Fig. 5: DFT calculations for the reaction pathway of SCR over dimeric and monomeric vanadia.

The optimized molecular structures for the reactant, transition states, intermediates, product, and reaction energies were determined using DFT theory for each elementary step in the NH3-SCR mechanism over the surfaces of (a) dimeric surface vanadia site and (b) monomeric surface vanadia site. Red, cyan, green, blue, and white circles denote O, Ti, V, N, and H atoms, respectively.