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Title: Tuning CO 2 hydrogenation selectivity on Ni/TiO 2 catalysts via sulfur addition
In the context of CO 2 valorization, the possibility of shifting the selectivity of Ni catalysts from CO 2 methanation to reverse water gas shift reaction could be economically attractive provided that the catalyst presents sufficient activity and stability. Remarkably, the addition of sulfur (0.2–0.8% w/w) to nickel on a Ni/TiO 2 catalyst induces a complete shift in the catalyst selectivity for CO 2 hydrogenation at 340 °C from 99.7% CH 4 to 99.7% CO. At an optimal Ni/S atomic ratio of 4.5, the productivity of the catalyst reaches 40.5 mol CO 2 mol Ni −1 h −1 with a good stability. Density functional theory (DFT) calculations performed on various Ni surfaces reveal that the key descriptor of selectivity is the binding energy of the CO intermediate, which is related to the local electron density of surface Ni sites.  more » « less
Award ID(s):
1956403
PAR ID:
10425994
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Catalysis Science & Technology
Volume:
12
Issue:
22
ISSN:
2044-4753
Page Range / eLocation ID:
6856 to 6864
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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