Publications

The plane-wave density functional theory code CASTEP was used with the Tkatchenko-Scheffler van der Waals correction scheme and the generalized gradient approximation of Perdew, Burke, and Ernzerhof (GGA PBE) to calculate the binding energy of Au, Cr, and Al atoms on the armchair and zigzag edge binding sites of monolayer graphene, and at the high-symmetry adsorption sites of single layer, bilayer, and trilayer graphene. All edge site binding energies were found to be substantially higher than the adsorption energies for all metals. The adatom migration activation barriers for the lowest energy migration paths on pristine monolayer, bilayer, and trilayer graphene were then calculated and found to be smaller than or within an order of magnitude of ${k}_{B}T$ at room temperature, implying very high mobility for all adatoms studied. This suggests that metal atoms evaporated onto graphene samples quickly migrate across the lattice and bind to the energetically favorable edge sites before being characterized in the microscope. We then prove this notion for Al and Au on graphene with scanning transmission electron microscopy (STEM) images showing that these atoms are observed exclusively at edge sites, and also hydrocarbon-contaminated regions, where the pristine regions of the lattice are completely devoid of adatoms. Additionally, we review the issue of fixing selected atomic positions during geometry optimization calculations for graphene/adatom systems and suggest a guiding principle for future studies.

We show that graphene deposited on a substrate has a non-negligible density of atomic scale defects. This is evidenced by a previously unnoticed D peak in the Raman spectra with intensity of about 1% with respect to the G peak. We evaluated the effect of such impurities on electron transport by mimicking them with hydrogen adsorbates and measuring the induced changes in both mobility and Raman intensity. If the intervalley scatterers responsible for the D peak are monovalent, their concentration is sufficient to account for the limited mobilities achievable in graphene on a substrate.

Abstract A strategy is reported for fabricating 3D‐printed electrodes using self‐assembled graphene oxide (GO) core–shell microspheres as tunable microreactors. This approach enables control over microsphere size and shell thickness via pH adjustment and sonication parameters, yielding either individual conductive particles or interconnected networks suitable for Direct Ink Writing. Following pyrolysis, the resulting hierarchically porous, rigid constructs exhibit surface area of 1000 m 2 g −1 and compressive strengths up to 9.5 MPa – outperforming most 3D‐printed carbon supercapacitor structures in mechanical robustness. Electrochemically, the optimized architecture delivers 125 F g −1 , 1.4 F and 4.7 F cm −3 in 1 m H 2 SO 4 , and maintains >95% of its capacity after 30 000 cycles while preserving structural integrity. This method combines bottom‐up GO self‐assembly with top‐down additive manufacturing to produce mechanically resilient, high‐performance supercapacitor electrodes – bridging nanoscale material design with macroscale energy storage systems engineering.

The development of multifunctional composite phase change materials has emerged as a popular research field to achieve efficient thermal energy storage and management across diverse application scenarios. Herein, a novel flexible reversible thermochromic phase change film (TC-PCMs/nBN/OBC) has been proposed. The film comprises a thermochromic compound, hexagonal boron nitride (h-BN), and olefin block copolymers (OBC), and features a layered structure with h-BN embedded laterally in OBC. This design enhances thermal conductivity and confers reversible thermochromic ability, as well as excellent flexibility. The TC-PCMs/nBN/OBC film can perform multiple functions, including thermal storage, light-to-thermal conversion, and temperature-controlled information storage. Additionally, a sandwich-like structure of the multifunctional smart flexible device (TC-PCMs/10BN/OBC-CC) is fabricated using TC-PCMs/10BN/OBC and conductive cloth via easy layer-by-layer assembly. This flexible device is simple to prepare, retains the excellent comprehensive properties of TC-PCMs/nBN/OBC. Moreover, the presence of conductive cloth enabled this device to achieve good electric-to-thermal conversion efficiency (86.5 %). Overall, the results demonstrate that TC-PCMs/10BN/OBC can meet diverse application requirements.

Reduced graphene oxide (rGO) has attracted interest in its potential application in large area photodetectors owing to its ease of manufacture and wideband optical absorbance. Here, we report that thin rGO films produced via vacuum filtration of GO followed by reduction by immersion in L-ascorbic acid are capable of sensing light through a bolometric mechanism. The photoresponse of these rGO thin films can be further enhanced by dropcasting graphene quantum dots (GQDs) on the rGO surface. These GQDs were observed to increase the opacity of the rGO film and hence its absorptivity of light, thereby enabling a significant increase in the photoresponse of the device.

Hexagonal boron nitride (hBN) is a large band gap layered crystal, frequently incorporated in van der Waals (vdW) heterostructures as an insulating or tunnel barrier. Localised states with energies within its band gap can emit visible light, relevant to applications in nanophotonics and quantum information processing. However, they also give rise to conducting channels, which can induce electrical breakdown when a large voltage is applied. Here we use gated tunnel transistors to study resonant electron tunnelling through the localised states in few atomic-layer hBN barriers sandwiched between two monolayer graphene electrodes. The measurements are used to determine the energy, linewidth, tunnelling transmission probability, and depth within the barrier of more than 50 distinct localised states. A three-step process of electron percolation through two spatially separated localised states is also investigated.

ADVERTISEMENT RETURN TO ISSUEPREVAddition/CorrectionNEXTORIGINAL ARTICLEThis notice is a correctionCorrection to Tuning the Pseudospin Polarization of Graphene by a Pseudomagnetic FieldAlexander GeorgiAlexander GeorgiMore by Alexander Georgi, Peter Nemes-InczePeter Nemes-InczeMore by Peter Nemes-Inczehttp://orcid.org/0000-0002-1222-3020, Ramon Carrillo-BastosRamon Carrillo-BastosMore by Ramon Carrillo-Bastos, Daiara FariaDaiara FariaMore by Daiara Faria, Silvia Viola KusminskiySilvia Viola KusminskiyMore by Silvia Viola Kusminskiy, Dawei ZhaiDawei ZhaiMore by Dawei Zhai, Martin SchneiderMartin SchneiderMore by Martin Schneider, Dinesh SubramaniamDinesh SubramaniamMore by Dinesh Subramaniam, Torge MashoffTorge MashoffMore by Torge Mashoff, Nils M. FreitagNils M. FreitagMore by Nils M. Freitaghttp://orcid.org/0000-0002-5043-6385, Marcus LiebmannMarcus LiebmannMore by Marcus Liebmann, Marco PratzerMarco PratzerMore by Marco Pratzer, Ludger WirtzLudger WirtzMore by Ludger Wirtz, Colin R. WoodsColin R. WoodsMore by Colin R. Woods, Roman V. GorbachevRoman V. GorbachevMore by Roman V. Gorbachev, Yang CaoYang CaoMore by Yang Cao, Kostya S. NovoselovKostya S. NovoselovMore by Kostya S. Novoselov, Nancy SandlerNancy SandlerMore by Nancy Sandlerhttp://orcid.org/0000-0001-7288-6339, and Markus Morgenstern*Markus MorgensternMore by Markus MorgensternCite this: Nano Lett. 2018, 18, 10, 6654Publication Date (Web):September 28, 2018Publication History Published online28 September 2018Published inissue 10 October 2018https://pubs.acs.org/doi/10.1021/acs.nanolett.8b03872https://doi.org/10.1021/acs.nanolett.8b03872correctionACS PublicationsCopyright © 2018 American Chemical Society. This publication is available under these Terms of Use. Request reuse permissions This publication is free to access through this site. Learn MoreArticle Views1226Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail PDF (223 KB) Get e-Alertsclose Get e-Alerts

Control over the electronic spectrum at low energy is at the heart of the functioning of modern advanced electronics: high electron mobility transistors, semiconductor and Capasso terahertz lasers, and many others. Most of those devices rely on the meticulous engineering of the size quantization of electrons in quantum wells. This avenue, however, hasn't been explored in the case of 2D materials. Here we transfer this concept onto the van der Waals heterostructures which utilize few-layers films of InSe as quantum wells. The precise control over the energy of the subbands and their uniformity guarantees extremely high quality of the electronic transport in such systems. Using novel tunnelling and light emitting devices, for the first time we reveal the full subbands structure by studying resonance features in the tunnelling current, photoabsorption and light emission. In the future, these systems will allow development of elementary blocks for atomically thin infrared and THz light sources based on intersubband optical transitions in few-layer films of van der Waals materials.

Relevance . In accordance with the guidelines on the clinical investigation of clotting factor VIII products of the European Medicines Agency and guidelines on pharmacovigilance of the Eurasian Economic Union, after registration of a new drug, it is recommended to study its efficacy and safety on a large population of patients in a standard medical practice to clarify and identify new data. Materials and methods . In a prospective, multicenter, open-label, uncontrolled observational study, the efficacy and safety of the domestic recombinant B-domain deleted blood clotting factor FVIII (FVIII) (moroctocog alfa, Octofactor®, JSC “GENERIUM”) in patients with moderate and severe hemophilia A in the context of standard medical practice (study protocol number CI-51/15). Patients received the drug in terms of standard medical practice for the purpose of prophylactic treatment or on demand treatment. For prophylactic treatment Octofactor was administered to patients according to the instructions for medical use in a single dose of 20–40 IU/kg every 2–3 days. In the case of bleeding a single dose of Octofactor was calculated taking into account the severity and localization of bleeding in accordance with the instructions for medical use. The results of the treatment were analyzed for a period of 52 ± 2 weeks. The main parameter for evaluating the efficacy was the frequency of spontaneous bleeding that occurred within 48–72 hours after the administration of the Octofactor. Additional parameters for evaluating the efficacy included: the severity of spontaneous bleeding arising during the prophylactic treatment; the number of injections and the total dose of the Octofactor to stop 1 episode of bleeding; the amount of Octofactor used during the entire observation period (52 ± 2 weeks) and for 1 month both for prophylaxis and for stopping the bleeding that occurred; an indicator of the efficacy of therapy on the scale for determining the response to treatment of acute hemarthrosis (World Federation of Hemophilia, WFH). Results. According to the results of the screening survey 237 male patients aged from 19 to 78 years old (mean age 35.2 ± 11.1 years) with moderate and severe hemophilia A (FAS-population) were included in the study. The efficacy of therapy was evaluated in 202 patients who underwent all the planned procedures during the observation period (PP-population). 193 (95.5 %) patients received prophylactic treatment, 9 (4.5 %) patients received on-demand treatment. Evaluation of the efficacy of treatment was carried out on the basis of basic and additional parameters. The main parameter for evaluating the efficacy – the frequency of spontaneous bleeding that occurred within 48–72 hours after the administration of the Octofactor – was 52 ± 2 weeks within 1.4 ± 2.9 cases. At the same time, the proportion of spontaneous bleeding that occurred within 48–72 hours after administration of the Octofactor preparation was 45.2 % of the total number of spontaneous bleeding and 15.6 % of the total number of all bleeding in patients who received prophylactic treatment. Among 608 spontaneous bleeding that occurred in patients receiving prophylactic treatment, 287 (47.2 %) of the bleeding were mild, 289 (47.5 %) were moderate and 32 (5.3 %) were heavy. Of the 275 spontaneous bleeding that occurred within 48–72 hours after administration of the study drug for prophylactic purposes, 117 (42.5 %) episodes were mild, 146 (53.1 %) were moderate, and 12 (4.4 %) were severe. With prophylactic administration the average single dose of the Octofactor was 2036.3 ± 884.7 IU, or 27.3 ± 11.2 IU/kg, in the treatment of bleeding occured during prophylactic treatment – 2227.7 ± 1087 IU, in the treatment of bleeding in patients receiving the drug only on demand – 2280.7 ± 1037.2 IU. The average monthly intake of the drug by one patient in prophylactic treatment was 19.75 ± 9.75 thousand IU, while the average monthly consumption of the drug for preventing bleeding from one patient was 17.16 ± 9.13 thousand IU for stopping bleeding against the background prevention – 3.87 ± 3.97 thousand IU. One patient who received on-demand treatment had an average monthly average of 13.47 ± 13.46 thousand IU of the Octofactor preparation. For stopping 1 bleeding, on average, 1.7 ± 1.7 injections of the Octofactor preparation were required, in the prophylactic treatment group – 1.8 ± 1.8, and in the on-demand treatment group – 1.5 ± 1.1. In the overwhelming majority of cases, patients of both groups showed excellent and good response to all treatment of acute hemarthrosis on the scale of the WFH on all visits, the reaction was moderate in a few episodes, and only in 1 case of acute hemarthrosis there was no response to the drug administration. The safety of therapy was evaluated in 228 patients who received at least 1 Octofactor administration during the study (mITT-population). There were 66 adverse events in 40 patients, 10 of them were associated with the use of the drug, the most significant of which were the formation of inhibiting antibodies to FVIII in low titer (1.5 U) in 1 patient and the development of allergic reactions in 2 patients. Conclusions. Under the conditions of standard medical practice the efficacy and safety of Octofactor was confirmed for both prophylactic treatment and on-demand bleeding treatment in adult patients with severe and moderate hemophilia A.

No abstract is provided for this article.

We present a systematic experimental and theoretical study of the two-phonon (2D) Raman scattering in graphene under uniaxial tension. The external perturbation unveils that the 2D mode excited with 785 nm has a complex line-shape mainly due to the contribution of two distinct double resonance scattering processes (inner and outer) in the Raman signal. The splitting depends on the direction of the applied strain and the polarization of the incident light. The results give new insight into the nature of the 2D band and have significant implications for the use of graphene as reinforcement in composites since the 2D mode is crucial to assess how effectively graphene uptakes an applied stress or strain.

Coherent manipulation of binary degrees of freedom is at the heart of modern quantum technologies. Graphene, the first atomically thin 2D material, offers two binary degrees: the electron spin and the valley degree of freedom. Efficient spin control has been demonstrated in many solid state systems, while exploitation of the valley has only recently been started without control for single electrons. Here, we show that van-der Waals stacking of 2D materials offers a natural platform for valley control due to the relatively strong and spatially varying atomic interaction between adjacent layers. We use an edge-free quantum dot, induced by the tip of a scanning tunneling microscope into graphene on hBN. We demonstrate a valley splitting, which is tunable from -5 meV to +10 meV (including valley inversion) by sub-10-nm displacements of the quantum dot position. This boosts controlled valley splitting of single electrons by more than an order of magnitude, which will probably enable robust spin qubits and valley qubits in graphene.

Most AI-for-Materials research to date has focused on ideal crystals, whereas real-world materials inevitably contain defects that play a critical role in modern functional technologies. The defects break geometric symmetry and increase interaction complexity, posing particular challenges for traditional ML models. Here, we introduce Defect-Informed Equivariant Graph Neural Network (DefiNet), a model specifically designed to accurately capture defect-related interactions and geometric configurations in point-defect structures. DefiNet achieves near-DFT-level structural predictions in milliseconds using a single GPU. To validate its accuracy, we perform DFT relaxations using DefiNet-predicted structures as initial configurations and measure the residual ionic steps. For most defect structures, regardless of defect complexity or system size, only 3 ionic steps are required to reach the DFT-level ground state. Finally, comparisons with scanning transmission electron microscopy (STEM) images confirm DefiNet's scalability and extrapolation beyond point defects, positioning it as a valuable tool for defect-focused materials research.