Thermal response and visible light photocatalytic reactivity of He induced nanostructure tungsten

• Project/Area Number: 17KK0132
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research)
• Allocation Type: Multi-year Fund
• Research Field: Nuclear fusion studies
• Research Institution: The University of Tokyo (2021-2022); Nagoya University (2017-2020)
• Principal Investigator: Kajita Shin 東京大学, 大学院新領域創成科学研究科, 教授 (00455297)
• Project Period (FY): 2018 – 2022
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥13,650,000 (Direct Cost: ¥10,500,000、Indirect Cost: ¥3,150,000)
• Keywords: プラズマ / ヘリウム / ファズ / 光電気化学 / ニューラルネットワーク / 分光 / 機械学習 / 分光計測 / 共堆積 / ナノ構造 / タングステン / プラズマ計測 / 鉄酸化物 / 光触媒 / 金属ナノ構造 / 核融合

Outline of Final Research Achievements

Experiments were conducted using the linear device MAGNUM-PSI to irradiate tungsten with helium and deposit tungsten at the same time. While fuzz growth was suppressed when copper and molybdenum were deposited, a fuzz layer as thick as 7 μm was formed when a tungsten sputtering source was placed near the sample, suggesting that the fuzz growth rate was significantly accelerated by the tungsten deposition. In addition, the relationship between ne and Te from laser Thomson scattering and OES data in Magnum-PSI was modeled using a neural network to evaluate the error in temperature and density measurements, and it was found that the measurement error was about 10%.

Academic Significance and Societal Importance of the Research Achievements

今後，この方法は，レーザートムソン散乱が利用できない場合においてもneとTeの測定領域を拡張することが可能である。例えば，より高速な検出器を用いれば，レーザーパルス周波数（現時点では10 Hz）で決まるトムソン散乱よりも高い時間分解能が得られ，ハイパースペクトル画像と組み合わせることで二次元計測も可能になる。さらに，機械学習を用いた研究を進めることで，衝突輻射モデルで得られた分布からのずれを引き起こす過程を発見できる可能性がある。本手法は大型装置においても分光計測のデータを用いて高い精度で電子温度や密度を計測できる可能性があり，トムソン散乱などに比べて極めて安価な手法となる。

Research Products

• [Int'l Joint Research] ITER機構(フランス) (2022)
• [Int'l Joint Research] IPP Greifswald, Max-Planck Institute for Plasma Physics(ドイツ) (2018)
  • Year and Date: 2018-10-01
• [Int'l Joint Research] DIFFER (Dutch Institute for Fundamental Energy Research)(オランダ) (2018)
• [Journal Article] Increased Photoelectrochemical Performance of Vanadium Oxide Thin Film by Helium Plasma Treatment with Auxiliary Molybdenum Deposition (2023)
  • Author(s): Kajita Shin、Eda Tomoki、Feng Shuangyuan、Tanaka Hirohiko、Bieberle-H?tter Anja、Ohno Noriyasu
  • Journal Title: Advanced Energy and Sustainability Research Volume: 4 Issue: 3 Pages: 2200141-2200141
  • DOI: 10.1002/aesr.202200141
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Use of machine learning for a helium line intensity ratio method in Magnum-PSI (2022)
  • Author(s): Kajita Shin、Iwai Sho、Tanaka Hirohiko、Nishijima Daisuke、Fujii Keisuke、van der Meiden Hennie、Ohno Noriyasu
  • Journal Title: Nuclear Materials and Energy Volume: 33 Pages: 101281-101281
  • DOI: 10.1016/j.nme.2022.101281
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Photoelectrochemical properties of plasma-induced nanostructured tungsten oxide (2022)
  • Author(s): Feng Shuangyuan、Kajita Shin、Higashi Masanobu、Bieberle-H?tter Anja、Yoshida Tomoko、Ohno Noriyasu
  • Journal Title: Applied Surface Science Volume: 580 Pages: 151979-151979
  • DOI: 10.1016/j.apsusc.2021.151979
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Investigation of Light Transmission Efficiency in ITER Hard X-Ray Monitor (2021)
  • Author(s): KAJITA Shin、PANDYA Santosh P.、O'CONNOR Richard、BARNSLEY Robin、ROGER Huxford
  • Journal Title: Plasma and Fusion Research Volume: 16 Issue: 0 Pages: 1302106-1302106
  • DOI: 10.1585/pfr.16.1302106
  • NAID: 130008130034
  • ISSN: 1880-6821
  • Year and Date: 2021-12-10
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Application of multiple regression for sensitivity analysis of helium line emissions to the electron density and temperature in Magnum-PSI (2021)
  • Author(s): Kajita Shin、Nishijima Daisuke、Fujii Keisuke、Akkermans Gijs、van der Meiden Hennie
  • Journal Title: Plasma Physics and Controlled Fusion Volume: 63 Issue: 5 Pages: 055018-055018
  • DOI: 10.1088/1361-6587/abf36e
  • NAID: 120007169533
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Plasma-wall interaction studies in W7-X: main results from the recent divertor operations (2021)
  • Author(s): Dhard C P、Brezinsek S、Mayer M、Naujoks D、Masuzaki S、Zhao D、Yi R、Oelmann J、Schmid K、Romazanov J、Pardanaud C、Kandler M、Kharwandikar A K、Schlisio G、Volzke O、Grote H、Gao Y、Rudischhauser L、Goriaev A、Wauters T、Kirschner A、Sereda S、Wang E、Rasinski M、Dittmar T、Motojima G、Hwangbo D et al.,
  • Journal Title: Physica Scripta Volume: 96 Issue: 12 Pages: 124059-124059
  • DOI: 10.1088/1402-4896/ac35c0
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Accelerated/reduced growth of tungsten fuzz by deposition of metals (2021)
  • Author(s): Kajita Shin、Morgan Thomas、Tanaka Hirohiko、Hayashi Yuki、Yoshida Naoaki、Nagata Daisuke、Vernimmen Jordy、Feng Shuangyuan、Zhang Rongshi、Ohno Noriyasu
  • Journal Title: Journal of Nuclear Materials Volume: 548 Pages: 152844-152844
  • DOI: 10.1016/j.jnucmat.2021.152844
  • NAID: 120007191867
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Inspection of Arc Trails Formed in Stellarator/Heliotron Devices W7-X and LHD (2020)
  • Author(s): HWANGBO Dogyun、KAJITA Shin、DHARD Chandra Prakash、TOKITANI Masayuki、KRAUSE Marco、NAUJOKS Dirk、MASUZAKI Suguru、KLOSE S?ren、OHNO Noriyasu、The W7-X Team
  • Journal Title: Plasma and Fusion Research Volume: 15 Issue: 0 Pages: 2402012-2402012
  • DOI: 10.1585/pfr.15.2402012
  • NAID: 130007840524
  • ISSN: 1880-6821
  • Year and Date: 2020-03-27
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Ray tracing study of ITER in-vessel lighting system (2020)
  • Author(s): Kajita Shin、Passedat Gilles、Reichle Roger
  • Journal Title: Fusion Engineering and Design Volume: 160 Pages: 111787-111787
  • DOI: 10.1016/j.fusengdes.2020.111787
  • NAID: 120007163655
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Dust Formation from Arc Spots on Nanostructured Tungsten Surface (2020)
  • Author(s): YAJIMA Miyuki、KAJITA Shin、OHNO Noriyasu、MASUZAKI Suguru、YOSHIDA Naoaki、AUSSEMS Damien U. B.、MORGAN Thomas W.、BYSTROV Kirill、MEIDEN Hennie van der
  • Journal Title: Plasma and Fusion Research Volume: 15 Issue: 0 Pages: 1205061-1205061
  • DOI: 10.1585/pfr.15.1205061
  • NAID: 130007888614
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Cross-field transport in detached helium plasmas in Magnum-PSI (2020)
  • Author(s): Tanaka H、Hayashi Y、Kajita S、van der Meiden H J、Yoshikawa M、Vernimmen J W M、Scholten J、Classen I、Morgan T W、Ohno N
  • Journal Title: Plasma Physics and Controlled Fusion Volume: 62 Issue: 11 Pages: 115021-115021
  • DOI: 10.1088/1361-6587/abb88f
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Helium irradiation effects on the surface modification and recrystallization of tungsten (2020)
  • Author(s): Khan A、De Temmerman G、Kajita S、Greuner H、Balden M、Hunger K、Ohno N、Hwangbo D、Tomita Y、Tokitani M、Nagata D、Yajima M
  • Journal Title: Physica Scripta Volume: T171 Pages: 014050-014050
  • DOI: 10.1088/1402-4896/ab52c6
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Inspection of W 7-X plasma-facing components after the operation phase OP1.2b: observations and first assessments (2020)
  • Author(s): Dhard C P、?k?slompolo S、Balden M、Baldzuhn J、Biedermann C、Br?uer T、Brezinsek S、Endler M、Hayashi Y、Hwangbo D、Kajita S、Krause M、Kornejew P、Masuzaki S、Mayer M、Motojima G、Naujoks D、Otte M、Rohde V、the W7-X Team
  • Journal Title: Physica Scripta Volume: T171 Pages: 014033-014033
  • DOI: 10.1088/1402-4896/ab4b3f
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Emission spectroscopy of He lines in high-density plasmas in Magnum-PSI (2020)
  • Author(s): Kajita Shin、Akkermans Gijs、Fujii Keisuke、van der Meiden Hennie、van de Sanden M. C. M.
  • Journal Title: AIP Advances Volume: 10 Issue: 2 Pages: 025225-025225
  • DOI: 10.1063/1.5143481
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Enhanced fuzzy tungsten growth in the presence of tungsten deposition (2020)
  • Author(s): McCarthy Patrick、Hwangbo Dogyun、Bilton Matthew、Kajita Shin、Bradley James W.
  • Journal Title: Nuclear Fusion Volume: 60 Issue: 2 Pages: 026012-026012
  • DOI: 10.1088/1741-4326/ab6060
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Application of Ion Sensitive Probe to High Density Plasmas in Magnum-PSI (2019)
  • Author(s): HAYASHI Yuki、OHNO Noriyasu、van der MEIDEN Hennie、SCHOLTEN John、KAJITA Shin、van den BERG Jonathan、PERILLO Renato、VERNIMMEN Jordy、MORGAN Thomas
  • Journal Title: Plasma and Fusion Research Volume: 14 Issue: 0 Pages: 1202135-1202135
  • DOI: 10.1585/pfr.14.1202135
  • NAID: 130007695127
  • ISSN: 1880-6821
  • Year and Date: 2019-07-24
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Ray Trace Study for Visible Spectroscopy Reference System (VSRS) Diagnostics in ITER (2019)
  • Author(s): KAJITA Shin、DE BOCK Maarten、DESJARDINS Michel、BARNSLEY Robin
  • Journal Title: Plasma and Fusion Research Volume: 14 Issue: 0 Pages: 1405042-1405042
  • DOI: 10.1585/pfr.14.1405042
  • NAID: 130007649950
  • ISSN: 1880-6821
  • Year and Date: 2019-02-25
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Influence of heavier impurity deposition on surface morphology development and sputtering behavior explored in multiple linear plasma devices (2019)
  • Author(s): Nishijima D.、Kreter A.、Baldwin M.J.、Borodin D.、Eksaeva A.、Hwangbo D.、Kajita S.、Miyamoto M.、Ohno N.、Patino M.、Pospieszczyk A.、Rasinski M.、Schlummer T.、Terra A.、Doerner R.P.
  • Journal Title: Nuclear Materials and Energy Volume: 18 Pages: 67-71
  • DOI: 10.1016/j.nme.2018.12.008
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Thomson Scattering Measurement of Two Electron Temperature Components in Transition to Detached Plasmas (2018)
  • Author(s): OHSHIMA Hiroshi、KAJITA Shin、TANAKA Hirohiko、OHNO Noriyasu、VAN DER MEIDEN Hennie J.
  • Journal Title: Plasma and Fusion Research Volume: 13 Issue: 0 Pages: 1201099-1201099
  • DOI: 10.1585/pfr.13.1201099
  • NAID: 130007487813
  • ISSN: 1880-6821
  • Year and Date: 2018-08-10
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Assessment and Mitigation of Wall Light Reflection in ITER by Ray Tracing (2018)
  • Author(s): Kajita Shin、Veshchev Evgeny、De Bock Maarten、Barnsley Robin、Von Hellermann Manfred、Walsh Michael
  • Journal Title: Fusion Science and Technology Volume: 74 Issue: 1-2 Pages: 37-46
  • DOI: 10.1080/15361055.2017.1390389
  • NAID: 120006733923
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Growth of nano-tendril bundles on tungsten with impurity-rich He plasmas (2018)
  • Author(s): Hwangbo Dogyun、Kajita Shin、Ohno Noriyasu、McCarthy Patrick、Bradley James W.、Tanaka Hirohiko
  • Journal Title: Nuclear Fusion Volume: 58 Issue: 9 Pages: 096022-096022
  • DOI: 10.1088/1741-4326/aacd1f
  • Peer Reviewed / Int'l Joint Research
• [Presentation] Helium plasma induced fuzzy metal: growth mechanism and its application (2022)
  • Author(s): Shin Kajita
  • Organizer: AAPPS-DPP2022
  • Int'l Joint Research / Invited
• [Presentation] Photoelectrochemical Properties of Plasma-Induced Nanostructured WO3 (2021)
  • Author(s): S.Feng, S.Kajita, M.Higashi, A.Bieberle, T.Yoshida, N.Ohno
  • Organizer: ISPlasma2021/IC-PLANTS2021
  • Int'l Joint Research
• [Presentation] プラズマ誘起ナノ構造酸化タングステンの光触媒水分解への応用 (2020)
  • Author(s): 馮 双園、梶田 信、東 正信、Anja Bieberle、吉田朋子、大野哲靖
  • Organizer: プラズマ・核融合学会第37回年会
• [Presentation] Inspection of W 7-X plasma-facing components after the operation phase OP1. 2b: observations and first assessments (2019)
  • Author(s): CP Dhard, S Akaslompolo, M Balden, J Baldzuhn, C Biedermann, T Bruer, S Brezinsek, M Endler, Y Hayashi, D Hwangbo, S Kajita, M Krause, P Kornejew, S Masuzaki, M Mayer, G Motojima, D Naujoks, M Otte, V Rohde
  • Organizer: PFMC-17
  • Int'l Joint Research
• [Presentation] Inspection of Arc Trails Formed in Stellarator/Heliotron Devices W7-X and LHD (2019)
  • Author(s): Dogyun HWANGBO, Shin KAJITA, Chandra Prakash DHARD, Masayuki TOKITANI, Marco KRAUSE, Dirk NAUJOKS, Suguru MASUZAKI, Sren KLOSE, Noriyasu OHNO, The W7-X Team
  • Organizer: 28th International Toki Conference on Plasma and Fusion Research (ITC28)
  • Int'l Joint Research
• [Presentation] Influence of heavier impurity deposition on Cr sputtering under He plasma exposure in multiple linear plasma devices (2018)
  • Author(s): D.Nishijima, A.Kreter, R.P.Doerner, M.J.Baldwin, D.Borodin, A.Eksaeva, D.Hwangbo, S.Kajita, M.Miyamoto, N.Ohno, A.Pospieszczyk, M.Rasinski, T.Schlummer, A.Terra,
  • Organizer: PSI2018
  • Int'l Joint Research
• [Presentation] Influence of recombination front region on plasma detachment in a linear divertor plasma simulator (2018)
  • Author(s): N.Ohno, Y.Hayashi, S.Kajita, H.Tanaka, H.Ohshima, M.Seki, K.Sawada, M.Aramaki, M.Yoshikawa, H.J.van der Meiden
  • Organizer: PSI2018
  • Int'l Joint Research / Invited