Structural changes of the Cu surface of a Cu/ZnO/Al 2O 3 catalyst, resulting from oxidation and reduction, probed by CO infrared spectroscopy

Abstract

The morphology of the Cu surface of a Cu/ZnO/Al 2O 3 (60:30:10) catalyst, produced by reduction of the copper oxide component of the catalyst either with 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 CO 2 decomposition. Re-reduction of the CO 2-oxidised Cu surface in CO results in a twofold increase in the Cu(211) surface. Re-reduction of the CO 2-oxidised Cu surface in H 2 results 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 component of the Cu/ZnO/Al 2O 3 catalyst by CO produces a surface, which is inactive in the decomposition of CO 2.