Highly Effective Direct Decomposition of Nitric Oxide by Microwave Catalysis over BaMeO 3 (Me: Mn, Co, Fe) Mixed Oxides at Low Temperature under ExcessOxygen. -BaMO 3 (M: Mn, Co, Fe) mixed oxide NOx decomposition co-catalysts are prepared by sol gel reaction of an aqueous M(NO3)2 solution with citric acid and ethylene glycol is given (80 C) followed by calcination in air (1. 400 C, 2 h, 2. 700 C, 4 h). NO decomposition through microwave catalysis under excess O 2 shows that the BaCoO 3 catalyst has an outstanding activity with a high NO conversion and N2 selectivity of up to 99.8 and 99.9%, resp., even at 250 C. Furthermore, the catalyst shows a superior resistance to H2O vapor. BaMnO3 and BaFeO3 exhibit best NO conversions of 93.7 and only 64.1% under microwave irradiation, respectively. Temperature-programmed H 2 reduction and O2 desorption, as well as microwave-absorbing properties of the mixed oxides are systematically studied in terms of clarifying differences in the catalytic performance. Apparent activation energies of 33.4, 13.7, and 46.7 kJ/mol for BaMnO 3, BaCoO3, and BaFeO3, resp., suggest a significant microwave catalytic effect. -(XU, W.; CAI, J.; ZHOU*, J.; OU, Y.; LONG, W.; YOU, Z.; LUO, Y.; ChemCatChem 8 (2016) 2, 417-425, http://dx.