For the activity of a nano-catalyst, a general and quantitative solution to building direct structure–reactivity relationship has not yet been established. On top of the first principle-based kinetic Monte Carlo (KMC) simulations, we developed a model to build the adsorption site dependence of the activity. We applied this model to study the nano effects of Cu catalysts in the water-gas shift reaction. By accumulating the activities of different adsorption sites, our model satisfactorily reproduced the experimental apparent activation energies for catalysts with sizes over hundreds of nanometers, which were out of reach for conventional KMC simulations. Our results disclosed that, even for a cubic catalyst with size of 877 nm, its activity can still be closely related to the activity of edge sites, instead of only the exposed Cu(100) facets as might have been expected. The present model is expected to be useful for systems that are controlled by the hydrogenation/dehydrogenation processes.

https://onlinelibrary.wiley.com/doi/10.1002/anie.202109942

Scheme 1. Construction of the GCN-activity relationship.