Article
Multidisciplinary Sciences
Dominique Laniel, Florian Trybel, Bjoern Winkler, Florian Knoop, Timofey Fedotenko, Saiana Khandarkhaeva, Alena Aslandukova, Thomas Meier, Stella Chariton, Konstantin Glazyrin, Victor Milman, Vitali Prakapenka, Igor A. Abrikosov, Leonid Dubrovinsky, Natalia Dubrovinskaia
Summary: This study presents the chemical and structural diversity of lanthanum hydrides synthesized under high pressure, providing clues for the search of other hydrides and high-temperature superconductors. However, assessing potentially superconducting phases and the nature of electronic transitions remains a challenge.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Zheng Zhou, Yikun Zhu, Zheng Wei, John Bergner, Christian Neiss, Susanne Doloczki, Andreas Goerling, Milan Kivala, Marina A. Petrukhina
Summary: The study found that the chemical reduction of octaphenyltetrabenzocyclooctatetraene framework can readily produce the corresponding tetra-anion instead of the expected aromatic dianion. X-ray crystallography shows that the highly contorted tetra-anion is stabilized by the coordination of two internally bound Li+ ions, while two external cations are solvent separated. Density-functional theory calculations suggest that the formation of the highly charged tetra-reduced carbanion is stabilized through Li+ coordination under the applied experimental conditions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Physics, Multidisciplinary
Liang Ma, Kui Wang, Yu Xie, Xin Yang, Yingying Wang, Mi Zhou, Hanyu Liu, Xiaohui Yu, Yongsheng Zhao, Hongbo Wang, Guangtao Liu, Yanming Ma
Summary: The discovery of superconductive rare earth and actinide superhydrides has opened up a new era of high-pressure superconductivity research. The successful synthesis of CaH6 and its remarkable superconducting properties highlight the potential for further exploration and development of high-temperature superconducting materials.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Vladimir Ya. Lee, Ryo Sakai, Kazunori Takanashi, Olga A. Gapurenko, Ruslan M. Minyaev, Heinz Gornitzka, Akira Sekiguchi
Summary: Two novel 18-electron titanium germylene complexes with distinct structural characteristics were synthesized and classified as different types of complexes, providing important insights into the chemical bonding between germanium and titanium.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Yin L. Xu, Yang M. Chen, Xiao Z. Yan, Yi B. Huang, Xing Z. Zhou, Quan X. Wu, Xiao W. Sheng, Fang G. Kuang
Summary: In this study, the crystal structures and physical properties of an H-S-La system were systematically investigated using first-principles calculations combined with the CALYPSO structure exploration technique. Four stable stoichiometries were predicted, and the superconducting transition temperatures of these compounds were calculated.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Prashant Singh, Tyler Del Rose, Yaroslav Mudryk
Summary: The thermodynamic stability of disordered rare-earth phases SmX2 and Sm10X21 (X = Ni, Pd) was investigated using machine-learning based analytical descriptor and first-principles density functional theory methods. The contrasting phase stability between Ni and Pd compounds in the cubic Laves phase was explored through thermodynamic convex hull analysis and electronic-structure analysis. The study highlights the importance of ab-initio methods and computationally inexpensive analytical descriptors in analyzing the thermodynamic and electronic properties of rare-earth compounds.
Article
Chemistry, Multidisciplinary
Guangrui Zhang, Hongbo Hao, Yuping Liang, Yu Qiao, Songwei Bai, Heyan Liu, Hongzhi Luo
Summary: The equiatomic quaternary Heusler alloy FeRuCrSi was synthesized and its atomic ordering, magnetic properties and electronic structure were investigated. The alloy exhibited a single phase with a lattice constant of 5.811 Å at room temperature. A disorder related to the random occupation of Fe and Ru at specific sites was identified. The disorder affected the magnetic properties and narrowed the gaps in the electronic structure.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2023)
Article
Chemistry, Multidisciplinary
Timo Fuchs, Valentin Briega-Martos, Jakub Drnec, Natalie Stubb, Isaac Martens, Federico Calle-Vallejo, David A. Harrington, Serhiy Cherevko, Olaf M. Magnussen
Summary: The degradation of Pt-containing oxygen reduction catalysts for fuel cell applications is studied using operando high-energy surface X-ray diffraction, online mass spectrometry, and density functional theory. It is found that anodic dissolution, detected during oxidation, and cathodic dissolution, observed during reduction, are linked to two different oxide phases. The amount of surface restructuring after an oxidation/reduction cycle is potential-independent after the saturation coverage of the first oxide phase.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
S. Swathilakshmi, Reshma Devi, Gopalakrishnan Sai Gautam
Summary: In this study, we evaluated the accuracy and computational efficiency of the recently developed metaGGA functional r(2)SCAN in transition metal oxide systems and compared it with SCAN. We assessed various properties of binary 3d TMOs calculated by r(2)SCAN, including oxidation enthalpies, lattice parameters, magnetic moments, and band gaps, and compared them with SCAN calculations and experimental values. Our results showed that including the U-correction with r(2)SCAN improved the description of TMOs' ground state properties with better computational efficiency than SCAN. The overall computational time required for r(2)SCAN(+U) was lower than SCAN(+U).
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Chemistry, Multidisciplinary
Hayato Moriyama, Kazuya Otsubo, Kunihisa Sugimoto, Shogo Kawaguchi, Hiroshi Kitagawa
Summary: This paper presents a new one-dimensional halogen-bridged dinuclear-metal complex with a bulky pendant ligand. The strain caused by the bulky ligand leads to the achievement of a pure alternate charge-polarization state. This study is significant for designing low-dimensional materials to achieve new electron-lattice coupled electronic states.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Simon R. Larsen, Daniel Hedlund, Rebecca Clulow, Martin Sahlberg, Peter Svedlindh, Erna K. Delczeg-Czirjak, Johan Cedervall
Summary: The magnetic properties of the (Mn,Co)(23)B-6 compound were investigated using synchrotron X-ray diffraction, neutron powder diffraction, magnetometry, and electronic structure calculations. The study revealed mixed metal occupancies in the compound and a ferrimagnetic structure.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Multidisciplinary Sciences
Wuhao Chen, Xiaoli Huang, Dmitrii V. Semenok, Su Chen, Di Zhou, Kexin Zhang, Artem R. Oganov, Tian Cui
Summary: This study successfully synthesized hcp-(La,Ce)H9-10 at 113GPa and observed high-temperature superconductivity at 176K and 100GPa, with an extrapolated upper critical field of 235T. The superconducting properties of La-Ce-H were significantly enhanced compared to the binary La-H and Ce-H compounds, indicating the potential of solid solution for improving superconductors.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Leonid P. Salamakha, Oksana Sologub, Berthold Stoeger, Herwig Michor, Peter F. Rogl, Ernst Bauer
Summary: The existence of a boron-filled fl-Mn-type compound has been observed for the first time in the Pd-Cu-B system. The crystal structure, homogeneity field, and phase equilibria of this compound have been studied using various analytical methods. It has been found that the B-filled fl-Mn-type structure exists within a certain compositional range with specific boron population. The metallic behavior and electronic structure of this compound have also been examined.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Multidisciplinary
Gavin Sampson, Nicholas C. Bristowe, Sam T. Carr, Asad Saib, Gavin B. G. Stenning, Ewan R. Clark, Paul J. Saines
Summary: This work describes a homometallic spin-1/2 tetrabromocuprate adopting a bilayer structure. Magnetic-susceptibility measurements show a broad maximum centred near 70 K, indicating strong antiferromagnetic coupling between neighbouring copper atoms in different layers of the bilayer. Weak intralayer ferromagnetic interactions between copper cations in neighbouring dimers also exist. First-principles calculations confirm these observations and suggest the presence of a spin ladder within the bilayer with antiferromagnetic rung and weaker ferromagnetic rail couplings.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Physical
S. Kazim, D. Mastrippolito, P. Moras, M. Jugovac, T. Klimczuk, M. Ali, L. Ottaviano, R. Gunnella
Summary: We investigated the challenging CrCl3 surface using photon energy dependent photoemission (PE). By studying the core and valence electrons of cleaved single crystals in either ultra-high vacuum (UHV) or air, we confirmed the atomic composition with respect to the expected bulk atomic structure. The presence of a stable, but only partially ordered Cl-O-Cr surface was revealed by a common spectroscopic denominator. Through analysis of multiplet components, we quantified the electron charge transfer and the reduced crystal field due to the established polarization field. The methodology used in this study can have a significant impact on determining the structure of ordered sub-oxide phases in mono or bi-layer Cr trihalides.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Takato Hotta, Akihiko Ueda, Shohei Higuchi, Mitsuhiro Okada, Tetsuo Shimizu, Toshitaka Kubo, Keiji Ueno, Takashi Taniguchi, Kenji Watanabe, Ryo Kitaura
Summary: The van der Waals heterostructures prepared using the graphene-capping-assisted AFM nano-squeezing method have an ultratlat structure and high quality, avoiding the appearance of random electrostatic potential and trion peaks.
Article
Chemistry, Multidisciplinary
Ioanna K. Sideri, Youngwoo Jang, Jose Garces-Garces, Angela Sastre-Santos, Ruben Canton-Vitoria, Ryo Kitaura, Fernando Fernandez-Lazaro, Francis D'Souza, Nikos Tagmatarchis
Summary: The study reports the covalent functionalization of MoS2 with PDI, revealing interesting electron and energy characteristics of the newly prepared MoS2-PDI hybrid material through detailed characterization.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Physics, Applied
Kaoru Hisama, Yanlin Gao, Mina Maruyama, Ryo Kitaura, Susumu Okada
Summary: The study shows that the Fermi level of Nb-doped WSe2 can be tuned by an external electric field, thus controlling its electronic structure. Regardless of Nb concentration and arrangement, the electric field simply shifts the Fermi level, resulting in a constant quantum capacitance under all conditions.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Sihan Zhao, Ryo Kitaura, Pilkyung Moon, Mikito Koshino, Feng Wang
Summary: This review summarizes experimental observations and theoretical perspectives related to interlayer interactions in 1D vdW moire superlattices, focusing on the unique optical features and physics in 1D DWNTs arising from the non-trivial strong interlayer coupling effect. Proposed and discussed are future directions and questions in probing the intriguing physical phenomena in 1D vdW moire superlattices, including correlated physics in different 1D moire systems beyond DWNTs.
Article
Nanoscience & Nanotechnology
Yuki Matsunaga, Jun Hirotani, Haruka Omachi
Summary: By using HATCN as a dopant, CNT-TFTs exhibit good p-type characteristics even in high-temperature environments, and stable performance under ambient conditions can be achieved through surface encapsulation.
Article
Chemistry, Multidisciplinary
Emi Saita, Masaki Iwata, Yuki Shibata, Yuki Matsunaga, Rie Suizu, Kunio Awaga, Jun Hirotani, Haruka Omachi
Summary: This study successfully describes the concise exfoliation of multilayer Ti3C2Tx MXene containing residual aluminum atoms. The exfoliated single-layer Ti3C2Tx MXenes were proved to have excellent macroscale electric conductivity, and a flexible transparent conductive film was formed using the exfoliated dispersion and demonstrated in an electrical application.
FRONTIERS IN CHEMISTRY
(2022)
Article
Nanoscience & Nanotechnology
Shota Nakahara, Takahiro Morita, Haruka Omachi, Masafumi Inaba, Michihiko Nakano, Junya Suehiro
Summary: Carbon nanotubes (CNTs) are promising gas sensing materials due to their large specific area and high sensitivity to charge differentiation. By modulating the CNT channel potential and the Schottky barrier height, gas detection can be achieved. The experimental results show that the modulation rate of the Schottky barrier in carbon nanotubes is higher than that of the channel potential shift.
Article
Chemistry, Physical
Ruben Canton-Vitoria, Takato Hotta, Yuri Tanuma, Ioanna K. Sideri, Nikos Tagmatarchis, Chris Ewels, Ryo Kitaura
Summary: We successfully functionalized MoS2 and WS2 with Zn-porphyrin through 1,2-dithiolane addition, creating mixed 0-2 dimensional materials. The localization of porphyrins on the basal plane of TMDs resulted in a new emission band in the NIR region, originating from charge-separated states. The optical response of excitonic species was enhanced, and sensing time-response improved after functionalization, while the stability of WS2 and MoS2 against atmospheric photodegradation was also enhanced.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Ruben Canton-Vitoria, Takato Hotta, Mengsong Xue, Shaochun Zhang, Ryo Kitaura
Summary: In this study, a straightforward method has been developed to obtain nanoribbons with controllable widths and lengths by O2 etching of the metallic phase in metallic/semiconducting in-plane heterostructures of monolayer MoS2. The nanoribbons also showed excellent field-effect transistor performance and were used as a template to build heterostructures with other transition metal dichalcogenides. This study offers a simple production method for nanoribbons with wide applications in nanotechnology and chemistry.
Article
Chemistry, Physical
Yuika Saito, Takahiro Kondo, Sora Harada, Ryo Kitaura, Maria Vanessa Balois-Oguchi, Norihiko Hayazawa
Summary: In this study, we used polarization resonance Raman microscopy to investigate the interactions between single-walled carbon nanotubes (SWCNTs) and encapsulated molecules. We focused on C-70 encapsulated in SWCNTs and examined the Raman spectral pattern under different laser polarizations and excitation wavelengths. Our results showed that the resonance Raman process was modulated by a charge transfer contribution between C-70 and SWCNTs, which depended on the incident polarization and excitation wavelength. The intensity of the local electronic field inside a SWCNT was higher for parallel excitation than perpendicular excitation when the nanotubes were bundled.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Multidisciplinary
Shaochun Zhang, Mina Maruyama, Susumu Okada, Mengsong Xue, Kenji Watanabe, Takashi Taniguchi, Kazuki Hashimoto, Yasumitsu Miyata, Ruben Canton-Vitoria, Ryo Kitaura
Summary: This study reports the observation of the photovoltaic effect in a WS2/MoS2 van der Waals heterostructure. Light excitation of WS2/MoS2 at a wavelength of 633 nm leads to a photocurrent without applying bias voltages.
Article
Chemistry, Multidisciplinary
Ruben Canton-Vitoria, Kotaro Sato, Yashiro Motooka, Shinya Toyokuni, Zheng Liu, Ryo Kitaura
Summary: We made sensors by modifying MoS2 and WS2 surfaces with COVID-19 antibodies and examined their stability, reusability, sensitivity, and selectivity. Antibodies interact strongly with Mo or W sites, resulting in durable devices that remain stable for several days in air or water. The antibodies remain intact even during aggressive cleaning at pH 3, allowing reuse without significant loss of sensitivity. The nanodevice can be used for different patient samples, with a limit of detection of 1 fg ml(-1) at room temperature and a response time of 1 second, showing selectivity against interferences.
Article
Materials Science, Multidisciplinary
Kensuke Saito, Mitsuhiro Okada, Ryo Kitaura, Hideo Kishida, Takeshi Koyama
Summary: This study examines the exciton diffusion in the MoS2 monolayer on a femtosecond timescale, revealing important insights for its application in light-emitting devices. The photoluminescence decay of A and B excitons was observed, with analysis showing trapping at deactivation centers through diffusion. The determination of diffusion coefficient and exciton mobility further contributes to the understanding of two-dimensional exciton diffusion in MoS2.
Article
Chemistry, Multidisciplinary
Anastasios Stergiou, Christina Stangel, Ruben Canton-Vitoria, Ryo Kitaura, Nikos Tagmatarchis
Summary: This study describes the functionalization of chemically exfoliated molybdenum disulfide nanosheets with a benzo-15-crown-5 ether for the fabrication of an ion-responsive electrode. Various characterization techniques revealed the structural characteristics and performance of the material, demonstrating the crucial role of basal plane functionalization in stabilizing the 1T phase.
Article
Physics, Applied
Yuki Matsunaga, Jun Hirotani, Yutaka Ohno, Haruka Omachi
Summary: The gel column chromatographic separation technique using cost-efficient polysaccharide isomaltodextrin (IMD) as a replacement for expensive dextran-based gels has proven effective in achieving high-purity separation of s-SWCNTs. The cross-linking reaction under precisely controlled basic conditions resulted in sub-micrometer porous IMD gels, crucial for successful gel chromatographic SWCNT separation. Thin-film transistors prepared from the separated s-SWCNTs exhibited excellent on/off ratios.
APPLIED PHYSICS EXPRESS
(2021)
