Abstract
So far, it is still a controversial issue which status of gold species is a better active site for catalyzing CO oxidation. Herein, the influence of the different atmospheres pretreatment (oxidative and reductive) on gold state of Au/La-CeOx (1 wt% gold loading) catalyst during CO oxidation was studied. The changes of Au species were monitored by combined in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) and X-ray photoelectron spectroscopy (XPS). For the sample pretreated with oxidative atmosphere, the data show that the initial Au3+ is transformed to Auδ+ (0 < δ < 1) during CO oxidation, which is a key step to lead to higher reactivity. For the sample after reductive atmosphere pretreatment, Auδ+ is mixed with a small amount of Au0 which can be converted to Auδ+ with the increase of temperature in reaction. Meanwhile, the sample always maintains high activity during the reaction. Therefore, the Auδ+ obtained by reductive pretreatment is more active than the Au3+ obtained by oxidative treatment in catalyzing CO oxidation.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
