Ibaraki University's
Graduate School of Science and Engineering (Engineering)
Department of Materials Science and Engineering



Other affiliation / position

  1. Frontier Research Center for Applied Atomic Sciences


  1. 花王株式会社 東京研究所 研究員 1991/04-1992/03
  2. 慶應義塾大学 理工学部 非常勤講師 1995/04-1995/10
  3. 新技術開発事業団 特別研究員 (派遣先:金属材料技術研究所) 1995/10-1998/03
  4. 茨城大学 工学部 物質工学科 助手 1998/04-2005/06
  5. 茨城大学 工学部 物質工学科 講師 2005/07-Present
  6. 茨城大学 工学部 生体分子機能工学科 講師 2006/07/01-2010/03/31
  7. 茨城大学 工学部 生体分子機能工学科 准教授 2010/04/01-2018/03/31
  8. 茨城大学 工学部 物質科学工学科 教授 2018/04/01-Present

Academic background

  1. Keio University Faculty of Science and Engineering Department of Applied Chemistry 1989 Graduated
  2. Keio University Graduate School, Division of Science and Engineering Applied of Chemistry Doctor course 1995 Completed 3-14-1, Hiyoshi,Kohoku-ku, yokohama

Academic degrees

  1. Ph.D Keio University

Research Areas

  1. Industrial Physical Chemistry
  2. Functional Materials/Device

Research keywords

  1. Fuel Cell
  2. Lithium ion battery

Subject of research

  1. Lithium Secondary Battery リチウム二次電池用正極材料の合成および評価 1995/04-Present
  2. 燃料電池に関する研究 2003-Present
  3. バイオセンサに関する研究 2005-2011

Proposed theme of joint or funded research

  1. Fuel Cell Wish to undertake joint research with industry and other organizations including private sector. Technical consultation,Commisioned research,Joint research,Others
  2. Lithium Secondary Battery Wish to undertake joint research with industry and other organizations including private sector. Technical consultation,Commisioned research,Others


  1. Fuel Cell Efficiency, A new nondestructive method for measuring flow rate distribution between cells by electrochemical techniques in an actual polymer electrolyte fuel cell stack Mika Eguchi, Fumihiko Sekinea, Yoshio Kobayashi, Yasuyuki Tsutsumi Nova Science Publishers, Inc. 2012/02/10 978-1-61209-619-3


  1. Research paper (scientific journal) Joint Quick crossover current measurement of a polymer electrolyte fuel cell stack with and without cell voltage terminals Hiroyuki Gunji, Mika Eguchi, Fumiaki Sekine, Yasuyuki Tsutsumi Journal of Power Sources 409, 6-12 2019/01/01
  2. (MISC) Introduction and explanation (scientific journal) Joint 新規球状炭素材料「マリモカーボン」の合成と応用 蒲生西谷 美香,中川 清晴,江口 美佳,安藤 寿浩 New Diamond ニューダイヤモンドフォーラム 34/ 4, 11-16 2018/10/30
  3. (MISC) Introduction and explanation (commerce magazine) マリモカーボンを用いた燃料電池用触媒の開発 江口 美佳,小田倉 圭祐,蒲生西谷 美香,安藤 寿浩 車載テクノロジー 技術情報協会 5/ 1, 51-56 2017/10/01
  4. Research paper (scientific journal) Joint Preparation of catalyst for polymer electrolyte fuel cell using the Marimo-like carbon Koki Baba, Mikka Nishitani-Gamo, Toshihiro Ando, Mika Eguchi Transactions of the Materials Research Society of Japan 42/ 2, 51-56 2017/04/03 We have investigated the influence of the concentrations of both the chloroplatinic acid and sodium borohydride solution on the formation of the Pt nanoparticles in this study.A lower chloroplatinic acid concentration and higher sodium borohydride concentration produced fine Pt particles with higher dispersion and better catalytic activity than other.
  5. Research paper (scientific journal) Joint Gas-leak-induced pinhole formation at polymer electrolyte membrane fuel cell electrode edges Hiroyuki Gunji, Mika Eguchi, Fumiaki Sekine, Yasuyuki Tsutsumi International Journal of Hydrogen Energy 42/ 1, 562-574 2017/01/05 Pinhole formation in the membrane is a polymer electrolyte membrane fuel cell (PEMFC) failure mode typically due to mechanical causes. This study reports the discovery of thermal pinhole formation caused by a gas leak. The study was prompted by an unexpected cell failure of a real PEMFC stack during its initial conditioning. A little gas leak had been detected in the stack, and the gas leak was suspected to generate pinholes. However, in spite of the large gas leak, pinholes did not appear in the normal cells with a GDL-covered catalyst layer. Additional cells with a GDL-uncovered catalyst layer simulating an uneven electrode edge of the failed stack were then tested under the gas leak conditions. Pinholes were demonstrated to appear at the GDL-uncovered catalyst layer position near the gas leak path during the initial conditioning and the phenomena were reproducible. A gas-leak-induced thermal pinhole formation is suggested in which the leaked gas hits the GDL-uncovered low-heat-dissipation catalyst, a hot spot occurs by catalytic combustion, generating the pinhole.

Research presentations

  1. Oral presentation(general) PEFC用白金担持マリモカーボン触媒の調製における白金源と還元剤の影響 電気化学会第87回大会 2020/03/17 PEFC用電極触媒においてカーボン上への小粒径で高分散な白金担持を目指して,触媒調製時の白金源と還元剤の組み合わせを検討した。触媒担体にはグラファイトシートが積層した繊維状炭素であるマリモカーボン(MC)を使用しており,白金が高分散担持可能であり,高い排水性と耐久性にも期待ができる。ナノコロイド溶液法による触媒調製条件における白金の担持状態を比較し,電気化学測定により性能を評価した。
  2. Poster presentation LIB負極用Li4Ti5O12/マリモカーボン複合体の合成と電気化学的特性 表面技術協会第141回講演大会 2020/03/03 新規炭素材料を用い,Li4Ti5O12負極の性能向上を目的とした。
  3. Oral presentation(general) Effect of platinum precursors and reducing agents on the formation of Pt particles onto the carbon nanofilaments, D-O27-011 第29回日本MRS年次大会 2019/11/27 Platinum can exhibit high catalytic activity as a catalyst for a polymer electrolyte fuel cell (PEFC). We applied the Marimo-like carbon (MC) as a catalyst support. The MC consisted of many carbon nano-filaments (CNFs), and played excellent role as an electrode and catalyst support. In this study, we investigated the effect of the platinum precursors and reducing agents on deposition of platinum particles on the CNFs of the MC in the modified nano-colloidal solution methods.
  4. Poster presentation Hydrothermal synthesis condition of the Li4Ti5O12/Marimo-like carbon composite, D-P27-005 第29回日本MRS年次大会 2019/11/27 We have studied to synthesize Li4Ti5O12 (LTO)/carbon composite as an anode material of lithium-ion battery to improve electric conductivity and to enhance electric charging capacity. The Marimo carbon (MC) has a sphere structure made of many fine carbon nanofilaments (CNFs), which grew radially from oxidized diamond1). In this study, we prepared the LTO/MC composites by hydrothermal method and investigated relation between the hydrothermal conditions and their charge/discharge characteristics.
  5. Oral presentation(general) Synthesis of the Marimo-like carbon using fluidized or fixed bed flow-reactor and their performances for lithium ion battery, D-O27-013 第29回日本MRS年次大会 2019/11/27 Marimo-like carbon (MC) consists of many carbon nanofilaments(CNFs) which grew radially from the oxidized diamond core. We have proved the MC to work as a conductive additive for active materials, spinel Li4Ti5O12(LTO), etc. In order to improve its performance, we have tried to reduced particle size of the MC using a new type flow-reactor.

Intellectual property rights

  1. Patent 触媒シートの製造方法,及び空気極の製造方法 2016-121868 2016/06/20
  2. Patent 触媒シートの製造方法,及び空気極の製造方法 2016-121869 2016/06/20
  3. Patent 触媒シート,及び空気極 2016-121870 2016/06/20
  4. Patent リチウム電池用電極活物質 2013-54384 2013/03/15 2014-177388 2014/09/25
  5. Patent マリモカーボンおよびその製造方法 2011-186146 2011/08/29 2013-47160 2013/03/07


  1. 表面技術協会 第12回学術奨励講演賞 2006/03/15

Alloted class

  1. 基礎化学
  2. Primary Aanalytical Chemistry
  3. Information Processing
  4. Basic Experiments for Bio-molecular Functional Engineering
  5. Life and Chemistry

Memberships of academic societies

  1. 電気化学会
  2. 表面技術協会
  3. The Electrochemical Society
  4. 日本化学会

Committee Career

  1. 日本化学会 関東支部幹事 2011/03/01-2013/02/28