Electrochemical Reduction of CO₂ Catalyzed by Fe-N-C Materials: A Structure–Selectivity Study

Abstract

Selective electrochemical reduction of CO 2 into energy-dense organic compounds is a promising strategy for using CO 2 as a carbon source. Herein, we investigate a series of iron-based catalysts synthesized by pyrolysis of Fe-, N-and C-containing precursors for the electroreduction of CO 2 to CO in aqueous conditions and demonstrate that the selectivity of these materials for CO 2 reduction over proton reduction is governed by the ratio of isolated FeN 4 sites vs. Fe-based nanoparticles. This ratio can be synthetically tuned to generate electrocatalysts producing controlled CO/H 2 ratios. It notably allows preparing materials containing only FeN 4 sites, which are able to selectively reduce CO 2 to CO in aqueous solution with Faradaic yields over 90% and at low overpotential. KEYWORDS. CO 2 reduction-electrocatalysis-iron-Fe-N-C materials-Structure-selectivity relationship.

Catalytic Mechanisms and Design Principles for Single‐Atom Catalysts in Highly Efficient CO2 Conversion

“…We have calculated the overpotentials for the Co-N x -C SACs with different coordination environments (x = 0-4) ( Figure S20, Supporting Information) and found that the Co-N 4 -C structures have the lowest overpotentials, which favors CO 2 RR over HER. [44,[46][47][48][49][50][51] Though relying on this certain case only, the discovered descriptors can be considered as effectively universal design principles of various M-N-C SACs for highly efficient CO 2 conversion. Therefore, the M-N 4 -C structures are dominant active centers among the various M-N-C structures.…”

Highly Efficient Electroreduction of CO2 to Methanol on Palladium–Copper Bimetallic Aerogels

“…Aerogels have fine inorganic superstructure with high porosity and are knowntobeexceptional materials.Now aPd ÀCu bimetallic aerogel electrocatalyst has been developed for conversion of CO 2 into CH 3 OH. [10] However, substantial advances for searching new electrodes in CO 2 RR are still needed to meet the criteria for practical applications.Generally,Cuisthe metal electrochemical catalyst that is uniquely capable of reducing CO 2 to aseries of hydrocarbons, acids,a nd alcohols with comparative Faradaic efficiency. The superior performance of the electrocatalyst results from efficient adsorption and stabilization of the CO 2 radical anion, high Pd 0 /Pd II and Cu I + Cu 0 /Cu II ratios, and sufficient Pd/Cu grain boundaries of aerogel nanochains.…”

“…The current density and Faradaic efficiency of CH 3 OH can be as high as 31.8 mA cm À2 and 80.0 %o ver the Pd 83 Cu 17 aerogel at av ery low overpotential (0.24 V). [10] However,there are still some drawbacks for Cu electrodes for CO 2 RR, such as high overpotential, wide product distribu-Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi. [1] Theinterest in electrochemical CO 2 reduction reaction (CO 2 RR) has sparked as ustained research effort.…”

“…[1] Theinterest in electrochemical CO 2 reduction reaction (CO 2 RR) has sparked as ustained research effort. [10] However, substantial advances for searching new electrodes in CO 2 RR are still needed to meet the criteria for practical applications. [2][3][4][5][6][7] In particular, numerous efforts have been dedicated to developing and improving the performance of metal catalysts for CO 2 RR, [8,9] among which controlling the size,s hape,a nd morphology of nanostructured metals is an effective strategy.…”

“…[10] However,there are still some drawbacks for Cu electrodes for CO 2 RR, such as high overpotential, wide product distribu-Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi. [10] However,there are still some drawbacks for Cu electrodes for CO 2 RR, such as high overpotential, wide product distribu-Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.…”