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Response of a Model of CO Oxidation with CO Desorption and Diffusion to a Periodic External CO Pressure

G. M. Buendia·E. Machado·P. A. Rikvold
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Abstract

We present a study of the dynamical behavior of a Ziff-Gulari-Barshad model with CO desorption and lateral diffusion. Depending on the values of the desorption and diffusion parameters, the system presents a discontinuous phase transition between low and high CO coverage phases. We calculate several points on the coexistence curve between these phases. Inclusion of the diffusion term produces a significant increase in the CO_2 production rate. We further applied a square-wave periodic pressure variation of the partial CO pressure with parameters that can be tuned to modify the catalytic activity. Contrary to the diffusion-free case, this driven system does not present a further enhancement of the catalytic activity, beyond the increase induced by the diffusion under constant CO pressure.

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G. M. Buendia, E. Machado, P. A. Rikvold. 2006-03-20. Response of a Model of CO Oxidation with CO Desorption and Diffusion to a Periodic External CO Pressure. https://doi.org/10.1016/j.theochem.2006.01.039

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