Article
Engineering, Environmental
Xiao-Qi Li, Song Jiang, Lili Zhang, Meng-Ke Zou, Yang Jian, Dong-Ming Sun, Peng-Xiang Hou, Hui -Ming Cheng, Chang Liu
Summary: This study reports a new method for synthesizing isolated s-SWCNTs using an oxygen-assisted floating catalyst chemical vapor deposition method. By controlling the density of nucleated SWCNTs, efficient selective etching of metallic-SWCNTs was achieved. Additionally, oxygen was found to limit the size of catalyst nanoparticles, resulting in isolated s-SWCNTs with a narrow diameter distribution.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Materials Science, Multidisciplinary
Junhui Xiao, Kai Zou, Tao Chen, Yang Peng, Wei Ding, Jinhua Chen, Bing Deng, Hong Li, Zhen Wang
Summary: In this study, a magnetic separation-shaking table gravity separation process was successfully used to extract Sc from V-Ti magnetite tailings, with Sc enrichment achieved through chloridizing roasting and hydrochloric acid leaching. The majority of the Sc was dissolved as Sc3+ in the liquid phase, indicating efficient extraction of Sc from the roasted ores.
Article
Chemistry, Physical
Christopher M. Sims, Jeffrey A. Fagan
Summary: This research quantitatively determined the effects of surfactant chemistry and polymer chain length on the extraction of specific single-wall carbon nanotube (SWCNT) species in an aqueous two-polymer phase extraction (ATPE) separation. The results showed that alkyl surfactant tail length strongly affects the amount of surfactant necessary for extraction in ATPE. Substitution of different bile salts results in different surfactant packings on the SWCNTs, significantly affecting the concentrations required for extraction.
Article
Chemistry, Multidisciplinary
Liang Xu, Michal Valasek, Frank Hennrich, Elaheh Sedghamiz, Montserrat Penaloza-Amion, Daniel Haussinger, Wolfgang Wenzel, Manfred M. Kappes, Marcel Mayor
Summary: The study proposes a novel method for separating semiconductor SWCNTs from polymers using acid treatment, which allows for the re-synthesis of chiral polymers with defined chirality. This approach enables efficient separation of nanotube handedness.
Article
Materials Science, Multidisciplinary
Song Li, Zhaohui Jin, Xiaoguo Gong, Hua Huang, Shaokang Guan, Guangyin Yuan
Summary: Mg-Sc alloys with less than 25 atomic percent Sc exhibit shape memory effects, and the martensitic transformation temperature can be elevated by tuning the chemical ordering and microstructure of Mg-Sc precipitates. Increased ground-state energy difference and decreased vibra-tional free energy difference between austenite and martensite contribute mainly to the stabilized phase transformations.
Article
Crystallography
Jiajun Liao, Zhengwang Cheng, Xinguo Ma, Fengda Wan, Wangyang Duan, Yuehuan Cheng, Mei Wang
Summary: The piezoelectric properties of Sc-or Er-doped wurtzite AlN at different dopant concentrations were investigated using first-principles calculations. It was found that Sc0.5Al0.5N and Er0.5Al0.5N exhibited the highest piezoelectric constants at a dopant concentration of 0.5, with values of 25.50 pC/N and 9.34 pC/N, respectively. The enhancement of piezoelectric constant was attributed to the long polarization length and improved ionicity of Al-N bond after doping.
JOURNAL OF CRYSTAL GROWTH
(2022)
Article
Chemistry, Multidisciplinary
Svetlana I. Serebrennikova, Daria S. Kopylova, Yuriy G. Gladush, Dmitry V. Krasnikov, Sakellaris Mailis, Albert G. Nasibulin
Summary: Phototransistors utilizing sparse networks of SWCNTs on a silicon/silica substrate demonstrated high sensitivity and excellent performance, making them suitable for detecting extremely weak signals.
Article
Chemistry, Applied
E. Rojas-Garcia, A. A. Castaneda-Ramirez, D. Angeles-Beltran, R. Lopez-Medina, A. M. Maubert-Franco
Summary: This study successfully synthesized functionalized single-walled carbon nanotubes and HKUST-1 metal organic framework composite materials, and demonstrated that the incorporation of functionalized SWCNTs can enhance the thermal stability and hydrogen adsorption capacity of MOF, which is of great significance for hydrogen energy storage.
Article
Chemistry, Physical
Cuizhen Wang, Lingyan Zhang, Guangzhu Zhou, Jun Qiu, Yin Liu, Rongchao Yang, Jingyi Chi, Jinpu Wang
Summary: A novel reusable ion imprinted nanocomposite magnetic bentonite (IIPNMB) was synthesized for selective recovery of aqueous scandium. The IIPNMB exhibited excellent adsorption performance, fitting well with pseudo second-order kinetic model and Langmuir model. Electrostatic interaction and complexation between the amino, hydroxyl, P@O, and PAO bonds of the adsorbents and Sc(III) contributed to the high selectivity of IIPNMB. The proposed atomic structure of IIPNMB was further supported by DFT calculation, confirming the stable adsorption process and providing additional evidence for the mechanism of selective extraction.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Chemistry, Physical
Gennady L. Gutsev, Katharine M. Tibbetts, Lavrenty G. Gutsev, Bala R. Ramachandran
Summary: The ground states of neutral and anionic tetrafluoride and hexafluoride series of 3d-metal atoms from Sc to Zn were determined through a double-check approach using different methods, leading to the identification of new fluoride molecules with higher electron affinities.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Chemistry, Physical
Zhongyan Wu, Guoying Gao, Jinbo Zhang, Alexander Soldatov, Jaeyong Kim, Lin Wang, Yongjun Tian
Summary: This article systematically investigates the transport and structural properties of C-60(m-xylene) under pressure. It is found that pressure-induced dimerization of C-60 leads to a significant decrease in resistance. The temperature-dependence of resistance indicates an insulating-to-semiconducting transition accompanied with pressure-induced dimerization. The conductivity shows hysteresis during decompression, confirming different transport behaviors of the sample with retained fullerenes versus OACC.
Article
Chemistry, Applied
Junhui Xiao, Kai Zou, Nanlan Zhong, Deqiang Gao
Summary: In this study, the separation of iron and scandium from Sc-bearing red mud was investigated. The red mud contained 31.11 wt% total iron (TFe), 0.0045 wt% Sc, and hematite and ferrosilite as the main Fe-bearing minerals. By applying a novel deep reduction roasting and magnetic separation process with the addition of coke and CaO, iron was extracted and scandium was enriched from the Sc-bearing red mud. The test results showed high Fe recovery of 92.96% and Sc recovery of 98.65%.
JOURNAL OF RARE EARTHS
(2023)
Article
Materials Science, Multidisciplinary
Mohammed El Amine Monir, Zohra Bahnes, Houaria Riane, Amel Laref, Hadj Baltach
Summary: The study conducted first principle calculations on the structural, electronic structure, and magnetic properties of Ruddlesden-Popper Nd2MO4 (M = Sc and Y) compounds, revealing them to be half-metallic materials with reduced magnetic moment on Nd and small magnetic moments on nonmagnetic O1 and O2 sites.
RESULTS IN PHYSICS
(2021)
Article
Chemistry, Physical
Pablo Durand, Huiyan Zeng, Till Biskup, Vishnu Vijayakumar, Viktoriia Untilova, Celine Kiefer, Benoit Heinrich, Laurent Herrmann, Martin Brinkmann, Nicolas Leclerc
Summary: Combining side chain engineering and controlled alignment of PBTTT can produce oriented thin films with improved thermoelectric performance when doped sequentially with F(6)TCNNQ. The substitution of linear alkyl side-chains with slightly polar n-C7OC4 leads to enhanced structural order and thermo-mechanical properties. The combination of improved alignment and random orientation of intercalated F(6)TCNNQ dopants helps reach a very high charge conductivity and a record power factor in the polymer chain direction.
ADVANCED ENERGY MATERIALS
(2022)
Article
Geochemistry & Geophysics
Rita Kallio, Pekka Tanskanen, Saija Luukkanen
Summary: Scandium is classified as a critical raw material by the European Union and research is being conducted on its beneficiation from various sources. The recently discovered Kiviniemi Sc deposit in Finland has significant resources and high grade. Magnetic separation is found to be an effective method for concentrating scandium ores.
Article
Multidisciplinary Sciences
Yohei Yomogida, Kanako Horiuchi, Ryotaro Okada, Hideki Kawai, Yota Ichinose, Hiroyuki Nishidome, Kan Ueji, Natsumi Komatsu, Weilu Gao, Junichiro Kono, Kazuhiro Yanagi
Summary: The presence of hopping carriers and grain boundaries can lead to anomalous carrier types and density overestimation in Hall-effect measurements. This study systematically investigated the validity of Hall-effect results for different types of single-wall carbon nanotube films and found that while the Hall carrier types were always correct, the Hall carrier densities were overestimated by up to four orders of magnitude. This significant overestimation indicates that thin films of one-dimensional SWCNTs are quite different from conventional hopping transport systems.
SCIENTIFIC REPORTS
(2022)
Article
Nanoscience & Nanotechnology
Hiroshi Shimizu, Jiang Pu, Zheng Liu, Hong En Lim, Mina Maruyama, Yusuke Nakanishi, Shunichiro Ito, Iori Kikuchi, Takahiko Endo, Kazuhiro Yanagi, Yugo Oshima, Susumu Okada, Taishi Takenobu, Yasumitsu Miyata
Summary: This study reports the formation of a two-dimensional carrier gas in thin, ribbon-shaped bundles of WTe nanowires grown by chemical vapor deposition. The nanowires exhibit weak antilocalization and Shubnikov-de Haas oscillations at low temperatures, indicating the presence of a 2D carrier gas. The results highlight the potential of transition metal chalcogenide nanowires as building blocks for future electronic and energy-harvesting devices.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Hiroo Suzuki, Ryoki Hashimoto, Masaaki Misawa, Yijun Liu, Misaki Kishibuchi, Kentaro Ishimura, Kenji Tsuruta, Yasumitsu Miyata, Yasuhiko Hayashi
Summary: Transition metal dichalcogenides (TMDCs), including MoS2 and WS2, with their atomically thin structure and strong optoelectrical responses, show great potential as next-generation semiconducting materials for flexible optoelectronic applications. This study focuses on growing monolayer WS2 using chemical vapor deposition (CVD) technique and obtained high-quality WS2 with a narrow photoluminescence (PL) peak width. By controlling the source balance of W and S, large-sized fully monolayered WS2 and monolayer WS2 with bilayer spots were achieved. Furthermore, WS2/MoS2 lateral heterostructures were successfully created and demonstrated good electrical transport properties.
Article
Chemistry, Multidisciplinary
Mitsuhiro Okada, Jiang Pu, Yung-Chang Lin, Takahiko Endo, Naoya Okada, Wen-Hsin Chang, Anh Khoa Augustin Lu, Takeshi Nakanishi, Tetsuo Shimizu, Toshitaka Kubo, Yasumitsu Miyata, Kazu Suenaga, Taishi Takenobu, Takatoshi Yamada, Toshifumi Irisawa
Summary: The control of crystal polymorphism and exploration of metastable, two-dimensional, 1T' phase, transition-metal dichalcogenides (TMDs) have been the focus of research due to their potential applications in various fields. However, the high energy difference and phase change barrier between 1T' and 2H phases make it difficult to obtain monolayer 1T' phase TMDs. In this study, we successfully grew 1T' phase WS2 atomic layers using chemical vapor deposition (CVD) with alkali metal assistance. The resulting high-quality crystals showed superconductivity and hold promise for applications such as quantum computing and energy storage devices. The alkali metal assisted gas-source CVD growth method provides a viable approach to realizing large-scale, high-quality TMD atomic layers.
Article
Chemistry, Multidisciplinary
Naoki Wada, Jiang Pu, Yuhei Takaguchi, Wenjin Zhang, Zheng Liu, Takahiko Endo, Toshifumi Irisawa, Kazunari Matsuda, Yuhei Miyauchi, Taishi Takenobu, Yasumitsu Miyata
Summary: This study demonstrates interfacial electroluminescence in diverse TMDC monolayer in-plane heterostructures, which are grown by chemical vapor deposition and observed using electrolyte-based light-emitting devices. The WS2/WSe2 heterostructures exhibit circularly polarized electroluminescence at room temperature, expanding the potential of monolayer in-plane heterostructures for optoelectronic devices.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Physics, Applied
Masafumi Shimasaki, Taishi Nishihara, Naoki Wada, Zheng Liu, Kazunari Matsuda, Yasumitsu Miyata, Yuhei Miyauchi
Summary: We demonstrate anisotropic exciton drift-diffusion in a WS2x Se(2-2x) alloy monolayer with a gradually changing exciton energy caused by the spatial variation in the chalcogen composition ratio. The photoluminescence (PL) images under isotropic laser excitation are extended toward the lower exciton energy side. Moreover, the degree of asymmetry in the PL image increases at the positions with a steep exciton energy gradient. The anisotropy in the PL images and its correlation with the exciton energy gradient are reproduced considering the exciton kinetics obeying a drift-diffusion equation.
APPLIED PHYSICS EXPRESS
(2023)
Article
Physics, Applied
Hao Ou, Koshi Oi, Rei Usami, Takahiko Endo, Yasumitsu Miyata, Jiang Pu, Taishi Takenobu
Summary: In this study, heterostructures of TMDCs and hBN were successfully fabricated into light-emitting devices. Monolayer and artificially stacked homobilayer WS2 were prepared on hBN, respectively. Both devices showed clear electroluminescence with voltages of similar to 3 V. The results indicate the enhancement of the optical performance of TMDCs and the potential expansion of TMDC-based light-emitting devices.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Hiroo Suzuki, Misaki Kishibuchi, Masaaki Misawa, Kazuma Shimogami, Soya Ochiai, Takahiro Kokura, Yijun Liu, Ryoki Hashimoto, Zheng Liu, Kenji Tsuruta, Yasumitsu Miyata, Yasuhiko Hayashi
Summary: Transition metal dichalcogenides (TMDCs) are promising 2D materials for optoelectronic devices and physics advancements. This study successfully synthesized long WxOy nanowires and grew monolayer WS2 nanoribbons on their surface. The developed method demonstrated high monolayer selectivity and enabled the growth of long WS2 nanoribbons with desired electronic properties. These findings have potential applications in future optoelectronic devices and advanced physics research.
Article
Chemistry, Multidisciplinary
Hiroto Ogura, Seiya Kawasaki, Zheng Liu, Takahiko Endo, Mina Maruyama, Yanlin Gao, Yusuke Nakanishi, Hong En Lim, Kazuhiro Yanagi, Toshifumi Irisawa, Keiji Ueno, Susumu Okada, Kosuke Nagashio, Yasumitsu Miyata
Summary: In-plane heterostructures of TMDCs have been fabricated through CVD, and their optical and electrical properties have been investigated. Multilayer TMDCs are a promising component for solving the low dielectric issue of monolayers. The formation of multilayer TMDC-based in-plane heterostructures and the vertical growth of MoS2 on the exfoliated flakes have been achieved.
Article
Chemistry, Multidisciplinary
Ryusuke Natsui, Hiroshi Shimizu, Yusuke Nakanishi, Zheng Liu, Akito Shimamura, Nguyen Tuan Hung, Yung-Chang Lin, Takahiko Endo, Jiang Pu, Iori Kikuchi, Taishi Takenobu, Susumu Okada, Kazu Suenaga, Riichiro Saito, Yasumitsu Miyata
Summary: This study presents a versatile method to fabricate nanoscale-thick bundles of indium-intercalated tungsten hexachalcogenide (W6Te6) wires. These bundles exhibit metallic behavior and mechanical flexibility, making them promising building blocks for integrated nanocircuits.
Article
Nanoscience & Nanotechnology
Wen Hsin Chang, Shogo Hatayama, Yuta Saito, Naoya Okada, Takahiko Endo, Yasumitsu Miyata, Toshifumi Irisawa
Summary: This work demonstrates the fabrication of atomically aligned van der Waals junctions through thermal-induced crystallization of layered Sb2Te3 electrodes on monolayer MoS2. The Sb2Te3/W contact shows better device performance on MoS2 MOSFETs compared to the Sb/W contact. The ideal vdW junctions exhibit extreme high-thermal robustness.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Wannes Peeters, Shuichi Toyouchi, Yasuhiko Fujita, Mathias Wolf, Beatrice Fortuni, Eduard Fron, Tomoko Inose, Johan Hofkens, Takahiko Endo, Yasumitsu Miyata, Hiroshi Uji-i
Summary: Tip-enhanced photoluminescence (TEPL) microscopy overcomes the diffraction-limited background signal by using remote excitation, achieving higher spatial resolution. Two probe designs were evaluated, and spatial heterogeneity was successfully demonstrated on a MoSe2/WSe2 lateral heterostructure.
Article
Engineering, Electrical & Electronic
Akichika Kumatani, Hiroto Ogawa, Takahiko Endo, Yu Kobayashi, Jana Lustikova, Hiroki Ida, Yasufumi Takahashi, Tomokazu Matsue, Yasumitsu Miyata, Hitoshi Shiku
Summary: The ability of two-dimensional, layered transition-metal dichalcogenides (TMDs) in promoting hydrogen evolution reaction (HER) has garnered much attention for hydrogen-generation applications. A study using scanning electrochemical cell microscopy (SECCM) to visualize and quantify the electrochemical HER activities of tungsten disulfide (WS2) islands revealed that the HER correlated current distribution is affected by the number of WS2 layers. SECCM imaging provides insights for future designs in TMD-based electrocatalysts.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY 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
Hiroto Ogura, Seiya Kawasaki, Zheng Liu, Takahiko Endo, Mina Maruyama, Yanlin Gao, Yusuke Nakanishi, Hong En Lim, Kazuhiro Yanagi, Toshifumi Irisawa, Keiji Ueno, Susumu Okada, Kosuke Nagashio, Yasumitsu Miyata
Summary: In-plane heterostructures of transition metal dichalcogenides (TMDCs) have been extensively studied for their high-performance electronic and optoelectronic devices. Currently, monolayer-based in-plane heterostructures prepared by chemical vapor deposition (CVD) have been explored, but their low dielectric properties limit their potential applications. In this study, we demonstrate the fabrication and transport properties of multilayer TMDC-based in-plane heterostructures, which show promising potential for various electronic devices. We also observe vertical growth of TMDCs on exfoliated flakes, further expanding their potential applications.
