Chemical oscillations in catalytic CO oxidation reaction

Bzovska Bzovska,Mryglod Mryglod

doi:10.5488/cmp.13.34801

Abstract

Temporal dynamics of a heterogeneous catalytic system, namely of the catalytic CO oxidation on Pt(110) surface at low pressures, is investigated with taking into account the adsorbate-driven structural transformations of the catalyst surface. Uniform temporal periodic chemical oscillations of the CO and oxygen coverages, and the fraction of the surface of the 1 × 1 structure are obtained in a narrow region of phase diagram between two uniform stable states of high and low catalytic activities, respectively.

Highlights

Since Langmuir’s pioneering studies, the oxidation of CO over Pt is a classical example of a heterogeneous catalytic reaction
Mathematical modelling of the experiments is conducted using a realistic model of catalytic CO oxidation on Pt(110) first studied by Krischer et al [13]
The difference between model (2)–(3) and the model considered in our earlier paper [7] is that the precursor-type kinetics of CO adsorption is accounted for by the exponent q = 3 in the right hand part of equation (2)

Summary

Introduction

Since Langmuir’s pioneering studies, the oxidation of CO over Pt is a classical example of a heterogeneous catalytic reaction. We will study the more open Pt(110) plane where the oscillatory behavior in the catalytic CO oxidation can be experimentally observed [8, 9]. It is known that in a system, the relaxation oscillations can emerge in bistable state if the system depends on a parameter slowly varying in time.

Results

Conclusion