Selective reduction of carbon dioxide to carbon monoxide over Au/CeO2 catalyst and identification of reaction intermediate

CO2 selective reduction to CO with H-2 over a CeO2-supported nano-Au catalyst at atmospheric pressure was investigated. A high CO2 conversion, approaching the thermodynamic equilibrium value, and nearly 100% CO selectivity were obtained. The surface formate intermediates generated during the reverse water-gas shift reaction at 400 degrees C were identified using in situ diffuse-reflectance infrared Fourier-transform spectroscopy. The formate consumption to give CO and H2O, determined using mass spectrometry, indicated that the reaction proceeded via an associative formate mechanism; this contributes to the high Au/CeO2 catalytic activity at low temperatures. (C) 2016, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.