From single crystals to working catalysts: integrating in-situ spectroscopy and computational modeling to bridge the pressure gap in ethylene epoxidation

Ethylene oxide (EO) is a vital chemical intermediate produced exclusively via silver-catalyzed epoxidation. A central challenge lies in maximizing selectivity towards EO against competing combustion reactions. This review summarizes recent advancements in understanding the dynamic nature of silver catalysts under working conditions. We highlight the transition from idealized ultra-high vacuum models to working catalysts with in-situ characterization and advanced computational simulations. Key insights include the in-situ identification of active sites under working conditions, the evolution of theoretical approaches from static calculations to machine-learning-driven global optimization and molecular dynamics, facet and size effects, and the mechanistic role of promoters in enhancing selectivity. Future efforts must focus on the integration of in-situ spectroscopy and machine-learning-accelerated simulations to bridge the pressure and materials gaps, paving the way for the rational design of next-generation catalysts.