Spin and lattice dynamics in the van der Waals antiferromagnet MnPSe

Liao, J.*; Huang, Z.*; Shangguan, Y.*; Zhang, B.*; Cheng, S.*; Xu, H.*; Kajimoto, Ryoichi; Kamazawa, Kazuya*; Bao, S.*; Wen, J.*

Physical Review B, 109(22), p.224411_1 - 224411_10, 2024/06

https://doi.org/10.1103/PhysRevB.109.224411

Pressure engineering of van der Waals compound RhI; Bandgap narrowing, metallization, and remarkable enhancement of photoelectric activity

Fang, Y.*; Kong, L.*; Wang, R.*; Zhang, Z.*; Li, Z.*; Wu, Y.*; Bu, K.*; Liu, X.*; Yan, S.*; Hattori, Takanori; et al.

Materials Today Physics (Internet), 34, p.101083_1 - 101083_7, 2023/05

https://doi.org/10.1016/j.mtphys.2023.101083

The layered van der Waals halides are particularly sensitive to external pressure, suggesting a feasible route to pinpoint their structure with extraordinary behavior. However, a very sensitive pressure response usually lead to a detrimental phase transition and/or lattice distortion, making the approach of materials manipulation in a continuous manner remain challenging. Here, the extremely weak interlayer coupling and high tunability of layered RhI crystals are observed. A pressure-driven phase transition occurs at a moderate pressure of 5 GPa, interlinking to a change of layer stack mode. Strikingly, such a phase transition does not affect the tendency of quasi-linear bandgap narrowing, and a metallization with an ultra-broad tunability of 1.3 eV redshift is observed at higher pressures. Moreover, the carrier concentration increases by 4 orders of magnitude at 30 GPa, and the photocurrent enhances by 5 orders of magnitude at 7.8 GPa. These findings create new opportunities for exploring, tuning, and understanding the van der Waals halides by harnessing their unusual feature of a layered structure, which is promising for future devices based on materials-by-design that are atomically thin.

Fine structure in the decay of the 8 isomer in U

Zhang, M. M.*; Tian, Y. L.*; Wang, Y. S.*; Zhang, Z. Y.*; Gan, Z. G.*; Yang, H. B.*; Huang, M. H.*; Ma, L.*; Yang, C. L.*; Wang, J. G.*; et al.

Physical Review C, 106(2), p.024305_1 - 024305_6, 2022/08

https://doi.org/10.1103/PhysRevC.106.024305

International network of nuclear structure and decay data evaluators

Dimitriou, P.*; Basunia, S*; Bernstein, L.*; Chen, J.*; Elekes, Z.*; Huang, X.*; Hurst, A.*; Iimura, Hideki; Jain, A. K.*; Kelley, J.*; et al.

EPJ Web of Conferences, 239, p.15004_1 - 15004_4, 2020/09

BB2020-0008.pdf:0.34MB

https://doi.org/10.1051/epjconf/202023915004

The Evaluated Nuclear Structure Data File (ENSDF) includes the most extensive and comprehensive set of nuclear structure and decay data evaluations performed by the international network of Nuclear Structure and Decay Data evaluators (NSDD) under the auspices of the IAEA. In this report we describe some of the recent NSDD activities and provide future perspectives.

Cooperative deformation in high-entropy alloys at ultralow temperatures

Naeem, M.*; He, H.*; Zhang, F.*; Huang, H.*; Harjo, S.; Kawasaki, Takuro; Wang, B.*; Lan, S.*; Wu, Z.*; Wang, F.*; et al.

Science Advances (Internet), 6(13), p.eaax4002_1 - eaax4002_8, 2020/03

https://doi.org/10.1126/sciadv.aax4002

Development of a new continuous dissolution apparatus with a hydrophobic membrane for superheavy element chemistry

Oe, Kazuhiro*; Attallah, M. F.*; Asai, Masato; Goto, Naoya*; Gupta, N. S.*; Haba, Hiromitsu*; Huang, M.*; Kanaya, Jumpei*; Kaneya, Yusuke*; Kasamatsu, Yoshitaka*; et al.

Journal of Radioanalytical and Nuclear Chemistry, 303(2), p.1317 - 1320, 2015/02

https://doi.org/10.1007/s10967-014-3469-3

A new technique for continuous dissolution of nuclear reaction products transported by a gas-jet system was developed for superheavy element (SHE) chemistry. In this technique, a hydrophobic membrane is utilized to separate an aqueous phase from the gas phase. With this technique, the dissolution efficiencies of short-lived radionuclides of Mo and W were measured. Yields of more than 80% were observed for short-lived radionuclides at aqueous-phase flow rates of 0.1-0.4 mL/s. The gas flow-rate had no influence on the dissolution efficiency within the studied flow range of 1.0-2.0 L/min. These results show that this technique is applicable for on-line chemical studies of SHEs in the liquid phase.

Effect of hydrogen termination on carbon -edge X-ray absorption spectra of nanographene

Hou, Z.*; Wang, X.*; Ikeda, Takashi; Huang, S.-F.*; Terakura, Kiyoyuki*; Boero, M.*; Oshima, Masaharu*; Kakimoto, Masaaki*; Miyata, Seizo*

Journal of Physical Chemistry C, 115(13), p.5392 - 5403, 2011/03

https://doi.org/10.1021/jp110879d

Carbon -edge X-ray absorption spectra of nanographene have been simulated by density functional theory calculations in order to obtain the information on the edge termination by hydrogen. Our results show that different edge terminations significantly affect the binding energy of 1s core-level of C atoms in the vicinity of edges because of the change in chemical bonding and the localized edge states. We find that a shoulder or a peak appears below the peak at relatively different positions with respect to the peak position in the theoretical spectra of zigzag graphene nano-ribbons, depending on the ratio of mono-hydrogen- to di-hydrogen-terminations. We also point out that the two additional features observed between the and peaks of an ideal graphene originate from the states of C-H bonding and C-H bonding at the edges.

Mechanisms of catalytic activity for carbon alloy catalysts

Ikeda, Takashi; Huang, S.-F.*; Boero, M.*; Terakura, Kiyoyuki*

Hakkin Daitai Kabon Aroi Shokubai, p.121 - 138, 2010/04

no abstracts in English

First-principles calculation of the electronic properties of graphene clusters doped with nitrogen and boron; Analysis of catalytic activity for the oxygen reduction reaction

Huang, S.-F.*; Terakura, Kiyoyuki*; Ozaki, Taisuke*; Ikeda, Takashi; Boero, M.*; Oshima, Masaharu*; Ozaki, Junichi*; Miyata, Seizo*

Physical Review B, 80(23), p.235410_1 - 235410_12, 2009/12

https://doi.org/10.1103/PhysRevB.80.235410

Recent studies suggest that the carbon-alloy catalyst with doped nitrogen may be a powerful candidate for cathode catalyst of fuel cell. In this paper, we aim to clarify the microscopic mechanisms of the enhancement in the catalyst activity caused by nitrogen doping using a simple graphene cluster model. We analyze modifications in the electronic structures and the energetical stability for some different configurations of N doping. We extend the analysis to the case of co-doping of nitrogen and boron and propose two possible scenarios explaining the further enhancement of catalytic activity by N and B co-doping.

Carbon alloy catalysts; Active sites for oxygen reduction reaction

Ikeda, Takashi; Boero, M.*; Huang, S.-F.*; Terakura, Kiyoyuki*; Oshima, Masaharu*; Ozaki, Junichi*

Journal of Physical Chemistry C, 112(38), p.14706 - 14709, 2008/09

https://doi.org/10.1021/jp806084d

Nitrogen-doped carbon-based catalysts are attracting a renovated interest as potential Pt-free electrode catalysts for polymer electrolyte fuel cell. In this computational study, we inspect possible oxygen adsorption and reduction processes on various models for the exposed edges of these catalysts. The dynamics of an O molecule solvated in water, mimicking the cathode environment, shows that O adsorption depends on the morphology and atomic structure of the system. We show that carbon alloys with N dopants at specific sites can exhibit a metal-free catalytic activity.