Active sites for tandem reactions of CO reduction and ethane dehydrogenation.

Ethylene (CH) is one of the most important raw materials for chemical industry. The tandem reactions of CO-assisted dehydrogenation of ethane (CH) to ethylene creates an opportunity to effectively use the underutilized ethane from shale gas while mitigating anthropogenic CO emissions. Here we identify the most likely active sites over CeO-supported NiFe catalysts by using combined in situ characterization with density-functional theory (DFT) calculations. The experimental and theoretical results reveal that the Ni-FeO interfacial sites can selectively break the C-H bonds and preserve the C-C bond of CH to produce ethylene, while the Ni-CeO interfacial sites efficiently cleave all of the C-H and C-C bonds to produce synthesis gas. Controlled synthesis of the two distinct active sites enables rational enhancement of the ethylene selectivity for the CO-assisted dehydrogenation of ethane.