Computational Materials Science最新文献

{"title":"Large exciton binding energy in atomically thin Cs3Bi2I9−xClx halide perovskite","authors":"Srihari M. Kastuar,&nbsp;Chinedu E. Ekuma","doi":"10.1016/j.commatsci.2025.113827","DOIUrl":"10.1016/j.commatsci.2025.113827","url":null,"abstract":"<div><div>Two-dimensional lead-free perovskite Cs<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>Bi<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>I<span><math><msub><mrow></mrow><mrow><mn>9</mn></mrow></msub></math></span> has emerged as a promising optoelectronic material due to its unique composition and quantum confinement effects. Herein, we present a comprehensive first-principles computational analysis of the many-body optoelectronic properties arising from the isoelectronic substitution of Cl into the I site in atomically thin Cs<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>Bi<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>I<span><math><msub><mrow></mrow><mrow><mn>9</mn><mo>−</mo><mi>x</mi></mrow></msub></math></span>Cl<span><math><msub><mrow></mrow><mrow><mi>x</mi></mrow></msub></math></span>. By solving the Bethe–Salpeter equation, we reveal the distinct optical properties of these doped and pristine monolayers, characterized by strongly bound excitons within an ultralow dielectric screening environment. Specifically, we demonstrate that the isoelectronic substitution of Cl in Cs<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>Bi<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>I<span><math><msub><mrow></mrow><mrow><mn>9</mn></mrow></msub></math></span> enables significant tunability of quasiparticle states, leading to an unprecedented increase in the exciton binding energy from 1.32 eV to 2.66 eV, and a corresponding increase in the optical gap from the visible to the ultraviolet spectrum. The dominance of these strongly bound excitons in the ground-state properties highlights the substantial potential of these materials for high-efficiency optoelectronic applications, including light-emitting diodes, laser diodes, solar-blind photodetectors, and reconfigurable optical systems.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"253 ","pages":"Article 113827"},"PeriodicalIF":3.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643322","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}

{"title":"Density functional theory examination of surface defects, substitution, and passivation on HgTe (111) surface for applications in colloidal quantum dots","authors":"Jacob D. Eisensmith,&nbsp;Pratik P. Dholabhai","doi":"10.1016/j.commatsci.2025.113838","DOIUrl":"10.1016/j.commatsci.2025.113838","url":null,"abstract":"<div><div>Colloidal quantum dots (CQDs) and especially those of HgTe offer a potential pathway to highly efficient and economical infrared photodetectors. Herein, we utilized first principles density functional theory to examine the chemical and optoelectronic properties of these materials. We demonstrate that an abundant source of trap states on HgTe (111) surfaces are unpassivated mercury atoms at the surface of the nanocrystal. Furthermore, we show that mercury vacancies, which contribute under-coordinated tellurium sites on the surface, do not appear to have an outsized impact on mid-gap states, unlike other II-VI CQD systems. Critical to device engineering, we present a theoretical method for the universal control of the conduction type in HgTe CQDs, regardless of the synthesis employed. Specifically, the substitution of indium into mercury sites at the surface of the nanocrystal induces n-type doping while p-type doping can be obtained through the adsorption of silver on FCC sites on mercury rich surfaces. During this investigation, we also confirm the observation of a ligand dipole dependent Fermi level. While further experimentation is warranted, this could enable higher performing devices with shorter ligands and precisely engineered band alignments.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"253 ","pages":"Article 113838"},"PeriodicalIF":3.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642127","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}

{"title":"atomes: Analysis, visualization, edition and post-processing of 3D atomic scale models","authors":"Sébastien Le Roux","doi":"10.1016/j.commatsci.2025.113805","DOIUrl":"10.1016/j.commatsci.2025.113805","url":null,"abstract":"<div><div><strong>atomes</strong> is a cross-platform open source program developed to analyze, to visualize and to edit/create large three-dimensional atomic scale models. By regrouping advanced analysis techniques, 3D visualization and 3D edition, <strong>atomes</strong> introduces innovative 3D rendering possibilities and intuitive applications of the calculation results. <strong>atomes</strong> also provides an advanced input preparation system for further calculations using well known classical, <em>ab-initio</em> and QM-MM molecular dynamics codes. To prepare the input files for these calculations is likely to be the key, and most complicated step towards MD simulations. <strong>atomes</strong> offers a user-friendly assistant to help and guide the user step by step to achieve this crucial step.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"253 ","pages":"Article 113805"},"PeriodicalIF":3.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643315","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}

{"title":"Multi-task learning of solute segregation energy across multiple alloy systems","authors":"Liang Yuan ,&nbsp;Zongyi Ma ,&nbsp;Zhiliang Pan","doi":"10.1016/j.commatsci.2025.113846","DOIUrl":"10.1016/j.commatsci.2025.113846","url":null,"abstract":"<div><div>Machine learning can effectively model solute segregation energies at various sites within grain boundary networks. However, single-task learning approaches were usually used in the literature work, requiring as many learning tasks as there are alloy systems and reducing efficiency especially when dealing with numerous systems. In this work, we proposed a multi-task learning strategy to simultaneously learn segregation energies across multiple alloy systems within a hyperparameter-sharing architecture by integrating the data sets of these alloys. With appropriate algorithms and data integration methods, the best multi-task models can learn multiple alloy systems as accurately as the best single-task models. This simple strategy works due to the preserved correlation between site features and segregation energy after data integration, despite the change in how the correlation exists that renders some algorithms that work in single-task learning no longer effective in multi-task learning. This work provides an efficient and convenient approach to modeling site-specific solute segregation energy and will assist in the prediction of segregation behavior in alloy design.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"253 ","pages":"Article 113846"},"PeriodicalIF":3.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643323","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}

{"title":"Simulated design of Cu2N/BiOCl for selective synthesis of C2 alcohol products in photocatalytic reduction of CO2 via nitrogen vacancy on modified square copper sites","authors":"Zigeng Wang ,&nbsp;Manman Mu ,&nbsp;Fahim A. Qaraah ,&nbsp;Guoyi Bai ,&nbsp;Xiaohong Yin","doi":"10.1016/j.commatsci.2025.113839","DOIUrl":"10.1016/j.commatsci.2025.113839","url":null,"abstract":"<div><div>The increasing atmospheric CO₂ concentration resulting from fossil fuel combustion has exacerbated global warming. It is imperative to mitigate CO₂ emissions and convert them into valuable chemicals through innovative solutions. Herein, we employ density functional theory (DFT) calculations to design a defective Cu₂N/BiOCl heterostructure incorporating nitrogen vacancies (Nv) for selective photocatalytic CO₂ reduction to C₂ alcohols. The formation of an ohmic contact in this heterostructure significantly facilitates the transfer of photo-generated electrons. Through the introduction of nitrogen vacancies on Cu₂N/BiOCl, two key roles are realized. The first is enhanced reactivity of the square-symmetric copper sites, which promote CO₂ activation and C–C coupling through improved electron density and orbital interactions. The second is the creation of an intensified interfacial electric field at the BiOCl-Cu₂N interface, effectively promoting charge separation while suppressing carrier recombination. This synergistic effect remarkably boosts photocatalytic efficiency and product selectivity toward the production of high-value two-carbon alcohols. This work provides critical insights into the rational design of photocatalysts for CO₂ reduction, addressing key challenges in sustainability and energy applications.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"253 ","pages":"Article 113839"},"PeriodicalIF":3.1,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636644","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}

{"title":"Enhanced tunnel electroresistance in BAs/In2S3 ferroelectric tunnel junction through ferroelectric control of band alignments","authors":"Ruixue Li ,&nbsp;Sicong Zhu ,&nbsp;Jun Ding","doi":"10.1016/j.commatsci.2025.113823","DOIUrl":"10.1016/j.commatsci.2025.113823","url":null,"abstract":"<div><div>We have designed two-dimensional ferroelectric tunnel junctions (FTJs) utilizing BAs/In<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>S<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> van der Waals heterostructures and explored their transport characteristics. At low bias voltage, a pronounced difference in current magnitudes under different polarization states is observed, leading to a giant tunneling electroresistance (TER) ratio of <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>8</mn></mrow></msup><mtext>%</mtext></mrow></math></span>. Analysis of the projected band structures reveals changes in band alignment from type-III to type-I under the ferroelectric polarization reversal. Further discussions indicate that polarization reversal can cause a variation in the total charge transfer, consequently altering the Fermi level’s position in the BAs and In<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>S<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> layers. This alteration results in a transition between metallic and semiconducting states, thus achieving a high TER ratio. These findings imply great potential of high-performance 2D FTJs, which may contribute to the development of non-volatile storage devices and ferroelectric field-effect transistors.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"253 ","pages":"Article 113823"},"PeriodicalIF":3.1,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632038","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}

{"title":"I212121 carbon: An orthorhombic carbon allotrope with superhard properties","authors":"Jiao Cheng ,&nbsp;Shun Zhou ,&nbsp;Weiguo Liu","doi":"10.1016/j.commatsci.2025.113841","DOIUrl":"10.1016/j.commatsci.2025.113841","url":null,"abstract":"<div><div>An <em>I</em>2₁2₁2₁ carbon with an <em>I</em>2₁2₁2₁ space group and an <em>sp3</em> hybridized network are proposed in this work. We conduct a comprehensive investigation of <em>I</em>2₁2₁2₁ carbon using density functional theory, including its structure, elastic properties, elastic anisotropy in elastic moduli, electronic properties, stability, absorption spectra, and X-ray diffraction patterns. Our results show that <em>I</em>2₁2₁2₁ carbon is both mechanically and dynamically stable. The calculated elastic moduli (shear modulus <em>G</em>, bulk modulus <em>B</em>, and Young’s modulus <em>E</em>) of <em>I</em>2₁2₁2₁ carbon are 352 GPa, 325 GPa, and 776 GPa, respectively, which are higher than those of <em>Ima</em>2 C32, Penta-C₂₀, C24-C, and C24-D. <em>I</em>2₁2₁2₁ carbon has a wide indirect bandgap and is identified as a semiconductor. The absorption ability, of <em>I</em>2₁2₁2₁ carbon is slightly superior performance compared to C24-D, T carbon, C24-C, Y carbon, cubane-yne, C10-C, C14-C, and C20-D. <em>I</em>2₁2₁2₁ carbon could be used as an ultraviolet detector. In addition, the elastic anisotropy in the elastic moduli and <em>X</em>-ray diffraction patterns of <em>I</em>2₁2₁2₁ carbon were analyzed.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"253 ","pages":"Article 113841"},"PeriodicalIF":3.1,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632037","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}

{"title":"Hybrid density functional studies of intrinsic defects in Zn2SbN3 for potential solar cell application","authors":"Rumeng Zhao ,&nbsp;Liu Yang ,&nbsp;Xiuli Yang","doi":"10.1016/j.commatsci.2025.113842","DOIUrl":"10.1016/j.commatsci.2025.113842","url":null,"abstract":"<div><div>Zn₂SbN₃ semiconductors with defect-tolerant properties have a simple structure and promise to be useful in a variety of solar energy conversion applications. The calculated results indicate that Zn₂SbN₃ has a band gap of 1.55 eV, which corresponds to the optimal solar energy absorption band gap. In the visible light range, its absorption coefficient can reach up to 10⁴–10⁵ cm⁻¹, which makes it a suitable material for solar photovoltaic applications. Hybrid functional calculations are used to investigate electronic and defect properties. Our research indicates that Sb_Zn, Zn_i, and V_N1 are the most dominant native defects with low formation energy, which means that the experiment is associated with high resistivity. V_N1 has multiple localized defect states in the band gap that play a significant role in photovoltaic properties and can capture free carriers. This study provides a detailed theoretical explanation of the main reason for the inefficiency of nitride semiconductors as solar cell materials. Also, this is a comprehensive theoretical reference that can be used to grow high-quality thin films and other nitride semiconductor solar cells in experiments.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"253 ","pages":"Article 113842"},"PeriodicalIF":3.1,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143629925","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}

{"title":"Research on the influence of uniaxial stress on the properties of PbTiO3 using first-principles","authors":"Yangyang Cheng ,&nbsp;Yali Yi ,&nbsp;Qingwen Kuang ,&nbsp;Xiangcheng Chu ,&nbsp;Herong Jin","doi":"10.1016/j.commatsci.2025.113814","DOIUrl":"10.1016/j.commatsci.2025.113814","url":null,"abstract":"<div><div>As a classic type of ABO₃ ferroelectric ceramic, PbTiO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> is widely applied in fields such as electronic communication and piezoelectric driving. However, the influences of uniaxial stress on its structure, elasticity, and optical properties remain unclear. This study adopted the first-principles method based on density functional theory to investigate the changes in properties like the crystal structure and electronic structure of PbTiO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> under the action of uniaxial tensile and compressive stresses. Based on the time-dependent density functional theory (TD-DFT), the optical properties including the dielectric function, refractive index, reflectivity, absorption coefficient, and energy loss coefficient were calculated. It was found that when the uniaxial compressive stress was approximately 3.7 GPa, the structure transformed from the tetragonal phase to the cubic phase. When the compressive stress reached 4 GPa, it became a direct bandgap semiconductor. The uniaxial tensile stress increased the bandgap value by a maximum of 11.6 %, yet it always remained an indirect bandgap semiconductor. The mechanical properties of PbTiO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> gradually increased with the increase of uniaxial compressive stress, while the uniaxial tensile stress increased its degree of anisotropy. Regarding optical properties, the uniaxial compressive stress increased the static dielectric function and static refractive index, and the uniaxial tensile stress increased the extinction coefficient and electrical conductivity. However, it had a relatively small impact on the energy loss coefficient. This study provides theoretical guidance for understanding the response mechanism of PbTiO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> to stress-induced modulation and for the research and development of high-performance and stable piezoelectric devices.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"253 ","pages":"Article 113814"},"PeriodicalIF":3.1,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143628005","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}

{"title":"Performance of exchange-correlation approximations to density functional theory for rare-earth oxides","authors":"Mary Kathleen Caucci ,&nbsp;Jacob T. Sivak ,&nbsp;Saeed S.I. Almishal ,&nbsp;Christina M. Rost ,&nbsp;Ismaila Dabo ,&nbsp;Jon-Paul Maria ,&nbsp;Susan B. Sinnott","doi":"10.1016/j.commatsci.2025.113837","DOIUrl":"10.1016/j.commatsci.2025.113837","url":null,"abstract":"<div><div>Rare-earth oxides (REOs) are an important class of materials owing to their unique properties, including high ionic conductivities, large dielectric constants, and elevated melting temperatures, making them relevant to several technological applications such as catalysis, ionic conduction, and sensing. The ability to predict these properties at moderate computational cost is essential to guiding materials discovery and optimizing materials performance. Although density functional theory (DFT) is the favored approach for predicting electronic and atomic structures, its accuracy is limited in describing strong electron correlation and localization inherent to REOs. The newly developed strongly constrained and appropriately normed (SCAN) meta-generalized-gradient approximations (meta-GGAs) promise improved accuracy in modeling these strongly correlated systems. We assess the performance of these meta-GGAs on binary REOs by comparing the numerical accuracy of thirteen exchange–correlation approximations in predicting structural, magnetic, and electronic properties. Hubbard <em>U</em> corrections for self-interaction errors and spin–orbit coupling are systematically considered. Our comprehensive assessment offers insights into the physical properties and functional performance of REOs predicted by first-principles and provides valuable guidance for selecting optimal DFT functionals for exploring these materials.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"253 ","pages":"Article 113837"},"PeriodicalIF":3.1,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143621107","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}