Effect of Charge on Carbon Support on the Catalytic Activity of Cu₂O toward CO₂ Reduction to C₂ Products

Abstract

Electrochemical carbon dioxide (CO 2 ) reduction for C 2 products has been studied on a series of supported Cu-based catalysts; however, the charge-promotion effects from the substrates for the selectivity of CO 2 reduction are still unclear.Here we localize nanosized Cu 2 O on three carbon-based substrates that provide different charge-promotion effects: positively charged boron-doped graphene (BG), negatively charged nitrogen-doped graphene (NG), and weak negatively charged reduced graphene oxide (rGO). We demonstrate that the charge-promotion effects lead to an increase in faradaic efficiency (FE) for C 2 products with an order of rGO/Cu < BG/Cu < pure Cu < NG/Cu and an FE Cd 2 /FE Cd 1 ratio from 0.2 to 7.1. By performing in situ characterization, electrokinetic investigations, and density functional theory (DFT) calculations, we reveal that the negatively charged NG is favorable for stabilizing Cu + species under CO 2 reduction, which strengthens CO* adsorption to further boost C−C coupling for C 2 products. As a result, we achieve a high C 2+ FE of ∼68% at high current densities of 100−250 mA cm −2 .

FeN4-Embedded Graphene as a Highly Sensitive and Selective Single-Atom Sensor for Reaction Intermediates of Electrochemical CO2 Reduction

“…The large-scale use of fossil energy has emitted a large amount of carbon dioxide (CO 2 ), causing many environmental problems, such as air pollution and global warming. , The electrochemical reduction of CO 2 to high-value chemicals by the electrochemical reduction method provides a promising way for the conversion and storage of electrical energy generated by renewable energy sources and also contributes to the mitigation of environmental problems. − It is worth noting that the electrochemical CO 2 reduction reaction (CO 2 RR) is a multi-electron reaction involving complex intermediates, numerous products, and complicated reaction pathways. , Therefore, real-time detection of the reaction intermediates becomes particularly significant for understanding the reaction mechanism and further optimizing CO 2 reduction catalytic performance.…”

“…3−5 It is worth noting that the electrochemical CO 2 reduction reaction (CO 2 RR) is a multi-electron reaction involving complex intermediates, numerous products, and complicated reaction pathways. 6,7 Therefore, real-time detection of the reaction intermediates becomes particularly significant for understanding the reaction mechanism and further optimizing CO 2 reduction catalytic performance.…”

Surface-Enhanced Raman Spectroscopy for Boosting Electrochemical CO2 Reduction on Amorphous-Surfaced Tin Oxide Supported by MXene

“…To mitigate the impact of human-induced climate deterioration, electrocatalytic CO 2 reduction reactions (CO 2 RR) present a promising strategy for transforming CO 2 into high-value chemicals or fuels . A wide range of CO 2 RR products, including carbon monoxide (CO), methane (CH 4 ), formic acid, or formate (HCOOH/HCOO – ), can be harnessed through appropriately engineered catalysts . Among these, liquid products such as formate are commercially advantageous due to their lower toxicity, higher energy density, and facile storage and transportation .…”