Structural changes of the Cu surface of a Cu/ZnO/Al2O3 catalyst, resultingfrom oxidation and reduction, probed by CO infrared spectroscopy

The morphology of the Cu surface of a Cu/ZnO/Al2O3 (60:30:10) catalyst, pro duced by reduction of the copper oxide component of the catalyst either wit h H-2 or CO, has been probed by measuring the IR spectra of CO adsorbed on these surfaces. Pre-reduction in H-2 produces a Cu surface, which contains the (110) and (211) faces and which is active in CO2 decomposition. Re-redu ction of the CO2-oxidised Cu surface in CO results in a twofold increase in the Cu(211) surface. Re-reduction of the CO2-oxidised Cu surface in H-2 re sults in the restoration of the original Cu morphology, i.e. in a decrease in the Cu(211) surface population. Initial reduction of the copper oxide co mponent of the Cu/ZnO/Al2O3 catalyst by CO produces a surface, which is ina ctive in the decomposition of CO2. (C) 2000 Elsevier Science B.V. All right s reserved.