalysts by calculating the binding energy (ΔEb) of surface Pt atoms under working conditions. Our results show that Pt(111) is more stable than Pt(100) and Pt(110) under vacuum conditions. Stress hurts the stability of Pt(111), regardless of compressive or tensile stress. Most of the transition metals alloyed with Pt improve the stability of Pt(111), especially PtV, PtY, and PtTa, which increase the ΔEb by 0.60–0.70 eV (ΔΔEb). However, the stability of Pt is significantly destroyed under the working conditions of oxygen reduction reaction (ORR). The specific adsorption of ORR intermediates and electrolyte ions decreases the ΔEb of Pt(111) by 0.35–0.95 eV, and the effect of PO43-* is more significant. Furthermore, when the electric field of the electrochemical double layer is coupled with PO43-* specific adsorption, ΔΔEb further increases to 1.12 eV. Our results highlight the importance of the intrinsic ΔEb and the working conditions for the stability of Pt-based electrocatalysts. This work provides important guidelines for the design of stable ORR electrocatalysts for HT-PEMFCs.</div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142088071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electronic structure and theoretical exfoliation of non-van der Waals carbonates into low-dimensional materials: A case of Y2(CO3)3 非范德华碳酸盐的电子结构和低维材料的理论剥离：Y2(CO3)3 的实例

IF 3.1 3区材料科学

Computational Materials Science Pub Date : 2024-08-28 DOI: 10.1016/j.commatsci.2024.113329

{"title":"Electronic structure and theoretical exfoliation of non-van der Waals carbonates into low-dimensional materials: A case of Y2(CO3)3","authors":"","doi":"10.1016/j.commatsci.2024.113329","DOIUrl":"10.1016/j.commatsci.2024.113329","url":null,"abstract":"<div>The unique properties of two-dimensional (2D) materials make them highly versatile for a wide range of applications. Recently, low-dimensional structures obtained from bulk non-van der Waals materials have received particular interest. Yttrium carbonate is an example of such materials which hold the potential for creating 2D structures, however, its fundamental properties have been investigated only rarely. In this work, we demonstrate the possibility of obtaining 2D yttrium carbonate with the tengerite-(Y) structure. The electronic and optical properties of both bulk and two-dimensional Y2(CO3)3·2H2O are investigated using the PBE and HSE06 functionals. While the bulk material is predicted with a bandgap of 7.06 eV at the HSE06 level, the 2D Y2(CO3)3·2H2O material possesses a bandgap of, untypically, 0.4 eV narrower than the bulk material due to surface effects and different stoichiometry. The optical properties reveal that both the bulk and 2D forms are transparent in the visible and near-UV regions positioning them as promising candidates for various optical applications including doping-induced luminescent devices.</div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0927025624005500/pdfft?md5=a9125ab53f9b7fd3f10501b258ded3aa&pid=1-s2.0-S0927025624005500-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142088093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The effects of refractory elements on the properties of quaternary high entropy carbides—A first-principles and experiment study 难熔元素对四元高熵碳化物特性的影响--第一原理和实验研究

IF 3.1 3区材料科学

Computational Materials Science Pub Date : 2024-08-28 DOI: 10.1016/j.commatsci.2024.113324

{"title":"The effects of refractory elements on the properties of quaternary high entropy carbides—A first-principles and experiment study","authors":"","doi":"10.1016/j.commatsci.2024.113324","DOIUrl":"10.1016/j.commatsci.2024.113324","url":null,"abstract":"<div>In this work, the effects of refractory transition metal elements on the properties of quaternary equimolar ratio high entropy carbides composed of ⅣB, ⅤB and ⅥB transition metals and C element were studied by first-principles calculations and experiments.The calculation results show that all 75 kinds of high entropy carbides were thermodynamically and mechanically stable and can be formed spontaneously. Among them, Hf can promote the synthesis of high entropy carbides, while Cr has the opposite effect. In addition, single phase solid solution structures can be formed for all 73 HECs except (TiZrHfCr)C and (ZrHfVCr)C. Thereafter, the mechanical properties of these 75 quaternary HECs were compared. The calculation results show that W, Mo, and Ta have a positive effect on improving the elastic modulus, fracture toughness, hardness and melting point of high entropy carbides, while Cr has the opposite effect. The calculation results of phonon spectra show that the six high entropy carbides represented by (TiHfNbTa)C, (TiVNbTa)C, (TiZrNbTa)C, (TiZrNbCr)C, (TiZrNbMo)C and (TiZrNbW)C have lattice dynamic stability. (TiHfNbTa)C, (TiVNbTa)C, (TiZrNbTa)C, (TiZrNbMo)C and (TiZrNbW)C face-centered cubic high entropy carbides were prepared by spark plasma sintering and the microstructure and properties were tested. The experimental results are basically consistent with the calculated results.</div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142088091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation into the strength of β-Sn/α-CoSn3 and Co/α-CoSn3 interfaces with Ni-doped α-CoSn3 using first-principles calculations 利用第一原理计算研究β-Sn/α-CoSn3 和 Co/α-CoSn3 与掺杂镍的α-CoSn3 的界面强度

IF 3.1 3区材料科学

Computational Materials Science Pub Date : 2024-08-27 DOI: 10.1016/j.commatsci.2024.113310

引用次数: 0

Effect of residual stress on mechanical properties of Triply periodic minimal surface lattice structures in Additive manufacturing 残余应力对增材制造中三重周期性最小表面晶格结构机械性能的影响

IF 3.1 3区材料科学

Computational Materials Science Pub Date : 2024-08-27 DOI: 10.1016/j.commatsci.2024.113318

{"title":"Effect of residual stress on mechanical properties of Triply periodic minimal surface lattice structures in Additive manufacturing","authors":"","doi":"10.1016/j.commatsci.2024.113318","DOIUrl":"10.1016/j.commatsci.2024.113318","url":null,"abstract":"<div>Due to its special porous structure with smooth continuous surface and high specific surface area, the triply periodic minimal surface (TPMS) lattice structure exhibits excellent properties such as strong bearing capacity, high energy absorption rate and good fatigue performance. The residual stresses generated during the additive manufacturing (AM) process can have a significant impact on the mechanical properties of the TPMS structure. In this paper, the AM process of four typical TPMS structures are investigated by the thermal–mechanical coupling model. The mechanism of residual stress generation is analyzed, and an optimized preparation process scheme is proposed to reduce the residual stress. Furthermore, the effects of residual stresses on the mechanical properties of TPMS structures are investigated for different types, volume fractions and compression directions. Results show that the influences of scanning speed and hatch spacing on the residual stress are not significant with constant laser power, but the deposition thickness should be adjusted according to the characteristics of the structure. The residual stress will reduce the elastic modulus and yield strength, while no obvious effect on the plastic behavior is observed. Importantly, the residual stress has the greatest influence on the mechanical properties of I-WP-type among the four investigated types, which becomes more pronounced with the increase of volume fraction. Moreover, the influence of residual stress on the mechanical properties of TPMS structures depends on the compression direction. Our results give a comprehensive understanding of the residual stress distribution and impact on the mechanical properties of TPMS structures, providing guidance to the rational design and optimization of TPMS structures in engineering applications.</div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142083442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pt3Zr alloy as a protective coating against oxidation and hydrogen attack on Zr-based components in nuclear reactors 将 Pt3Zr 合金作为核反应堆中 Zr 基部件的抗氧化和抗氢气侵蚀保护层

IF 3.1 3区材料科学

Computational Materials Science Pub Date : 2024-08-27 DOI: 10.1016/j.commatsci.2024.113313

{"title":"Pt3Zr alloy as a protective coating against oxidation and hydrogen attack on Zr-based components in nuclear reactors","authors":"","doi":"10.1016/j.commatsci.2024.113313","DOIUrl":"10.1016/j.commatsci.2024.113313","url":null,"abstract":"<div>The adsorption of intact and dissociated water molecules on the surfaces of the Pt3Zr alloy and pure Zr have been investigated by means of density functional theory simulations. In each case, a varying amount of water molecules was placed on the surface until saturation coverage was reached. For both surfaces, all the energy barriers for the partial and complete decomposition of water were calculated. The partial dissociation of H2O into OH and H, and the complete dissociation into O and two H atoms are significantly more difficult on Pt3Zr surfaces, as compared to pure Zr surfaces: the dissociative adsorption energies are smaller and the activation barriers for dissociation are larger in Pt3Zr. In addition, the recombination of H atoms into H2 molecules and desorption of those molecules is easier on the Pt3Zr surfaces. The results suggest that the use of the Pt3Zr alloy as a protective coating in Zr-based metallic components used in nuclear reactors can indeed improve their performance, since the alloyed Pt3Zr layers are much more resistant towards oxidation and H attack than pure Zr in the presence of hot water vapor.</div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0927025624005342/pdfft?md5=9338ba8df78318449818be0a01ebc07d&pid=1-s2.0-S0927025624005342-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142083886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Extensive study of droplet dynamics with end-grafted polymer chains in Pickering emulsions: Molecular Dynamics simulation and a generic model derived from the generalized Langevin equation 广泛研究皮克林乳液中带有端接聚合物链的液滴动力学：分子动力学模拟和广义朗之万方程衍生的通用模型

IF 3.1 3区材料科学

Computational Materials Science Pub Date : 2024-08-27 DOI: 10.1016/j.commatsci.2024.113305

{"title":"Extensive study of droplet dynamics with end-grafted polymer chains in Pickering emulsions: Molecular Dynamics simulation and a generic model derived from the generalized Langevin equation","authors":"","doi":"10.1016/j.commatsci.2024.113305","DOIUrl":"10.1016/j.commatsci.2024.113305","url":null,"abstract":"<div>This paper investigates Pickering emulsions (PEs), formed by suspending oil droplets as the dispersed phase in water as the continuous phase using uncharged particles at their interface. To prevent coalescence, the particles are grafted with polymer chains, as emulsifier, not only to provide steric repulsion forces through the excluded volume between monomers floating in water, compensating for the absence of Coulombic repulsive forces but also control emulsion stabilization/destabilization. We combined molecular dynamics (MD) simulations and a generalized Langevin equation (GLE) model to study the dynamics of hairy-droplets using two dynamic quantities: mean square displacement (MSD) and velocity autocorrelation function (VACF). The number of grafted-polymer-chains, <math><mi>f</mi></math>, was the main parameter of interest, while the other parameters of the system were kept constant. A statistical approach was used to estimate theoretical GLE-based model parameters along with their uncertainties, providing insight into the diffusion behavior of these hairy-droplets and specifically addressing the transition between different observed regimes. we capture three specific values of grafted-polymer-chains as, <math><mrow><msub><mrow><mi>f</mi></mrow><mrow><mi>b</mi></mrow></msub><mo>=</mo><mn>47</mn></mrow></math> and <math><mrow><msub><mrow><mi>f</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>=</mo><mn>185</mn></mrow></math> describe the transitions of mushroom-brush conformation of grafted-polymer-chains and viscous-viscoelastic behavior of hairy-droplets, respectively, and <math><mrow><msub><mrow><mi>f</mi></mrow><mrow><mi>g</mi></mrow></msub><mo>=</mo><mn>257</mn></mrow></math> representing the gel-like state number.</div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142083441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Adsorption mechanism of hydroxyl polytridecaaluminum on kaolinite surface: A DFT study 羟基聚十三烷基铝在高岭石表面的吸附机理：DFT 研究

IF 3.1 3区材料科学

Computational Materials Science Pub Date : 2024-08-27 DOI: 10.1016/j.commatsci.2024.113215

{"title":"Adsorption mechanism of hydroxyl polytridecaaluminum on kaolinite surface: A DFT study","authors":"","doi":"10.1016/j.commatsci.2024.113215","DOIUrl":"10.1016/j.commatsci.2024.113215","url":null,"abstract":"<div>The purpose of this study is to investigate the adsorption mechanism of hydroxyl polytridecaaluminum (Al13) on kaolinite (001) and (00 <math><mrow><mover><mrow><mtext>1</mtext></mrow><mrow><mo>¯</mo></mrow></mover></mrow></math>) surfaces during the flocculation of polyaluminum chloride. Active sites of hydroxyl polytridecaaluminum and adsorption sites on the kaolinite surface were determined by frontier orbital and Mulliken charge, and different adsorption models were constructed. Density functional theory was used to calculate these models. The results demonstrate that the adsorption of Al13 on kaolinite (001) and (00 <math><mrow><mover><mrow><mtext>1</mtext></mrow><mrow><mo>¯</mo></mrow></mover></mrow></math>) surfaces all occurs spontaneously, and the adsorption models with the lowest energy on (001) and (00 <math><mrow><mover><mrow><mtext>1</mtext></mrow><mrow><mo>¯</mo></mrow></mover></mrow></math>) surfaces are formed by five and four hydrogen bonds, respectively. Mulliken charge distribution analysis shows that significant electron transfer occurs in both models, with transfer amounts of 1.16 e and 0.54 e, respectively. The analysis of the partial density of states shows that two Al atoms in the two Al–O octahedra in the outer layer of Al13 have certain bonding interactions with the O atoms of the kaolinite surfaces. The calculations indicate that the interactions of Al13 with kaolinite (001) and (00 <math><mrow><mover><mrow><mtext>1</mtext></mrow><mrow><mo>¯</mo></mrow></mover></mrow></math>) surfaces are mainly electrostatic interactions and hydrogen bonding, and the adsorption strength of Al13 on the (001) surface is higher than that on the (00 <math><mrow><mover><mrow><mtext>1</mtext></mrow><mrow><mo>¯</mo></mrow></mover></mrow></math>) surface.</div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142083887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bayesian inverse inference of material properties from microstructure images 根据微观结构图像对材料特性进行贝叶斯反推分析

IF 3.1 3区材料科学

Computational Materials Science Pub Date : 2024-08-24 DOI: 10.1016/j.commatsci.2024.113306

引用次数: 0