Nippon Telegraph and Telephone Corporation

Yuya Uzumaki

Takeshi Komatsu

Yoko Ono

Sayumi Sato

Masahiko Hayashi

Masaya Nohara

Mikayo Iwata

Shuhei Sakamoto

Akihiro Kono

A gas phase reduction device for carbon dioxide is a gas phase reduction device for carbon dioxide that exerts a catalytic function by light irradiation to generate oxidation-reduction reaction. The gas phase reduction device includes an oxidation tank in which an aqueous solution is put, a reduction tank to which carbon dioxide is supplied, a semiconductor photoelectrode installed in the aqueous solution, and a porous electrode-supported electrolyte membrane that is a joint body of an electrolyte membrane and a porous reduction electrode, the porous electrode-supported electrolyte membrane being installed between the oxidation tank and the reduction tank with the electrolyte membrane facing the oxidation tank and the porous reduction electrode facing the reduction tank. Voltage between a reference electrode installed in the aqueous solution and a reference electrode installed in contact with the electrolyte membrane is measured by a voltmeter, and a control unit increases voltage between the semiconductor photoelectrode and the porous reduction electrode in accordance with change in voltage between the reference electrodes from an initial value at start of reaction. The control unit includes a solar cell and a constant voltage power supply, and the solar cell is arranged on an extension line of a straight line from a light source toward the semiconductor photoelectrode, and generates power utilizing light emitted to and transmitted through the semiconductor photoelectrode.

Carbon dioxide gas-phase reduction device and carbon dioxide gas-phase reduction method

Provided is a method for producing a nitride semiconductor photoelectrode capable of improving the light energy conversion efficiency. The method for producing a nitride semiconductor photoelectrode includes a first step of forming an n-type gallium nitride layer on an insulating or conductive substrate, a second step of forming an indium gallium nitride layer on the n-type gallium nitride layer, a third step of forming a nickel layer n the indium gallium nitride layer, and a fourth step of heat-treating the nickel layer in an oxygen atmosphere.

Method for producing nitride semiconductor photoelectrode

Improvement in the efficiency of carbon dioxide reduction reaction is achieved. A gas supply unit having a plurality of pores is established in a lower portion of a reduction chamber, and carbon dioxide is supplied as bubbles into an aqueous solution. This can elevate a concentration of carbon dioxide dissolved in the aqueous solution without stirring the aqueous solution using a stirring bar, and render the concentration uniform in the aqueous solution. Therefore, the efficiency of reduction reaction of carbon dioxide in a reduction electrode can be improved.

Carbon dioxide reduction device

The sheet mask includes multiple battery parts arranged such that electric currents flow along mimic muscles or flows of lymph. This allows an active ingredient to penetrate into in-body tissues more effectively and also allows the mimic muscles and the lymphatic vessels to be electrically stimulated. Forming the battery parts by using materials with low environmental load allows easy disposal of the sheet mask in everyday life.

Sheet mask comprising a battery part

To improve the efficiency of a reduction reaction. A power source applies a voltage to an oxidation electrode immersed in an aqueous solution in an oxidation tank and a reduction electrode immersed in an aqueous solution in a reduction tank, the voltage having a voltage value that changes with a predetermined cycle to be a voltage value at which ions can be desorbed from a surface of the oxidation electrode and a surface of the reduction electrode during one cycle of the voltage change. The frequency of the voltage is set within a range of 10 Hz to 1 kHz.

Growing community of inventors

Musashino, Japan

Yuya Uzumaki