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Title: Decoupling Redox Hopping and Catalysis in Metal‐Organic Frameworks ‐based Electrocatalytic CO 2 Reduction
Abstract

Traditional MOF e‐CRR, constructed from catalytic linkers, manifest a kinetic bottleneck during their multi‐electron activation. Decoupling catalysis and charge transport can address such issues. Here, we build two MOF/e‐CRR systems, CoPc@NU‐1000 and TPP(Co)@NU‐1000, by installing cobalt metalated phthalocyanine and tetraphenylporphyrin electrocatalysts within the redox active NU‐1000 MOF. For CoPc@NU‐1000, the e‐CRR responsive CoI/0potential is close to that of NU‐1000 reduction compared to the TPP(Co)@NU‐1000. Efficient charge delivery, defined by a higher diffusion (Dhop=4.1×10−12 cm2 s−1) and low charge‐transport resistance (=59.5 Ω) in CoPC@NU‐1000 led FECO=80 %. In contrast, TPP(Co)@NU‐1000 fared a poor FECO=24 % (Dhop=1.4×10−12 cm2 s−1and=91.4 Ω). For such a decoupling strategy, careful choice of the host framework is critical in pairing up with the underlying electrochemical properties of the catalysts to facilitate the charge delivery for its activation.

 
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Award ID(s):
1944903
NSF-PAR ID:
10413028
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
62
Issue:
22
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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