Operando computational catalysis – realistic structures, shapes and coverages
The structure and coverage of catalysts under reaction conditions often differs dramatically from the ideal models often used in computational catalysis. By incorporating effects of pressure and temperature in our simulations, we describe how ideal surfaces undergo a massive reconstruction to form active sites under reaction conditions, and how some particles change shape, while others don’t. In combination with operando microscopy, the dynamics of catalyst systems is finally revealed.
While catalyst surfaces are often highly covered by reactants and reaction intermediates, many computational models still use ideal clean surfaces. For Fischer-Tropsch synthesis and for ketone hydrogenation, we find that coverage effects change both the activity and the selectivity of the kinetic model and are hence critical ingredients in next generation computational models.