Probing the Roles of Indium Oxides on Copper Catalysts for Enhanced Selectivity during CO₂-to-CO Electrochemical Reduction

Abstract

The electrochemical CO 2 reduction reaction (CO 2 RR) provides an alternative protocol to producing industrial chemicals with renewable electricity sources, and the highly selective, durable, and economic catalysts should expedite CO 2 RR applications. Here, we demonstrate a composite Cu−In 2 O 3 catalyst in which a trace amount of In 2 O 3 decorated on Cu surface greatly improves the selectivity and stability for CO 2 -to-CO reduction as compared to the counterparts (Cu or In 2 O 3 ), realizing a CO faradaic efficiency (FE CO ) of 95% at −0.7 V (vs RHE) and no obvious degradation within 7 h. In situ X-ray absorption spectroscopy reveals that In 2 O 3 undergoes the redox reaction and preserves the metallic state of Cu during the CO 2 RR process. Strong electronic interaction and coupling occur at the Cu/In 2 O 3 interface which serves as the active site for selective CO 2 RR. Theoretical calculation confirms the roles of In 2 O 3 in preventing oxidation and altering the electronic structure of Cu to assist COOH* formation and demote CO* adsorption at the Cu/In 2 O 3 interface.

Controlling the C1/C2+ product selectivity of electrochemical CO2 reduction upon tuning bimetallic CuIn electrocatalyst composition and operating conditions

“…Furthermore, the InCu 73 O x catalyst with the AEM showed comparable C 2+ selectivity and activity among the reported InCu-based electrocatalysts (Table S3†). 49,67,73–77 When we evaluated the performance of the InCu 73 O x catalyst with the AEM in the flow cell system, the faradaic efficiency of the overall C 2+ product was 21–37% from −0.6 V to −1 V vs. RHE, which was higher than those in the H-type cell system (Fig. 7c and 5c).…”

Structural and Chemical Evolution of an Inverse CeOx/Cu Catalyst under CO2 Hydrogenation: Tunning Oxide Morphology to Improve Activity and Selectivity

“…It is known that small nanoparticles of ZnO, ZrO 2 , InO x , and SnO x dispersed on copper also induce high catalytic activity for CO 2 reduction. [3][4][5][6]41,42 They can be very active for the splitting of H 2 and the binding/conversion of CO 2 . 6,9,41,42 The changes in composition and morphology seen in this study for the 5% CeO x /Cu system under different reaction conditions illustrate how dynamic the behavior of an inverse oxide/metal catalysts during CO 2 hydrogenation.…”

“…[3][4][5][6]41,42 They can be very active for the splitting of H 2 and the binding/conversion of CO 2 . 6,9,41,42 The changes in composition and morphology seen in this study for the 5% CeO x /Cu system under different reaction conditions illustrate how dynamic the behavior of an inverse oxide/metal catalysts during CO 2 hydrogenation. Small nanoparticles of an oxide on top of a metal substrate can adapt their structure and oxidation state in response to reactant molecules (CO 2 , H 2 , and CO 2 /H 2 ) in extreme ways not seen for a bulk oxide or a conventional metal on oxide configuration.…”

Cu26 Nanoclusters with Quintuple Ligand Shells for CO2 Electrocatalytic Reduction

“…Among the cluster-based catalysts, Cu nanoclusters have received increasing attention in CO 2 ER in the consideration of high abundance and the unique capability of copper to produce hydrocarbons. − The involvement of hydride species in most of Cu nanoclusters facilitates the study on metal-hydride materials in electrocatalysis as well. ,, For example, Jiang and co-workers revealed from both theoretical calculation and experimental test that CO 2 was reduced on a structurally precise Cu 32 H 20 L 12 (L = S 2 P­(O i Pr) 2 ) nanocluster via the lattice-hydride mechanism . Moreover, the group of Zang observed a significant influence of the structure of the Cu 8 cluster (cube vs ditetrahedron) on activity and selectivity in electrocatalytic CO 2 reduction reaction .…”