%0 Journal Article
%T Operando NAP-XPS unveils differences in MoO3 and Mo2C during hydrodeoxygenation
%J -
%D 2018
%R https://doi.org/10.1038/s41929-018-0171-9
%X MoO3 and Mo2C have emerged as remarkable catalysts for the selective hydrodeoxygenation (HDO) of a wide range of oxygenates at low temperatures (that is, ¡Ü673£¿K) and H2 pressures (that is, ¡Ü1£¿bar). Although both catalysts can selectively cleave C¨CO bonds, the nature of their active sites remains unclear. Here we used operando near-ambient pressure X-ray photoelectron spectroscopy to reveal important differences in the Mo 3d oxidation states between the two catalysts during the hydrodeoxygenation of anisole. This technique revealed that, although both catalysts featured a surface oxycarbidic phase, the oxygen content and the underlying phase of the material impacted the reactivity and product selectivity during the hydrodeoxygenation. MoO3 transitioned between 5+ and 6+ oxidation states during the operation, consistent with an oxygen-vacancy driven mechanism wherein the oxygenate is activated at undercoordinated Mo sites. In contrast, Mo2C showed negligible oxidation state changes during hydrodeoxygenation and maintained mostly 2+ states throughout the reaction
%U https://www.nature.com/articles/s41929-018-0171-9