Titanium-Niobium Oxides as Non-Noble Metal Cathodes for Polymer Electrolyte Fuel Cells

Catalysts

Akimitsu Ishihara¹  Yuko Tamura²  Mitsuharu Chisaka⁴  Yoshiro Ohgi³  Yuji Kohno²  Koichi Matsuzawa²  Shigenori Mitsushima¹  Ken-ichiro Ota² 

[1] Institute of Advanced Sciences, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan; E-Mail:;Green Hydrogen Research Center, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan; E-Mails:;Kumamoto Industrial Research Institute, 3-11-38 Azuma-cho, Azuma-ku, Kumamoto, Kumamoto 862-0901, Japan; E-Mail:;Department of Electronics and Information Technology, Hirosaki University, 3 Bunkyo-cho, Hirosaki, Aomori 036-8561, Japan; E-Mail:

关键词: titanium-niobium oxides;    oxygen reduction reaction;    polymer electrolyte fuel cells;    non-platinum cathode;   

DOI  :  10.3390/catal5031289

来源: mdpi

【 摘 要 】

In order to develop noble-metal- and carbon-free cathodes, titanium-niobium oxides were prepared as active materials for oxide-based cathodes and the factors affecting the oxygen reduction reaction (ORR) activity were evaluated. The high concentration sol-gel method was employed to prepare the precursor. Heat treatment in Ar containing 4% H₂ at 700–900 °C was effective for conferring ORR activity to the oxide. Notably, the onset potential for the ORR of the catalyst prepared at 700 °C was approximately 1.0 V vs. RHE, resulting in high quality active sites for the ORR. X-ray (diffraction and photoelectron spectroscopic) analyses and ionization potential measurements suggested that localized electronic energy levels were produced via heat treatment under reductive atmosphere. Adsorption of oxygen molecules on the oxide may be governed by the localized electronic energy levels produced by the valence changes induced by substitutional metal ions and/or oxygen vacancies.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.