The University of Tokyo

Riken Corporation

Japan Science and Technology Agency

Tosoh Corporation

Japan Agency for Marine-earth Science and Technology

Ryuhei Nakamura

Kazuhito Hashimoto

Akira Yamaguchi

Soichiro Kato

Toru Hayashi

Kazumasa Suetsugu

Shuhei Miura

Hiroshi Irie

Ikuo Sawada

Tomokazu Saruhashi

Ken Takai

Kentaro Nakamura

Takazo Shibuya

Junichi Miyazaki

Hirotaka Kakizaki

Masahiro Yamamoto

Fumiyoshi Kai

Kazuya Watanabe

Hideshi Ooka

Nadege Bonnet

Ailong Li

Shuang Kong

Hongxian Han

To provide a manganese-iridium composite oxide, a manganese-iridium composite oxide and a manganese-iridium composite oxide electrode material, having high catalytic activity produced at low cost, to be used as an anode catalyst for oxygen evolution in water electrolysis, and their production methods. A manganese-iridium composite oxide, which has an iridium metal content ratio (iridium/(manganese+iridium)) of 0.1 atomic % or more and 30 atomic % or less, and has interplanar spacings of at least 0.243±0.002 nm, 0.214±0.002 nm, 0.165±0.002 nm, 0.140±0.002 nm, and a manganese-iridium composite oxide electrode material comprising an electrically conductive substrate constituted by fibers at least part of which are covered with the above manganese-iridium composite oxide.

Manganese-iridium composite oxide for water splitting catalyst, manganese-iridium composite oxide electrode material, and their production methods

The present invention provides a water electrolysis method comprising: supplying at least water into an electrolysis cell which includes a solid polymer electrolyte membrane, and an anode and a cathode disposed sandwiching the solid polymer electrolyte membrane therebetween; and providing a potential P between the anode and the cathode to generate oxygen from the anode, wherein an oxidation catalyst containing at least one of first transition metals is present on at least a part of a surface of the anode, and the potential P satisfies P&#x3c;P&#x3c;P, wherein Pindicates a lowest potential at which oxygen is generated from the anode, and Pindicates a lowest potential Pat which a quantitative index of a dissolved chemical species derived from the oxidation catalyst begins to show potential dependence.

Method and apparatus for water electrolysis, and method for determining drive potential of water electrolysis

Provided is a catalyst that exhibits a high catalyst activity in a water oxidation reaction within a neutral range. A water splitting catalyst comprises at least one 3d-block transition metal element selected from manganese, iron, cobalt, nickel, and copper or a compound containing the element, and a base and/or a carbonate having a pKa of 8 or less.

Water splitting catalyst, and method for producing oxygen and hydrogen using the same

A power generation system includes a hydrothermal fluid well including a drilled hole reaching down to a hydrothermal fluid reservoir present below an ocean floor from an ocean floor surface and a casing installed in the drilled hole through a guide base on the ocean floor surface, an anode provided on a flow channel for hot water formed by the hydrothermal fluid well, a cathode provided in seawater other than the flow channel for hot water formed by the hydrothermal fluid well, and an ocean floor device that is connected with the anode and the cathode respectively and extracts generated power so as to operate. Power is easily and stably supplied on the ocean floor.

Power generation system

It is an object of the present invention to provide a microbial fuel cell capable of increasing a current density without employing a mediator. The microbial fuel cellincludes a 3-dimensionally structured agglomerate formed from conductive fine particlesand microorganisms. In the agglomerate, the conductive fine particlesdisperse among pieces ofand the conductive fine particlesare coupled to one another to hold, thus forming the 3-dimensional structure as a whole. Accordingly, with respect to, conductive fine particlesholdon a surface of an electrodeand evenpositioned vertically away from the surface of the electrode. Hence, it becomes possible that more pieces ofare allowed to transfer electrons.

Microbial fuel cell

This invention provides a photocatalyst material, which can be produced at low cost without using platinum, particularly a visible light response-type photocatalyst material, a material having a photocatalyst mechanism not possessed by the conventional photocatalyst material, a process for producing the material, and a method for decomposing a contaminant using the material. The photocatalyst material comprises a) an oxide of a first metal and b) an aqua complex salt of a second metal. In this case, for the oxide of a first metal, the redox potential of a conduction band lower end in the oxide is on a rather negative side than 0.2 V (a value as measured at pH=0, vs. reference electrode potential). For the aqua complex salt of a second metal, the redox potential of a second metal ion in the aqua complex salt is on a rather negative side than 3.0 V (a value as measured at pH=0, vs. reference electrode potential). In the material, the aqua complex salt of a second metal is chemically adsorbed on the oxide of a first metal.

Photocatalyst material, process for producing the photocatalyst material, and method for decomposing contaminant using the material

Growing community of inventors

Wako, Japan

Ryuhei Nakamura