Theoretical study for the reduction of N₂O with CO Mediated by alkaline-earth metal oxide cations ²MO⁺(M=Ca, Sr, Ba)

The reaction mechanism of the reaction N₂O(⁰Σ⁺) + CO (¹Σ⁺)→N₂ (¹Σ_g⁺) + CO₂ (¹Σ_g⁺) mediated by alkaline-earth metal oxide cations ²MO⁺ (m=Ca, Sr, Ba) have been investigated by using the UB3LYP and CCSD (T) levels of theory. The O-atom affinities (OA) testified that only the ²CaO⁺ can capture O from N₂O and transfer O to CO is thermodynamically allowed in three ions. The processes can be expressed as channels l and 2 for the reaction of N₂O and CO mediated by ²MO⁺ (M=Ca, Sr, Ba). For the former, the main reaction processes in a two-step manner to products, the ²MO⁺, as a catalyzer, transports an oxygen atom from N₂O to CO. For the latter, firstly, the N₂O interact with the ²MO⁺ to form IM1, then IM1 interact with the CO to form IM2', along the reaction pathway the intermediate species convert into products ²1MO⁺, N₂ and CO₂. From above results, the following conclusion was drawn. The channel 2 is kinetically and thermodynamically feasible. Our calculated results show the title reactions are accord with the experiment. (authors)