A generalized “reaction–diffusion” model to describe spatio-temporal patterns in the catalytic CO oxidation on Pt(110)

Abstract

A macroscopic model to describe the spatio-temporal patterns observed in the CO + O₂ reaction on Pt(110) is presented. We consider mass transport in the adsorbed layer as a response to the gradient in chemical potential of adsorbed CO and explicitly take into account the coupling between diffusion and the adsorbate-induced structural transformation of the substrate. Numerical integration of the model equations in two-dimensions revealed target patterns, spiral waves as well as subharmonic standing-wave patterns that closely resemble those observed in experiments. Our results also show that synchronization of the surface can be achieved through nucleation and growth processes even in the absence of gas-phase coupling.