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Title: Catalytic mechanism and design principle of coordinately unsaturated single metal atom-doped covalent triazine frameworks with high activity and selectivity for CO 2 electroreduction
Electrochemical conversion of carbon dioxide (CO 2 ) to chemicals or fuels can effectively promote carbon capture and utilization, and reduce greenhouse gas emission but a serious impediment to the process is to find highly active electrocatalysts that can selectively produce desired products. Herein, we have established the design principles based on the density functional theory calculations to screen the most promising catalysts from the family of coordinately unsaturated/saturated transition metal (TM) embedded into covalent organic frameworks (TM-COFs). An intrinsic descriptor has been discovered to correlate the molecular structures of the active centers with both the activity and selectivity of the catalysts. Among all the catalysts, the coordinately unsaturated Ni-doped covalent triazine framework (Ni-CTF) is identified as one of the best electrocatalysts with the lowest overpotential (0.34 V) for CO 2 reduction toward CO while inhibiting the formation of the side products, H 2 and formic acid. Compared with coordinately saturated TM-COFs and noble metals ( e.g. Au and Ag), TM-CTFs exhibit higher catalytic activity and stronger inhibition of side products. The predictions are supported by previous experimental results. This study provides an effective strategy and predictive tool for developing desired catalysts with high activity and selectivity.  more » « less
Award ID(s):
1662288
NSF-PAR ID:
10350527
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
9
Issue:
6
ISSN:
2050-7488
Page Range / eLocation ID:
3555 to 3566
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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