Journal of Physics: Materials最新文献_第3页

Molten Glass-Mediated Conditional CVD Growth of MoS2 Monolayers and Effect of Surface Treatment on Their Optical Properties 熔融玻璃介导的 MoS2 单层有条件 CVD 生长及其表面处理对光学特性的影响

Journal of Physics: Materials Pub Date : 2024-05-15 DOI: 10.1088/2515-7639/ad4c05

F. G. Aras, Abdulsalam Aji Suleiman, Amir Parsi, S. Kasirga, Aydan Yeltik

{"title":"Molten Glass-Mediated Conditional CVD Growth of MoS2 Monolayers and Effect of Surface Treatment on Their Optical Properties","authors":"F. G. Aras, Abdulsalam Aji Suleiman, Amir Parsi, S. Kasirga, Aydan Yeltik","doi":"10.1088/2515-7639/ad4c05","DOIUrl":"https://doi.org/10.1088/2515-7639/ad4c05","url":null,"abstract":"\u0000 In the rapidly developing field of optoelectronics, the utilization of transition-metal dichalcogenides with adjustable band gaps holds great promise. MoS2, in particular, has garnered considerable attention owing to its versatility. However, a persistent challenge is to establish a simple, reliable and scalable method for large-scale synthesis of continuous monolayer films. In this paper, we report the growth of continuous large-area monolayer MoS2 films using a glass-assisted chemical vapor deposition (CVD) process. High-quality monolayer films were achieved by precisely controlling carrier gas flow and sulfur vaporization with a customized CVD system. Additionally, we explored the impact of chemical treatment using lithium bistrifluoromethylsulfonylamine (Li-TFSI) salt on the optical properties of monolayer MoS2 crystals. To investigate the evolution of excitonic characteristics, we conditionally grew monolayer MoS2 flakes by controlling sulfur evaporation. We reported two scenarios on MoS2 films and flakes based on substrate-related strain and defect density. Our findings revealed that high-quality monolayer MoS2 films exhibited lower treatment efficiency due to substrate-induced surface strain, whereas defective monolayer MoS2 flakes demonstrated a higher treatment sensitivity a p-doping effect. The Li-TFSI-induced changes in exciton density were elucidated through photoluminescence (PL), Raman, and X-ray photoelectron spectroscopy (XPS) results. Furthermore, we demonstrated treatment-related healing in flakes under variable laser excitation power. The advancements highlighted in our study carry significant implications for the scalable fabrication of diverse optoelectronic devices, potentially paving the way for widespread real-world applications.","PeriodicalId":501825,"journal":{"name":"Journal of Physics: Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140972872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electromechanical strain response of phosphorene nanotubes 磷烯纳米管的机电应变响应

Journal of Physics: Materials Pub Date : 2024-05-15 DOI: 10.1088/2515-7639/ad4c07

Kevin Tran, P. Taylor, Michelle J. S. Spencer

{"title":"Electromechanical strain response of phosphorene nanotubes","authors":"Kevin Tran, P. Taylor, Michelle J. S. Spencer","doi":"10.1088/2515-7639/ad4c07","DOIUrl":"https://doi.org/10.1088/2515-7639/ad4c07","url":null,"abstract":"\u0000 Nanomaterials that undergo structural or other property changes upon application of external stimuli are called stimuli responsive materials and are particularly suited for drug delivery, biosensing or artificial muscle applications. Two-dimensional (2D) black phosphorus is an ideal material for such applications due to its remarkable electromechanical response. Given that one-dimensional (1D) black phosphorus nanotubes (PNTs) are calculated to be energetically stable, it is possible that they can undergo similar electromechanical responses to their 2D counterparts, allowing their potential application as nanochannel devices for drug delivery. Using first-principles density functional theory, we investigated the electromechanical response of different-sized PNTs upon charge injection. Upon hole injection, the diameter of the PNTs expands up to a maximum of 30.2% for a (0,15) PNT that is 0.24 nm in diameter. The PNTs become highly p-doped as the valence band maximum crosses the Fermi level and undergoes switching from a direct to indirect band gap. The mechanism behind the electromechanical response was determined through analysis of the structural deformations, charge density distribution and Bader partial charges. It was shown that injection of charge alters the Young’s Modulus of the PNTs, as hole injection weakens the structural integrity of the nanotube, allowing a greater electromechanical response, with PNT-15 showing the largest decrease in the Young’s Modulus of 15.34%. These findings show that 1D PNTs are promising materials for the development of nanoelectromechanical actuators which could be used for drug delivery, energy harvesting or similar applications.","PeriodicalId":501825,"journal":{"name":"Journal of Physics: Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140975183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Micrometric patterning of a borogermanate glass containing terbium by thermal poling to manage luminescence and second order optical properties 通过热极化对含铽的硼锗玻璃进行微观图案化，以管理发光和二阶光学特性

Journal of Physics: Materials Pub Date : 2024-05-14 DOI: 10.1088/2515-7639/ad4ba0

J. Orives, L. M. Marcondes, Lara Karam, F. Adamietz, Thierry Cardinal, M. Dussauze, Marcelo Nalin

{"title":"Micrometric patterning of a borogermanate glass containing terbium by thermal poling to manage luminescence and second order optical properties","authors":"J. Orives, L. M. Marcondes, Lara Karam, F. Adamietz, Thierry Cardinal, M. Dussauze, Marcelo Nalin","doi":"10.1088/2515-7639/ad4ba0","DOIUrl":"https://doi.org/10.1088/2515-7639/ad4ba0","url":null,"abstract":"\u0000 Borogermanate glasses containing terbium ions are interesting materials due to their luminescent and magnetic properties. Terbium can present two different oxidation states and the thermal poling technique can be a pertinent way to modulate spatially the oxidation state of this ions. In this work, we demonstrate using a thermo-electrical imprinting process the transfer of micro scaled motifs on the surface of a borogermanate glass containing Tb3+ resulting in a micrometric structuring of the oxidation state of Tb3+/Tb4+ ions. A large change in absorption and luminescence optical properties is observed, arising from the distinct properties of trivalent and tetravalent terbium ions. Correlative micro luminescence, Raman and Second Harmonic Generation measurements were carried out on the patterned poled glass surface. It has demonstrated an accurate concomitant modification of the glass structure accompanying large luminescence changes and the appearance of a second order optical response which could be attributed a localized space charge implantation. These original results demonstrate how a simple electrical process allows managing multi optical properties but also pave the way to induce static electrical functionalities in a magnetic optical glassy system.","PeriodicalId":501825,"journal":{"name":"Journal of Physics: Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140977800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Site-selective cobalt substitution in La–Co co-substituted magnetoplumbite-type ferrites: 59Co-NMR and DFT calculation study La-Co 共取代磁铌铁氧体中钴的位点选择性取代：59Co-NMR 和 DFT 计算研究

Journal of Physics: Materials Pub Date : 2024-04-17 DOI: 10.1088/2515-7639/ad3b6d

Hiroyuki Nakamura, Hiroto Ohta, Ryuya Kobayashi, Takeshi Waki, Yoshikazu Tabata, Hidekazu Ikeno and Christian Mény

{"title":"Site-selective cobalt substitution in La–Co co-substituted magnetoplumbite-type ferrites: 59Co-NMR and DFT calculation study","authors":"Hiroyuki Nakamura, Hiroto Ohta, Ryuya Kobayashi, Takeshi Waki, Yoshikazu Tabata, Hidekazu Ikeno and Christian Mény","doi":"10.1088/2515-7639/ad3b6d","DOIUrl":"https://doi.org/10.1088/2515-7639/ad3b6d","url":null,"abstract":"The La–Co co-substituted magnetoplumbite-type (M-type) ferrites AFe12O19 (A = Ca, Sr and Ba, ion sizes Ca2+ Sr2+ Ba2+) with Co compositions around 0.2 have been subjected to 59Co-NMR. The results show that Co occupies the 4f1, 2a and 12k sites, and that the smaller the A ion, the more Co tends to occupy the 4f1 minority spin site, which is effective in enhancing both uniaxial anisotropy and magnetisation. First-principles total energy calculations based on density functional theory (DFT) of undoped AFe12O19 and a supercell ( of the unit cell) in which 1/96 of Fe3+ is replaced by Co2+ were performed to predict the stable structure and Co occupancy sites. The results show that regardless of A, Co is most stable when it occupies the 4f1 site, followed by the 2a and 12k sites with energy differences on the order of 100 meV, and Co practically does not occupy the 2b and 4f2 sites. As the A ion becomes smaller, the energy difference when Co occupies each Fe site tends to increase, and the Co occupancy of the 4f1 site also increases. The site selectivity of Co can be roughly explained as a result of the difference in uniaxial strain along the c-axis associated with the difference in A. However, the influence of the A ion differs between the R and S blocks and the local strain also has a secondary effect on the Co distribution. Based on these results, the guidelines for improving the performance (anisotropy and magnetisation) of La–Co co-substituted M-type ferrite magnets with a limited amount of Co can be summarised as follows: It is effective to select as small A ions as possible and to post-anneal at low temperature or cool slowly to concentrate Co at the 4f1 site in tetrahedral coordination.","PeriodicalId":501825,"journal":{"name":"Journal of Physics: Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140805682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Interactions of CaO with Pure Mg and Mg-Ca alloys - an in situ synchrotron radiation diffraction study 氧化钙与纯镁和镁钙合金的相互作用--现场同步辐射衍射研究

Journal of Physics: Materials Pub Date : 2024-04-17 DOI: 10.1088/2515-7639/ad3fe9

Björn Wiese, C. Mendis, D. Tolnai, Norbert Hort

引用次数: 0

Structural mode coupling in perovskite oxides using hypothesis-driven active learning 利用假设驱动的主动学习在过氧化物中实现结构模式耦合

Journal of Physics: Materials Pub Date : 2024-04-17 DOI: 10.1088/2515-7639/ad3fea

Ayana Ghosh, Palanichamy Gayathri, Monirul Shaikh, Saurabh Ghosh

{"title":"Structural mode coupling in perovskite oxides using hypothesis-driven active learning","authors":"Ayana Ghosh, Palanichamy Gayathri, Monirul Shaikh, Saurabh Ghosh","doi":"10.1088/2515-7639/ad3fea","DOIUrl":"https://doi.org/10.1088/2515-7639/ad3fea","url":null,"abstract":"\u0000 Finding the ground-state structure with minimum energy is paramount to designing any material. In ABO3-type perovskite oxides with Pnma symmetry, the lowest energy phase is driven by an inherent trilinear coupling between the two primary order parameters such as rotation and tilt with antiferroelectric displacement of the A-site cations as established via hybrid improper ferroelectric mechanism. Conventionally, ﬁnding the relevant mode coupling driving phase transition requires performing ﬁrst-principles computations which is computationally time-consuming as well as expensive. It involves following an intuitive iterative hit and trial method of (a) adding two or multiple mode vectors, (b) evaluating which combination would lead to the ground-state energy. In this study, we show how a hypothesis-driven active learning framework can identify suitable mode couplings within the Landau free energy expansion with minimal information on amplitudes of modes for a series of double perovskite oxides with A-site layered, columnar and rocksalt ordering. This scheme is expected to be applicable universally for understanding atomistic mechanisms derived from various structural mode couplings behind functionalities, for e.g., polarization, magnetization and metal-insulator transitions.","PeriodicalId":501825,"journal":{"name":"Journal of Physics: Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140691628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Anodic alumina/carbon composite films: extraction and characterization of the carbon-containing component 阳极氧化铝/碳复合薄膜：含碳成分的提取和表征

Journal of Physics: Materials Pub Date : 2024-04-17 DOI: 10.1088/2515-7639/ad3b6f

Katsiaryna Chernyakova, Ieva Matulaitienė, Tatjana Charkova, Giedrė Grincienė, Meda Jurevičiūtė, Aurimas Kopūstas, Arūnas Jagminas, Renata Karpicz

{"title":"Anodic alumina/carbon composite films: extraction and characterization of the carbon-containing component","authors":"Katsiaryna Chernyakova, Ieva Matulaitienė, Tatjana Charkova, Giedrė Grincienė, Meda Jurevičiūtė, Aurimas Kopūstas, Arūnas Jagminas, Renata Karpicz","doi":"10.1088/2515-7639/ad3b6f","DOIUrl":"https://doi.org/10.1088/2515-7639/ad3b6f","url":null,"abstract":"Alumina/carbon composites are modern nanomaterials used as adsorbents, catalysts, catalyst supports, supercapacitors, and electrode materials for fuel cells. Among other methods, aluminum anodizing is fairly fast and inexpensive for producing anodic alumina/carbon composites with controllable properties. In the present study, the morphology and composition of carbon-enriched anodic alumina films were obtained during aluminum anodic oxidation in formic acid with ammonium heptamolybdate (C content is ca. 5.0 mass%) or oxalic acid (C content 3.4 mass%) additives. The anodic alumina films have a wide blue fluorescence (FL) in the 400–650 nm wavelength range with a maximum at ca. 490 nm. The FL decay is nonexponential and has an average lifetime of 1.54 and 1.59 ns for ammonium heptamolybdate and oxalic acid additives, respectively. As samples obtained in sulfuric acid (i.e. without carbon) do not possess detectable FL in the 400–650 nm wavelength range, it was concluded that carbon-containing inclusions are responsible for the FL properties of the films. The initial samples were dissolved in the hot aqueous HCl solution and then dialyzed to extract the carbon-containing component. It was shown that the solutions contain nanoparticles of amorphous carbon with a 20–25 nm diameter. Carbon nanoparticles also exhibit an excitation-dependent emission behavior at 280–450 nm excitation wavelengths with average lifetimes of 7.25–8.04 ns, depending on the composition of the initial film. Carbon nanoparticle FL is caused by the core of carbon nanoparticles (CNPs) and various emission centers on their surface, such as carbonyl, carboxyl, and hydroxyl groups. As CNPs could be exceptional candidates for detection technologies, the biocompatibility assays were performed with living COS-7 mammalian cells, showing a minimal negative impact on the living cells.","PeriodicalId":501825,"journal":{"name":"Journal of Physics: Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140612621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Phosphosulfide semiconductors for optoelectronics and solar energy conversion 用于光电子学和太阳能转换的硫化磷半导体

Journal of Physics: Materials Pub Date : 2024-04-16 DOI: 10.1088/2515-7639/ad3aa3

Lena A Mittmann, Andrea Crovetto

{"title":"Phosphosulfide semiconductors for optoelectronics and solar energy conversion","authors":"Lena A Mittmann, Andrea Crovetto","doi":"10.1088/2515-7639/ad3aa3","DOIUrl":"https://doi.org/10.1088/2515-7639/ad3aa3","url":null,"abstract":"Inorganic phosphosulfides—materials containing phosphorus, sulfur, and at least one metal—are a vast and chemically-versatile family of materials. Benefiting from a wide range of possible phosphorus oxidation states, phosphosulfide semiconductors exist as thiophosphate compounds with various types of P–S polyanions, as genuine multi-anion compounds with or without P–P bonds, as solid solutions, and as many intermediate cases. Since metal phosphides and metal sulfides are among the highest-performing optoelectronic semiconductors, it seems reasonable to consider the phosphosulfide family as a potential pool of materials for solar cells, photoelectrochemical cells, and light-emitting diodes. Nevertheless, phosphosulfide semiconductors have very rarely been characterized with these applications in mind. In this perspective article, we reflect on the potential applicability of known and hypothetical phosphosulfides as light absorbers and emitters in optoelectronic devices. First, we distill the existing knowledge accessible through the Materials Project database, finding promising phosphosulfides among the compounds already present in the database and identifying what we see as the general advantages and challenges of phosphosulfides as optoelectronic materials. Then, we propose three concrete research directions aimed at finding novel high-quality phosphosulfide semiconductors with high light absorption coefficients, high carrier mobilities, and long carrier lifetimes. In particular, we argue that the versatility of phosphorus in this class of materials could potentially be exploited to engineer defect tolerance. Finally, we describe and explain the advantages of a custom synthesis setup dedicated to high-throughput exploration of thin-film phosphosulfides.","PeriodicalId":501825,"journal":{"name":"Journal of Physics: Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140612854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Graph Representation of Multi-dimensional Materials 多维材料的图形表示法

Journal of Physics: Materials Pub Date : 2024-04-11 DOI: 10.1088/2515-7639/ad3d89

Tong Cai, Amanda J Parker, Amanda S. Barnard

引用次数: 0

Indirect control of band gaps by manipulating local atomic environments using solid solutions and co-doping 利用固溶体和共掺杂操纵局部原子环境，间接控制带隙

Journal of Physics: Materials Pub Date : 2024-04-09 DOI: 10.1088/2515-7639/ad3c92

M. Al-Farsi, Michele Cutini, Neil Allan, Judy N Hart

{"title":"Indirect control of band gaps by manipulating local atomic environments using solid solutions and co-doping","authors":"M. Al-Farsi, Michele Cutini, Neil Allan, Judy N Hart","doi":"10.1088/2515-7639/ad3c92","DOIUrl":"https://doi.org/10.1088/2515-7639/ad3c92","url":null,"abstract":"\u0000 The ability to tune band gaps of semiconductors is important for many optoelectronics applications including photocatalysis. A common approach to this is doping, but this often has the disadvantage of introducing defect states in the electronic structure that can result in poor charge mobility and increased recombination losses. In this work, density functional theory calculations are used to understand how co-doping and solid solution formation can allow tuning of semiconductor band gaps through indirect effects. The addition of ZnS to GaP alters the local atomic environments of the Ga and P atoms, resulting in shifts in the energies of the Ga and P states that form the valence and conduction band edges, and hence changes the band gap without altering which atoms form the band edges, providing an explanation for previous experimental observations. Similarly, N doping of ZnO is known from previous experimental work to reduce the band gap and increase visible-light absorption; here we show that, when co-doped with Al, the Al changes the local environment of the N atoms, providing further control of the band gap without introducing new states within the band gap or at the band edges, while also providing an energetically more favourable state than N-doped ZnO. Replacing Al with elements of different electronegativity is an additional tool for band gap tuning, since the different electronegativities correspond to different effects on the N local environment. The consistency in the parameters identified here that control the band gaps across the various systems studied indicates some general concepts that can be applied in tuning the band gaps of semiconductors, without or only minimally affecting charge mobility.","PeriodicalId":501825,"journal":{"name":"Journal of Physics: Materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140720632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0