Understanding of dynamic structure of active sites is of paramounti mportance for rational design of industrialc atalysts. This work revealed the structure evolution of iron active phases for CO 2 hydrogenation over iron-based catalysts. With a combination of operando Ramans pectroscopy and X-ray Diffraction coupled with online gas chromatography,t he panoramic structure evolution of iron oxides (a-Fe 2 O 3 and g-Fe 2 O 3 ) during activation and CO 2 hydrogenation were elaborated, that is, a-
CeO 2 nanorods supported Co−CoO x catalysts showed high selectivity for higher alcohol synthesis (HAS) from syngas. The selectivity has found to increase with lowering the Co loadings, and the value over Co 1 /CeO 2 (19.86%) is twice higher than that over Co 5 /CeO 2 (8.67%).The active sites at the interfaces between Co 0 and CoO x , or to say, Co−CoO x pairs, have evidenced to be responsible for HAS. The strong metal−support interactions between Co and CeO 2 retard the reduction of CoO x and stabilize the intermediates such as CO−Co δ+ . Likely, CO favors dissociating on the metallic Co surface to form CH x species, while CO is associatively activated on Co δ+ sites. Moreover, the structure evolution of the Co−CoO x interface was revealed during calcination, reduction, and reaction using in situ X-ray diffraction (XRD), in situ Raman spectroscopy, X-ray absorption spectroscopy (XAS), and in situ diffuse reflectance infrared fourier transform spectroscopy (CO-DRIFTS). The structure−performance relationship of HAS over Co/CeO 2 was proposed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.