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Title: Dynamic Changes in the Structure, Chemical State and Catalytic Selectivity of Cu Nanocubes during CO 2 Electroreduction: Size and Support Effects
Abstract

In situ and operando spectroscopic and microscopic methods were used to gain insight into the correlation between the structure, chemical state, and reactivity of size‐ and shape‐controlled ligand‐free Cu nanocubes during CO2electroreduction (CO2RR). Dynamic changes in the morphology and composition of Cu cubes supported on carbon were monitored under potential control through electrochemical atomic force microscopy, X‐ray absorption fine‐structure spectroscopy and X‐ray photoelectron spectroscopy. Under reaction conditions, the roughening of the nanocube surface, disappearance of the (100) facets, formation of pores, loss of Cu and reduction of CuOxspecies observed were found to lead to a suppression of the selectivity for multi‐carbon products (i.e. C2H4and ethanol) versus CH4. A comparison with Cu cubes supported on Cu foils revealed an enhanced morphological stability and persistence of CuIspecies under CO2RR in the former samples. Both factors are held responsible for the higher C2/C1product ratio observed for the Cu cubes/Cu as compared to Cu cubes/C. Our findings highlight the importance of the structure of the active nanocatalyst but also its interaction with the underlying substrate in CO2RR selectivity.

 
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NSF-PAR ID:
10067017
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
130
Issue:
21
ISSN:
0044-8249
Page Range / eLocation ID:
p. 6300-6305
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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