The electrochemical CO2reduction reaction (CO2RR) to syngas represents a promising solution to mitigate CO2emissions and manufacture value‐added chemicals. Palladium (Pd) has been identified as a potential candidate for syngas production via CO2RR due to its transformation to Pd hydride under CO2RR conditions, however, the pre‐hydridized effect on the catalytic properties of Pd‐based electrocatalysts has not been investigated. Herein, pre‐hydridized Pd nanocubes (PdH0.40) supported on carbon black (PdH0.40NCs/C) are directly prepared from a chemical reduction method. Compared with Pd nanocubes (Pd NCs/C), PdH0.40NCs/C presented an enhanced CO2RR performance due to its less cathodic phase transformation revealed by the in situ X‐ray absorption spectroscopy. Density functional theory calculations revealed different binding energies of key reaction intermediates on PdH0.40NCs/C and Pd NCs/C. Study of the size effect further suggests that NCs of smaller sizes show higher activity due to their more abundant active sites (edge and corner sites) for CO2RR. The pre‐hydridization and reduced NC size together lead to significantly improved activity and selectivity of CO2RR.
- Award ID(s):
- 1808383
- NSF-PAR ID:
- 10100225
- Date Published:
- Journal Name:
- MRS Advances
- Volume:
- 4
- Issue:
- 5-6
- ISSN:
- 2059-8521
- Page Range / eLocation ID:
- 263 to 269
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1557/adv.2019.47
