4 October, 2011

Social Outreach Seminar: Producing Hydrogen
via Solar Energy-Driven Water Splitting―On the road to making practical use of hydrogen,the ultimate clean renewable energy resource―
School of Engineering, The University of Tokyo
The KAITEKI Institute, Inc.
Mitsubishi Chemical Group Science and Technology Research Center, Inc.
INPEX CORPORATION

School of Engineering, The University of Tokyo (Bunkyo-ku, Tokyo; Dean: TakehikoKitamori), The KAITEKI Institute (head office: Minato-ku, Tokyo; President: Yoshimitsu
Kobayashi), Mitsubishi Chemical Group Science and Technology Research Center(head office: Yokohama, Kanagawa Prefecture; President: Kizo Shibata), and INPEXCORPORATION (head office: Minato-ku, Tokyo; President: Toshiaki Kitamura) haveestablished a Social Outreach Seminar “The Chemical Process of Solar Energy
Conversion”, which focuses on the development of a hydrogen production process
utilizing solar power-driven water splitting. The Seminar will be carried out over threeyears, starting in August 2011.
In recent years, with problems of energy and natural resources become more
serious, the importance of forward progress in the development of renewable, cleansources of energy, has grown substantially.
Hydrogen is seen as holding tremendous promise as the ultimate renewable energy
resource. This is due to the fact that when hydrogen combusts, all that is produced
and left behind is water, making it an exceedingly clean source of energy. As well, in
its reactions with carbon dioxide gas (a chief contributor to global warming), it ispossible to create hydrocarbon fuels and other chemical materials.
However, under the current circumstances, most hydrogen is being produced byusing non-renewable resources, such as methane and petroleum. While a method
using electrolysis powered by electricity collected in solar batteries is thought to befeasible, the cost is high from a practical application perspective.
As such, innovative production methods which would allow for the direct generationof hydrogen through solar energy-driven water splitting have a significant amount ofappeal.
The School of Engineering, The University of Tokyo, has been seeking a method toproduce hydrogen directly using solar power, joint research with The KAITEKI Instituteand Mitsubishi Chemical Group Science and Technology Research Center. At thistime, INPEX CORPORATION, Japan’s largest oil and gas exploration and production(E&P) company with operations spanning 26 countries around the world, has now
participated in establishing this Seminar.
With regard to the hydrogen generation via water splitting using photocatalysis, anextremely high degree of efficiency is thought to be realizable in the case of using only
ultraviolet light which is contained in the sun’s rays. In the case of using the sunlightin its entirety, however, numerous challenges lie ahead in increasing its production
efficiency.
To meet such challenges, it is understood to collect comprehensively the wide rangeof knowledge such as those regarding electronic properties of solids, catalysis science,
inorganic and organic synthetic chemistry, the physical properties of fluids, processsynthesis, and chemical engineering.
Professor Kazunari Domen, School of Engineering, the University of Tokyo, who is apioneer of this field, will operate the Seminar to advance the world’s most cutting-edge
research to develop a hydrogen generation process driven by water split using solar
photocatalysis.
The KAITEKI Institute, Mitsubishi Chemical Group Science and Technology
Research Center, and INPEX CORPORATION are viewing the hydrogen production
process, driven by water splitting using solar photocatalysis, with a great deal ofpromise as a mid- to long-range renewable energy and natural resources production.
In evaluating the economic viability of this process, the perspective of industry is also
reflected in this initiative, which further contributes to the acceleration of researchprogress.

Diagram: Generating hydrogen with water splitting using solar photocatalysis

A photocatalyst is composed of an optical semiconductor, represented here by thelarge sphere, and a number of cocatalysts, which are shown resting on said large
sphere.
In taking in sunlight, an electron hole (h+) and an electron (e-) are generated. Theelectron hole oxidizes the water, and oxygen (O 2 ) is formed. As well, the proton H+
which was formed simultaneously will react with the aforementioned electron e- on thecocatalyst, and form hydrogen H 2 .
Open Seminar Outline(1) Lecture Name: Seminar on the Chemical Process of Solar Energy Conversion(2) Location: School of Engineering, The University of Tokyo(3) Lecture Period: Three years, commencing in August 2011
(4) Research Partners:
The KAITEKI Institute, Inc.
(100% subsidiary of Mitsubishi Chemical Holdings Group. An RD think tankconducting research and surveys focused on long-term issues, spanning 20-50years from now.)
Mitsubishi Chemical Group Science and Technology Research Center, Inc.
（The RD arm of Mitsubishi Chemical Holdings Group.）
INPEX CORPORATION（Japan’s largest oil and gas exploration and production (E&P) company withoperations spanning 26 countries around the world.）(5) Instructors: Kazunari Domen (Professor), Masao Katayama (Assistant Professor),
Tsutomu Minegishi (Assistant Professor)(6) Research Goal: To develop the relevant materials and process for realizing
effective utilization of solar and hydrogen energy.

“Social Outreach Seminars” are lectures carried out at The University of Tokyo
faculties or research groups, which receive funding from business corporations
looking to participate in joint research efforts, whose objectives reap significant
benefits to the public good.

For inquiries regarding this bulletin
Tatsuya Okubo, Professor, Social Outreach Seminar Steering Committee Chair
School of Engineering, The University of Tokyo
Tel: 03-5841-7348
The KAITEKI Institute, Inc.
General Planning OfficeAtsuo Takeuchi
Tel: 03-6414-4258
INPEX CORPORATION
Public Relations Group
Tel: 03-5572-0233