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  • Selective Electrochemical Reduction of CO 2 to Metal Oxalates in Nonaqueous Solutions Using Trace Metal Pb on Carbon Supports Enhanced by a Tailored Microenvironment
Title: Selective Electrochemical Reduction of CO 2 to Metal Oxalates in Nonaqueous Solutions Using Trace Metal Pb on Carbon Supports Enhanced by a Tailored Microenvironment
Abstract In this work, the electroreduction of carbon dioxide (CO2) to oxalate is enabled by incorporating trace metallic lead (Pb) on carbon‐based supports (CBS) with polymer overlayers. These composite materials serve as an efficient electrocatalytic system for the facile conversion and storage of CO2, a pernicious atmospheric pollutant. Results from controlled potential electrolysis experiments indicate that 1) trace metallic Pb on the ppb scale is active toward the reductive coupling of CO2to oxalate at comparable Faradaic efficiencies to bulk metallic Pb and 2) polymer encapsulation of this trace metallic Pb leads to promotion of CO2reduction (CO2R) selectively to metal oxalates over other products such as CO. Importantly, metal oxalates are important alternative cementitious materials and precursors for other materials’ synthesis applications. The solid products undergo rigorous spectroscopic characterization, including13CO2labeling experiments, to ensure the metal oxalates are in fact produced from CO2R. These findings serve as a model for leveraging microenvironment effects to enhance activity and selectivity for CO2R using trace‐metal catalysts for carbon utilization and storage technologies.  more » « less
Award ID(s):
2044403
PAR ID:
10684510
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Energy Materials
Volume:
15
Issue:
28
ISSN:
1614-6832
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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