Updated on 2024/10/01

写真a

 
ANG, Artoni Kevin Roquero
 
Organization
Graduate School of Engineering Department of Advanced Science and Technology Materials Science and Engineering Energy Materials Laboratory Commissioned Researcher   
Degree
Ph.D ( Nara Institute of Science and Technology )
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Contact information
メールアドレス

Research Areas

  • Nanotechnology/Materials / Applied physical properties  / Thermoelectric materials, thermoelectric generation

Main research papers

Research History

  • Toyota Technological Institute   Postdoctoral researcher

    2021.10

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    Country:Japan

  • Nagoya Institute of Technology   Postdoctoral researcher

    2017.4 - 2021.9

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    Country:Japan

  • Nara Institute of Science and Technology   Postdoctoral researcher

    2016.10 - 2017.3

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    Country:Japan

  • Ateneo de Manila University   Department of Physics   Instructor

    2013.4 - 2013.10

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    Country:Philippines

  • Ateneo de Manila University   Department of Physics   Assistant Instructor

    2012.6 - 2013.3

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    Country:Philippines

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Education

  • Nara Institute of Science and Technology   Department of Material Science   Ph.D. in Materials Science

    2013.10 - 2016.9

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    Country: Japan

  • Ateneo de Manila University   Department of Physics   M.S. in Physics

    2010.6 - 2013.3

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    Country: Philippines

  • Ateneo de Manila University   Department of Physics   B.S. in Physics

    2006.6 - 2010.3

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    Country: Philippines

Professional Memberships

  • Japanese Society of Applied Physics

    2019.8

  • The Physical Society of Japan

    2014.3

Papers

  • Improvement of thermoelectric performance of flexible compound Ag2S0.55Se0.45 by means of partial V-substitution for Ag Reviewed

    Kosuke Sato, Saurabh Singh, Itsuki Yamazaki, Keisuke Hirata, Artoni Kevin R. Ang, Masaharu Matsunami, Tsunehiro Takeuchi

    AIP Advances   13 ( 12 )   2023.12 (     eISSN:2158-3226 )

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    Publishing type:Research paper (scientific journal)   Publisher:AIP Publishing  

    The effects of the partial V-substitution for Ag on the thermoelectric (TE) properties are investigated for a flexible semiconducting compound Ag2S0.55Se0.45. Density functional theory calculations predict that such a partial V-substitution constructively modifies the electronic structure near the bottom of the conduction band to improve the TE performance. The synthesized Ag1.97V0.03S0.55Se0.45 is found to possess a TE dimensionless figure-of-merit (ZT) of 0.71 at 350 K with maintaining its flexible nature. This ZT value is relatively high in comparison with those reported for flexible TE materials below 360 K. The increase in the ZT value is caused by the enhanced absolute value of the Seebeck coefficient with less significant variation in electrical resistivity. The high ZT value with the flexible nature naturally allows us to employ the Ag1.97V0.03S0.55Se0.45 as a component of flexible TE generators.

    DOI: 10.1063/5.0171888

  • Development of Cu2Se/Ag2(S,Se)-Based Monolithic Thermoelectric Generators for Low-Grade Waste Heat Energy Harvesting Reviewed

    Artoni Kevin R. Ang, Itsuki Yamazaki, Keisuke Hirata, Saurabh Singh, Masaharu Matsunami, Tsunehiro Takeuchi

    ACS Applied Materials & Interfaces   15 ( 40 )   46962 - 46970   2023.9 (   ISSN:1944-8244   eISSN:1944-8252 )

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    Authorship:Lead author   Publishing type:Research paper (scientific journal)   Publisher:American Chemical Society (ACS)  

    DOI: 10.1021/acsami.3c09823

  • Enhanced Performance of Monolithic Chalcogenide Thermoelectric Modules for Energy Harvesting via Co-optimization of Experiment and Simulation Reviewed

    ACS Applied Materials & Interfaces   14   38642   2022.8

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    Publishing type:Research paper (scientific journal)   Publisher:American Chemical Society  

    DOI: 10.1021/acsami.2c06349

  • Thermoelectric performance of Fe2V0.9W0.1Al thin films deposited on n-type Si substrates Reviewed

    Fahmi Machda, Saurabh Singh, Kentaro Kuga, Artoni Kevin Roquero Ang, Masaharu Matsunami, Tsunehiro Takeuchi

    Japanese Journal of Applied Physics   2023.4

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    Publishing type:Research paper (scientific journal)  

    DOI: 10.35848/1347-4065/accfd7

  • Direct Observation of Group-V Dopant Substitutional Defects in CdTe Single Crystals Reviewed

    Akira Nagaoka*, Koji Kimura*, Artoni Kevin R. Ang, Yasuhiro Takabayashi*, Kenji Yoshino*, Qingde Sun*, Baoying Dou*, Su-Huai Wei*, Koichi Hayashi*, Kensuke Nishioka*

    Journal of the American Chemical Society   145 ( 16 )   9191 - 9197   2023.4

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:American Chemical Society  

    DOI: https://doi.org/10.1021/jacs.3c01248

  • Development of serial X-ray fluorescence holography for radiation-sensitive protein crystals. Reviewed

    Artoni Kevin R Ang, Yasufumi Umena*, Ayana Sato-Tomita*, Naoya Shibayama*, Naohisa Happo*, Riho Marumi*, Yuta Yamamoto*, Koji Kimura*, Naomi Kawamura*, Yu Takano*, Tomohiro Matsushita*, Yuji C Sasaki*, Jian Ren Shen*, Kouichi Hayashi*

    Journal of synchrotron radiation   30 ( Pt 2 )   368 - 378   2023.3

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

    X-ray fluorescence holography (XFH) is a powerful atomic resolution technique capable of directly imaging the local atomic structure around atoms of a target element within a material. Although it is theoretically possible to use XFH to study the local structures of metal clusters in large protein crystals, the experiment has proven difficult to perform, especially on radiation-sensitive proteins. Here, the development of serial X-ray fluorescence holography to allow the direct recording of hologram patterns before the onset of radiation damage is reported. By combining a 2D hybrid detector and the serial data collection used in serial protein crystallography, the X-ray fluorescence hologram can be directly recorded in a fraction of the measurement time needed for conventional XFH measurements. This approach was demonstrated by obtaining the Mn Kα hologram pattern from the protein crystal Photosystem II without any X-ray-induced reduction of the Mn clusters. Furthermore, a method to interpret the fluorescence patterns as real-space projections of the atoms surrounding the Mn emitters has been developed, where the surrounding atoms produce large dark dips along the emitter-scatterer bond directions. This new technique paves the way for future experiments on protein crystals that aim to clarify the local atomic structures of their functional metal clusters, and for other related XFH experiments such as valence-selective XFH or time-resolved XFH.

    DOI: 10.1107/S1600577522011833

  • Atomic positions and displacements in piezoelectric materials Ca3TaGa3Si2O14 and Ca3TaGa1.5Al1.5Si2O14 investigated by Ta-Lα X-ray fluorescence holography Reviewed

    Mamoru Kitaura*, Artoni Kevin R. Ang, Yuta Yamamoto*, Naohisa Happo*, Koji Kimura*, Kouichi Hayashi*, Shinta Watanabe*, Yuui Yokota*, Yuji Ohashi*, Kei Kamada*, Akira Yoshikawa*, Hisanori Yamane*, Akimasa Ohnishi*

    Frontiers in Materials   9   2022.9 (     eISSN:2296-8016 )

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    Language:English   Publishing type:Research paper (scientific journal)  

    The atomic positions and displacements of atoms around the Ta atom in piezoelectric materials Ca3TaGa3Si2O7 (CTGS) and Ca3TaGa1.5Al1.5Si2O7 (CTGAS) were investigated at 100 K by Ta-Lα X-ray fluorescence holography (XFH). The experimental atomic images were compared with the simulated ones using the crystal structures of CTGS and CTGAS, which were determined by single crystal X-ray diffractometry (SC-XRD). The atomic positions agreed between XFH and SC-XRD experiments. With the help of XFH simulation, the displacements of Ta, Ca, Si, and Ga atoms relative to the Ta atom were qualitatively analyzed using experimental atomic image intensities. The relative displacement of the Ca atom was increased by Al substitution, while those of the Ta and Ga atoms were decreased. The first principles calculation based on density-functional theory (DFT) was performed to understand bonding character between constituents. The evaluation of the crystal orbital Hamilton population (COHP) clarified that the Ca-O bond has strong ionic character different with the other bonds, suggesting that the positional shift of the Ca atom is responsible for the piezoelectricity in CTGS. The effect of Al substitution on piezoelectricity was also considered based on the change in the Ca-O bond.

    DOI: 10.3389/fmats.2022.977371

  • Element-selective local structural analysis around B -site cations in multiferroic Pb ( Fe 1 / 2 Nb 1 / 2 ) O 3 using x-ray fluorescence holography Reviewed

    K. Kimura*, D. Urushihara*, R. Kondo*, Y. Yamamoto*, A.K.R. Ang, T. Asaka*, N. Happo*, T. Hagihara*, T. Matsushita*, H. Tajiri*, H. Miyazaki*, K. Ohara*, M. Iwata*, and K. Hayashi*

    104   144101   2021.10

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    Publishing type:Research paper (scientific journal)  

    DOI: 10.1103/PhysRevB.104.144101

  • Anion arrangement analysis of oxynitride perovskite thin film with inverse photoelectron holography Reviewed

    Y. Yamamoto*, A.K.R. Ang, K. Kimura*, T. Matsushita*, Y. Hirose*, D. Oka*, K. Hayashi*

    Journal of Electron Spectroscopy and Related Phenomena   246   147018 - 147018   2021.1

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    Publishing type:Research paper (scientific journal)   Publisher:Elsevier {BV}  

    DOI: 10.1016/j.elspec.2020.147018

  • Local structure and atomic dynamics in Fe2VAl Heusler-type thermoelectric material: The effect of heavy element doping Reviewed

    K. Kimura*, K. Yamamoto*, K. Hayashi*, S. Tsutsui*, N. Happo*, S. Yamazoe*,H. Miyazaki*,S. Nakagami*,J.R. Stellhorn*,S. Hosokawa*,T. Matsushita*, H. Tajiri*,A.K.R. Ang, Y. Nishino*

    Physical Review B   101 ( 2 )   2020

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    Publishing type:Research paper (scientific journal)  

    DOI: 10.1103/PhysRevB.101.024302

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Presentations

  • Low temperature sintering of chalcogenide-based monolithic thermoelectric generators for energy harvesting applications International conference

    Artoni Kevin R. Ang, Itsuki Yamazaki, Saurabh Singh, Masaharu Matsunami ,Tsunehiro Takeuchi

    MRM2023/IUMRS-ICA2023 Grand Meeting  ( Kyoto International Conference Center )   2023.12 

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    Event date: 2023.12

    Presentation type:Oral presentation (general)  

  • Optimization of device parameters in the chalcogenide-based multilayer monolithic thermoelectric generators International conference

    Artoni Kevin R. Ang, Itsuki Yamazaki, Saurabh Singh, Masaharu Matsunami and Tsunehiro Takeuchi

    apanese Society for Applied Physics 71st Spring Meeting  ( Tokyo City University )   2024.3 

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    Event date: 2024.3

    Presentation type:Oral presentation (general)  

  • Development of Cu2Se/Ag2(S,Se)-based monolithic chalcogenide thermoelectric generators for energy harvesting applications

    Artoni Kevin R. Ang, Itsuki Yamazaki, Saurabh Singh, Masaharu Matsunami and Tsunehiro Takeuchi

    apanese Society for Applied Physics 84th Autumn Meeting  ( Kumamoto-jo Hall )   2023.9 

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    Event date: 2023.9

    Presentation type:Oral presentation (general)  

  • 積層型熱電発電素子の開発 International conference

    山崎樹*, ANG, Artoni Kevin Roquero, 平田圭佑*, 松波 雅治, 竹内 恒博

    日本熱電学会2023年度春季第172回講演大会  ( 東京大学駒場キャンパス )   2023.3  日本金属学会

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    Presentation type:Oral presentation (general)  

  • Development of monolithic thermoelectric generators using high performance chalcogenide materials for ambient temperature applications International conference

    ANG, Artoni Kevin Roquero

    JSAP Autumn Meeting 2022  ( 東北大学 )   2022.9 

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    Presentation type:Oral presentation (general)  

    The generation of electricity from waste heat using thermoelectric (TE) materials is one of the cleanest forms of renewable energy. Typical commercial TE generators (TEG) use a π-type structure, where p- and n-type TE legs are bridged by a metal interconnect. As an improvement to this device architecture, a monolithic multilayer design was developed to remove the need for metal interconnects and the unnecessary empty spaces in between TE legs to get a robust, densely packed TEG.
    In this work, we fabricate monolithic TEGs by co-sintering chalcogenide materials with exceptional near room temperature TE properties. The TE devices were fabricated by co-sintering thin layers of p- and n- legs, with an insulating layer partially inserted between. Ag- and Cu- chalcogenide materials were used as the p-type, insulating spacer, and n-type materials.
    The TEG structure was designed and optimized using finite element method (FEM) using the COMSOL Multiphysics software. The actual devices were fabricated using a low energy cost method, by assembling the different layers and co-sintering at temperatures below 373K with an applied uniaxial pressure of 200 MPa.
    The structures of the TEG devices were characterized using SEM and EPMA, and the power generation were measured using a TEG device measurement setup. The power output shows that these devices can be used as power sources for small sensors in various internet-of-things (IoT) applications.

  • Development of monolithic thermoelectric generators using high performance chalcogenide materials for ambient temperature applications International conference

    ANG, Artoni Kevin Roquero, 山﨑樹*, 平田圭佑*, Saurabh Singh*, 松波 雅治, 竹内 恒博

    第83回応用物理学会秋季学術講演会  ( 東北大学 川内北キャンパス+オンライン )   2022.9 

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    Presentation type:Oral presentation (general)  

  • Cold sintering of monolithic multilayer thermoelectric devices using chalcogenide thermoelectric materials International conference

    ANG, Artoni Kevin Roquero

    69th JSAP Spring Meeting 2022  ( Online )   2022.3 

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    Presentation type:Oral presentation (general)  

  • X-ray fluorescence holography of X-ray irradiation defects in κ-(BEDT-TTF)2Cu[N(CN)2]Br International conference

    ANG, Artoni Kevin Roquero

    JPS Autumn Meeting 2021  ( Online )   2021.9 

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Awards

  • Research Encouragement Award

    2024.3   Toyota Scholarship Fund   Development of novel thermoelectric generators for ambient temperature energy harvesting

Grant-in-Aid for Scientific Research