The effects of support morphology on the performance of Pt/CeO2 catalysts for the low temperature steam reforming of ethanol

Abstract A series of Pt/CeO2 catalysts with different support morphologies was studied for the low temperature ethanol steam reforming. Different ceria nanostructures (nanocube_NC, nanorod_NR and flower-like_FL) were prepared by the hydrothermal method and are compared with CeO2 obtained by precipitation. Support morphology was found to influence certain reaction routes, even though the reaction scheme was the same regardless of the support. Concerning catalyst stability at 573 K, Pt/CeO2- PPT exhibited rapid deactivation, whereas Pt/CeO2- NR remained rather stable. XPS surface analysis before and after reaction at 573 K revealed significant degree of Pt reduction on CeO2 nanorods, directly related to the reduction of Ce4+ into Ce3+. DRIFTS experiments under reaction conditions for 5 h, revealed an accumulation of acetates on the Pt/CeO2- PPT catalyst, likely due to the imbalance between the rate of acetate species decomposition to CHx (not facilitated over Ptδ+ of the catalyst with the lower Pt dispersion), and their desorption as CH4.