First‐principles Assessment of the Role of Water in the Reduction Half Cycle of Low‐Temperature NH₃‐SCR over Cu‐CHA

The Front Cover illustrates a tug-of-war played between two concomitant but opposite effects brought forth by the presence of H2O in the Reduction Half-Cycle (RHC) of NH3-SCR, leading to a reduction in both the rate and its apparent activation energy with respect to dry conditions. In their Research Article, M. Maestri, E. Tronconi and co-workers show that such phenomena are a consequence of enthalpic stabilization and additional entropic penalties of the TS brought forth by the presence of H2O in the cage of Cu-CHA. This result thus provides a theoretical understanding of the kinetic role of H2O in the RHC, highlighting the importance of the molecular scale description of the reaction environment in voids of molecular dimensions. Image credit: Gabriele Contaldo and Lia Tagliavini. More information can be found in the Research Article by M. Maestri, E. Tronconi and co-workers.