Electrochemical Reduction of Carbon Dioxide by in-situ Generated Hydrogen at Porous Cu-Fe Foam-Like Catalysts: Efficiency Towards Formic Acid Formation

Ghaith, Mohamed; Abdelrahim, Ahmed; Saada, Aya; El Saied, Mohamed; Attia, Attia M; El-Sherif, Ahmed; El-Deab, Mohamed S.

doi:10.21608/ejchem.2025.401455.12010

Electrochemical Reduction of Carbon Dioxide by in-situ Generated Hydrogen at Porous Cu-Fe Foam-Like Catalysts: Efficiency Towards Formic Acid Formation

Articles in Press

Document Type : Original Article

Authors

¹ Department of Chemistry, Faculty of Science, Cairo University

² Faculty of Energy and Environmental Engineering, The British University in Egypt

³ Egyptian Petroleum Research Institute, Nasr City, Cairo, Egypt

⁴ The British University in Egypt

⁵ organometallic Department of Chemistry, Faculty of Science, Cairo University, Cairo, Egypt

⁶ Department of Chemistry, Faculty of Science, Cairo University, Cairo, Egypt

10.21608/ejchem.2025.401455.12010

Abstract

This paper addresses the electrocatalytic reduction of carbon dioxide (CO2ER) to combat the excessive emissions from heavy industries like steel and cement. This is much done with an aim to prepare liquid fuels (e.g., formic acid) by electrochemical reduction of CO2 (CO2 ER) by the in-situ generated hydrogen gas at binary Cu-Fe porous catalysts. The dynamic hydrogen bubble template (DHBT) technique was used to prepare the porous catalyst layer atop a planar Cu electrode. The simultaneous generation of hydrogen gas at the Cu-Fe binary porous catalyst assisted in directing the selectivity of CO2ER towards formic acid. The exhaustive electrolysis (for 5 hr at –1.7 V) of CO2-saturated 0.1 M NaHCO3 resulted in about 0.028 M formic acid as a detectable liquid reduction product of CO2 at Cu60Fe40, compared to about 0.015 M at the Cu electrode, as revealed from electrochemical analysis. The observed enhancement towards formic acid formation was rationalized by DFT calculations. That is the addition of Fe to Cu enhances the affinity of CO2 adsorption on the surface of the Fe-Cu catalyst, together with less adsorptivity (lowering of adsorption energy) of the generated hydrogen radicals (reactive reducing species), allowing for the favorable interaction with CO2•– radical anion on the binary catalyst surface. Thus, it promotes the production of formic acid.

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