Patents by Inventor Akimitsu Ishihara
Akimitsu Ishihara has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 12142769Abstract: Provided is a novel oxygen reduction catalyst having good stability and higher oxygen reduction performance. The oxygen reduction catalyst includes a composite oxide comprising a conductive tin oxide containing Zr.Type: GrantFiled: June 9, 2020Date of Patent: November 12, 2024Assignee: NATIONAL UNIVERSITY CORPORATION YOKOHAMA NATIONAL UNIVERSITYInventors: Akimitsu Ishihara, Takaaki Nagai
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Publication number: 20220255087Abstract: Provided is a novel oxygen reduction catalyst having good stability and higher oxygen reduction performance. The oxygen reduction catalyst includes a composite oxide comprising a conductive tin oxide containing Zr.Type: ApplicationFiled: June 9, 2020Publication date: August 11, 2022Applicant: NATIONAL UNIVERSITY CORPORATION YOKOHAMA NATIONAL UNIVERSITYInventors: Akimitsu ISHIHARA, Takaaki NAGAI
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Publication number: 20200406241Abstract: An object of the invention is to provide an oxygen reduction catalyst composed of a titanium oxynitride having high oxygen reduction capacity. The oxygen reduction catalyst of the invention is a titanium oxynitride that has a nitrogen element content of 0.1 to 2.0 mass %, has a crystal structure of rutile titanium dioxide in a powder X-ray diffraction measurement, and has a signal intensity ratio N—Ti—N/O—Ti—N in an X-ray photoelectron spectroscopic analysis of in the range of 0.01 to 0.50. Further, the oxygen reduction catalyst of the invention is a titanium oxynitride that includes titanium oxide particles, has a crystal structure of rutile titanium dioxide, and has an amorphous layer in a surface layer of the titanium oxide particles.Type: ApplicationFiled: December 22, 2017Publication date: December 31, 2020Applicants: SHOWA DENKO K.K., NATIONAL UNIVERSITY CORPORATION YOKOHAMA NATIONAL UNIVERSITYInventors: Kunchan LEE, Yoshinori YAMATO, Kenichiro OTA, Akimitsu ISHIHARA
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Patent number: 10658676Abstract: An object of the invention is to provide an oxygen reduction catalyst composed of a titanium oxynitride having high oxygen reduction capacity. The oxygen reduction catalyst of the invention is a titanium oxynitride that has a nitrogen element content of 8.0 to 15 mass %, has a crystal structure of anatase titanium dioxide in a powder X-ray diffraction measurement, and has a signal intensity ratio N—Ti—N/O—Ti—N in an X-ray photoelectron spectroscopic analysis of in the range of 0.35 to 0.70.Type: GrantFiled: December 22, 2017Date of Patent: May 19, 2020Assignees: SHOWA DENKO K.K., NATIONAL UNIVERSITY CORPORATION YOKOHAMA NATIONAL UNIVERSITYInventors: Kunchan Lee, Yoshinori Yamato, Kenichiro Ota, Akimitsu Ishihara
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Publication number: 20190386319Abstract: An object of the invention is to provide an oxygen reduction catalyst composed of a titanium oxynitride having high oxygen reduction capacity. The oxygen reduction catalyst of the invention is a titanium oxynitride that has a nitrogen element content of 8.0 to 15 mass %, has a crystal structure of anatase titanium dioxide in a powder X-ray diffraction measurement, and has a signal intensity ratio N—Ti—N/O—Ti—N in an X-ray photoelectron spectroscopic analysis of in the range of 0.35 to 0.70.Type: ApplicationFiled: December 22, 2017Publication date: December 19, 2019Applicants: SHOWA DENKO K.K., NATIONAL UNIVERSITY CORPORATION YOKOHAMA NATIONAL UNIVERSITYInventors: Kunchan LEE, Yoshinori YAMATO, Kenichiro OTA, Akimitsu ISHIHARA
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Patent number: 10050282Abstract: The present invention provides a novel oxygen reduction catalyst having a good stability and a high oxygen reduction performance. The oxygen reduction catalyst includes: a conductive oxide; and an oxide(s), having oxygen holes and provided at least on the surface of the conductive oxide, of at least one or more transition metals selected from the group consisting of Ti, Zr, Nb and Ta.Type: GrantFiled: February 27, 2015Date of Patent: August 14, 2018Assignee: National University Corporation Yokohama National UniversityInventors: Kenichiro Ota, Akimitsu Ishihara, Shigenori Mitsushima, Makoto Hamazaki
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Patent number: 9630169Abstract: A semiconductor material of the present invention is a semiconductor material including an oxynitride containing at least one element selected from the Group 4 elements and Group 5 elements. In the oxynitride, part of at least one selected from oxygen and nitrogen is substituted with carbon. Nb is preferable as the Group 5 element.Type: GrantFiled: August 31, 2012Date of Patent: April 25, 2017Assignee: PANASONIC CORPORATIONInventors: Kazuhito Hato, Kenichi Tokuhiro, Takahiro Suzuki, Takaiki Nomura, Kenichiro Ota, Akimitsu Ishihara
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Publication number: 20170098830Abstract: The present invention provides a novel oxygen reduction catalyst having a good stability and a high oxygen reduction performance. The oxygen reduction catalyst includes: a conductive oxide; and an oxide(s), having oxygen holes and provided at least on the surface of the conductive oxide, of at least one or more transition metals selected from the group consisting of Ti, Zr, Nb and Ta.Type: ApplicationFiled: February 27, 2015Publication date: April 6, 2017Applicant: National University Corporation Yokohama National UniversityInventors: Kenichiro Ota, Akimitsu Ishihara, Shigenori Mitsushima, Makoto Hamazaki
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Publication number: 20140224665Abstract: A semiconductor material of the present invention is a semiconductor material including an oxynitride containing at least one element selected from the Group 4 elements and Group 5 elements. In the oxynitride, part of at least one selected from oxygen and nitrogen is substituted with carbon. Nb is preferable as the Group 5 element.Type: ApplicationFiled: August 31, 2012Publication date: August 14, 2014Applicant: PANASONIC CORPORATIONInventors: Kazuhito Hato, Kenichi Tokuhiro, Takahiro Suzuki, Takaiki Nomura, Kenichiro Ota, Akimitsu Ishihara
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Patent number: 7919427Abstract: A catalyst carrier, being characterized in that a catalyst metal for promoting an oxidation-reduction reaction is carried on a vapor-grown carbon fiber having an average outer diameter of from 2 nm to 500 nm, which has been subjected to a crushing treatment so as to have a BET specific surface area of from 4 m2/g to 100 m2/g and an aspect ratio of from 1 to 200, and exhibiting high activity per unit amount of a catalyst metal, a low reaction resistance and an improved output density, and is useful for a fuel cell; a production method thereof and a fuel cell using the catalyst carrier.Type: GrantFiled: April 28, 2010Date of Patent: April 5, 2011Assignee: Showa Denko K.K.Inventors: Ken-ichiro Ota, Akimitsu Ishihara, Satoshi Iinou, Akinori Sudoh
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Patent number: 7919215Abstract: A corrosion-resistant electrode catalyst for oxygen reduction includes a main catalyst composed of at least one transition metal oxide selected from oxygen-deficient ZrO2, Ta2O5, Nb2O5, TiO2, V2O5, MoO3, and WO3 and a co-catalyst composed of gold. The electrode catalyst is used in contact with an acidic electrolyte at a potential at least 0.4 V higher than the reversible hydrogen electrode potential. The catalyst may be used, for example, in such a form that the transition metal oxide in the form of fine particles and gold in the form of fine particles, or fine particles including fine gold particles coated with the transition metal oxide are dispersed on a catalyst carrier which is an electron conductive powder. This electrode catalyst is suitable as an electrode catalyst for an electrochemical system using an acidic electrolyte in the fields of water electrolysis, inorganic/organic electrolysis, fuel cells, etc.Type: GrantFiled: August 18, 2005Date of Patent: April 5, 2011Assignee: Japan Science and Technology AgencyInventors: Kenichiro Ota, Nobuyuki Kamiya, Shigenori Mitsushima, Akimitsu Ishihara, Liu Yan
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Publication number: 20100279202Abstract: An electrode catalyst for an oxygen reduction electrode for use in a cathode of a polymer electrolyte fuel cell, produced by oxidizing ZrCN, wherein ZrCN and ZrO2 are detected by X-ray diffraction of the electrode catalyst, the electrode catalyst has an ionization potential of 5.0 to 6.0 eV, and ZrO2 is detected by X-ray photoelectron spectroscopy of the electrode catalyst.Type: ApplicationFiled: October 30, 2008Publication date: November 4, 2010Inventors: Ken-ichiro Ota, Shigenori Mitsushima, Akimitsu Ishihara, Yoshiro Ohgi
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Publication number: 20100216057Abstract: A catalyst carrier, being characterized in that a catalyst metal for promoting an oxidation-reduction reaction is carried on a vapor-grown carbon fiber having an average outer diameter of from 2 nm to 500 nm, which has been subjected to a crushing treatment so as to have a BET specific surface area of from 4 m2/g to 100 m2/g and an aspect ratio of from 1 to 200, and exhibiting high activity per unit amount of a catalyst metal, a low reaction resistance and an improved output density, and is useful for a fuel cell; a production method thereof and a fuel cell using the catalyst carrier.Type: ApplicationFiled: April 28, 2010Publication date: August 26, 2010Applicant: SHOWA DENKO K.K.Inventors: Ken-ichiro OTA, Akimitsu ISHIHARA, Satoshi IINOU, Akinori SUDOH
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Patent number: 7749935Abstract: A catalyst carrier, being characterized in that a catalyst metal for promoting an oxidation-reduction reaction is carried on a vapor-grown carbon fiber having an average outer diameter of from 2 nm to 500 nm, which has been subjected to a crushing treatment so as to have a BET specific surface area of from 4 m2/g to 100 m2/g and an aspect ratio of from 1 to 200, and exhibiting high activity per unit amount of a catalyst metal, a low reaction resistance and an improved output density, and is useful for a fuel cell; a production method thereof and a fuel cell using the catalyst carrier.Type: GrantFiled: January 26, 2005Date of Patent: July 6, 2010Assignee: Showa Denko K.K.Inventors: Ken-ichiro Ota, Akimitsu Ishihara, Satoshi Iinou, Akinori Sudoh
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Patent number: 7670712Abstract: An electrode catalyst that maintains catalytic activity under conditions of an electrode potential as high as 0.4 V or above and exhibits improved stability. The metal oxynitride electrode catalyst is composed of an oxynitride containing at least one transition metal element selected from the group consisting of La, Ta, Nb, Ti, and Zr, the metal oxynitride electrode catalyst being used at a potential of 0.4 V or higher relative to the reversible hydrogen electrode potential in an acidic electrolyte. The metal oxynitride electrode catalyst is useful as an electrode catalyst for electrochemical systems used in acidic electrolytes in the fields of water electrolysis, organic electrolysis, fuel cells, etc.Type: GrantFiled: November 30, 2004Date of Patent: March 2, 2010Assignee: Japan Science and Technology AgencyInventors: Kenichiro Ota, Nobuyuki Kamiya, Shigenori Mitsushima, Akimitsu Ishihara, Kazunari Doumen, Michikazu Hara
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Publication number: 20070259267Abstract: A corrosion-resistant electrode catalyst for oxygen reduction includes a main catalyst composed of at least one transition metal oxide selected from oxygen-deficient ZrO2, Ta2O5, Nb2O5, TiO2, V2O5, MoO3, and WO3 and a co-catalyst composed of gold. The electrode catalyst is used in contact with an acidic electrolyte at a potential at least 0.4 V higher than the reversible hydrogen electrode potential. The catalyst may be used, for example, in such a form that the transition metal oxide in the form of fine particles and gold in the form of fine particles, or fine particles including fine gold particles coated with the transition metal oxide are dispersed on a catalyst carrier which is an electron conductive powder. This electrode catalyst is suitable as an electrode catalyst for an electrochemical system using an acidic electrolyte in the fields of water electrolysis, inorganic/organic electrolysis, fuel cells, etc.Type: ApplicationFiled: August 18, 2005Publication date: November 8, 2007Applicant: JAPAN SCIENCE AND TECHNOLOGY AGENCYInventors: Kenichiro Ota, Nobuyuki Kamiya, Shigenori Mitsushima, Akimitsu Ishihara, Liu Yan
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Publication number: 20070128884Abstract: [Problems] Carbides and many other non-platinum-based compounds are activated and dissolved and cannot be stably present in an acidic electrolyte under conditions of an electrode potential as high as 0.4 V or above, and thus, the application range of these compounds as an electrode catalyst is limited to low electrode potentials. There has been need for development of an electrode catalyst that maintains catalytic activity under these conditions and exhibits improved stability. [Means for Solving Problems] To provide a metal oxynitride electrode catalyst composed of an oxynitride containing at least one transition metal element selected from the group consisting of La, Ta, Nb, Ti, and Zr, the metal oxynitride electrode catalyst being used at a potential of 0.4 V or higher relative to the reversible hydrogen electrode potential in an acidic electrolyte.Type: ApplicationFiled: November 30, 2004Publication date: June 7, 2007Applicant: JAPAN SCIENCE AND TECHNOLOGY AGENCYInventors: Kenichiro Ota, Nobuyuki Kamiya, Shigenori Mitsushima, Akimitsu Ishihara, Kazunari Doumen, Michikazu Hara
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Publication number: 20050245390Abstract: A catalyst carrier, being characterized in that a catalyst metal for promoting an oxidation-reduction reaction is carried on a vapor-grown carbon fiber having an average outer diameter of from 2 nm to 500 nm, which has been subjected to a crushing treatment so as to have a BET specific surface area of from 4 m2/g to 100 m2/g and an aspect ratio of from 1 to 200, and exhibiting high activity per unit amount of a catalyst metal, a low reaction resistance and an improved output density, and is useful for a fuel battery; a production method thereof and a fuel battery using the catalyst carrier.Type: ApplicationFiled: January 26, 2005Publication date: November 3, 2005Applicant: SHOWA DENKO K.K.Inventors: Ken-ichiro Ota, Akimitsu ishihara, Satoshi Iinou, Akinori Sudoh