| abstract |
[PROBLEMS] To provide a catalyst which has both functions of oxygen reduction during discharge and oxygen generation during charge in an air secondary battery, and which is stable even at a high potential during charge. [Measures] A catalyst composed of carbonitride oxide of a specific transition metal selected from titanium, zirconium, hafnium, vanadium, niobium, tantalum, or the like has both functions of reducing oxygen during discharge and generating oxygen during charge in an air secondary battery. It discovered that it was stable also at the high electric potential at the time of charge, and came to complete this invention. |