Interfacial Sites in Ag Supported Layered Double Oxide for Dehydrogenation Coupling of Ethanol to n-Butanol.

Upgrading of ethanol to n-butanol through dehydrogenation coupling has received increasing attention due to the wide application of n-butanol. But the enhancement of ethanol dehydrogenation and followed coupling to produce high selectivity to n-butanol is still highly desired. Our previous work has reported an acid-base-Ag synergistic catalysis, with Ag particles supported on Mg and Al-containing layered double oxides (Ag/MgAl-LDO). Here, Ag-LDO interfaces have been manipulated for dehydrogenation coupling of ethanol to n-butanol by tailoring the size of Ag particles and the interactions between Ag and LDO. It has been revealed that increasing the population of surface Ag sites at Ag-LDO interfaces promotes not only the dehydrogenation of ethanol to acetaldehyde but also the subsequent aldol condensation of generated acetaldehyde. A selectivity of up to 76 % to n-butanol with an ethanol conversion of 44 % has been achieved on Ag/LDO with abundant interfacial Ag sites, much superior to the state-of-the-art catalysts.