Delafossite Ag 2 CuMnO 4 is a Novel Catalytic Material for Low‐Temperature Oxidation of CO and NH 3

Ternary oxide of silver, copper, and manganese (Ag 2 CuMnO 4 ) was prepared by hydrothermal synthesis in an alkaline solution. The prepared sample was characterized by a delafossite crystal structure without any other crystallized phases. The catalytic properties of Ag 2 CuMnO 4 in oxidation reactions using molecular oxygen were investigated. High catalytic activity was found for Ag 2 CuMnO 4 in the CO oxidation at room temperature, while ammonia oxidation occurred above 100 °C. Ammonia oxidation resulted in the formation of N 2 O/N 2 or NO/NO 2 products depending on the reaction temperature. As a result of the reaction exposure on Ag 2 CuMnO 4 during heating up to 400 °C, a modification of surface composition with preservation of the delafossite structure was found. Oxide Ag 2 CuMnO 4 was shown to be operating in wet CO oxidation under ambient conditions. Obtained data emphasize that Ag 2 CuMnO 4 can be considered as a novel and prospective catalytic material with a high potential of application for oxidation processes at low temperatures including ambient conditions.