Creation of oxygen reduction reaction active sites on titanium oxynitride without increasing the nitrogen doping level

Abstract

The oxygen reduction reaction (ORR) active sites on titanium oxynitride (TiO_xN_y) have been investigated using catalysts with various nitrogen doping levels, leaving some margins to determine their origin. Herein, low-temperature annealing enhanced the ORR activity of carbon-support-free TiO_xN_y with a constant nitrogen doping level, indicating that oxygen vacancies produced the sites.