The adsorption/desorption of NO x on commercial Ce x Zr 1− x O 2 solid solutions ( x = 1, 0.85, 0.69, 0.5, 0.21, 0.1, and 0) is reported in this paper. In the first part, the characterization of the ceria-zirconia is carried out by N 2 adsorption at 77 K, TEM, Raman, XRD, and DRIFTS in order to establish relationships between their bulk/surface properties and their NO and NO 2 adsorption/desorption behavior. As deduced from thermogravimetric experiments, the adsorption of NO 2 is promoted in comparison to that of NO with typical surface densities spreading between 3.1−4.6 NO 2 /nm 2 and 1.5−4.5 NO/nm 2 among the Ce x Zr 1− x O 2 series. DRIFTS experiments reveal that NO x adsorption proceeds mainly via electron transfer and/or participation of surface oxygens and OH groups, inducing the formation of negatively charged surface species, such as hyponitrites, nitroxyl anions, nitrites, and nitrates. The mechanistic pathways promoting the formation of the different kinds of ad -NO x species are discussed in function of the catalyst pretreatment, the temperature, the nature of the reactive gas, and the ceria-zirconia composition.
No takes yet. Share an insight, caveat, or question.
Azambre et al. (2009) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: