Controlling the Surface Oxidation of Cu Nanowires Improves Their Catalytic Selectivity and Stability toward C₂₊ Products in CO₂ Reduction

Abstract

Copper nanostructures are promising catalysts for the electrochemical reduction of CO 2 because of their unique ability to produce alarge proportion of multi-carbon products. Despite great progress,t he selectivity and stability of such catalysts still need to be substantially improved. Here,w e demonstrate that controlling the surface oxidation of Cu nanowires (CuNWs) can greatly improve their C 2+ selectivity and stability.S pecifically,w ea chieve af aradaic efficiency as high as 57.7 and 52.0 %f or ethylene when the CuNWs are oxidized by the O 2 from air and aqueous H 2 O 2 ,r espectively, and both of them showh ydrogen selectivity below1 2%.T he high yields of C 2+ products can be mainly attributed to the increase in surface roughness and the generation of defects and cavities during the electrochemical reduction of the oxide layer. Our results also indicate that the formation of arelatively thick, smooth oxide sheath can improve the catalytic stability by mitigating the fragmentation issue.

Residual Chlorine Induced Cationic Active Species on a Porous Copper Electrocatalyst for Highly Stable Electrochemical CO2 Reduction to C2+

“…Similarly, the coarsen of the dendritic Cu nanostructures in the course of CO 2 RR resulted in the loss of high index facets, which was believed to be responsible for the degradation of catalytic performance [13a, 14a] . A recent study demonstrated that a thicker and smoother Cu x O protective layer obtained by controlled surface oxidation could inhibit the disintegration of Cu nanowires and improve its catalytic stability to more than 22 h [15b] . In this study, it was demonstrated that abundant active sites that were induced under CO 2 RR conditions were well‐retained even after 240 h of electrocatalysis, which may be due to the thermodynamical stability of these active sites under CO 2 RR conditions [16] .…”

“…To mitigate the disintegration of structure and the loss of active sites,g raphene oxide wrapped and thick CuO x outer layer protected Cu nanowires showed enhanced stability for both structure and catalytic performance. [15] Recently,aCu nanowire catalyst was reported to maintain ah igh selectivity toward C 2 H 4 for over 200 hours of electrocatalysis,p ointing out the importance of stable stepped sites that formed through in situ during electrochemical activation. [16] Therefore,i ti so fg reat importance to maintain the stability of catalyst structure and active sites for improving the catalytic performance of Cu-based CO 2 RR electrocatalysts.O nt he other hand, although the conclusion is still pending, the crucial role of oxidized Cu species for the improvement of C 2+ production has been widely investigated.…”

Efficient CO2 Electroreduction on Ag2S Nanodots Modified CdS Nanorods as Cooperative Catalysts

“…Especially, the reduction process with two‐electron transfer, in which generating CO and formate, is economically viable according to the techno‐economic analysis [5] . Numerous efforts are thus focused on designing efficient electrocatalysts for CO 2 ‐to‐CO reduction with high Faradaic efficiency (FE) and high activity (such as CO partial current density) [6–9] . To date, carbon‐based materials, [6] noble metals (such as Ag), [7] metal oxides (CuO x and ZnO) [8,9] and metal chalcogenides (CdS and MoSe x ) [10–14] have been developed for electrochemically producing CO.…”

“…Numerous efforts are thus focused on designing efficient electrocatalysts for CO 2 ‐to‐CO reduction with high Faradaic efficiency (FE) and high activity (such as CO partial current density) [6–9] . To date, carbon‐based materials, [6] noble metals (such as Ag), [7] metal oxides (CuO x and ZnO) [8,9] and metal chalcogenides (CdS and MoSe x ) [10–14] have been developed for electrochemically producing CO. Among them, the stable nanorod‐like CdS electrocatalyst shows excellent CO FE of >95 % in aqueous solution by suppressing the competing hydrogen evolution reaction [12–14] .…”

Electrochemical C–N coupling with perovskite hybrids toward efficient urea synthesis

“…[1][2][3] On the other hand, carbon dioxide (CO 2 ) generated from industries and transportation is the principal greenhouse gas causing serious environmental concerns. [4][5][6][7][8] Thus, converting N 2 and CO 2 into value-added fuels and chemical products via the C-N coupling reaction is a promising approach for not only mitigating environmental issues and energy crisis but also high-value utilization of N 2 and CO 2 . [9][10][11][12] However, the highly stable double-bond (C]O, 806 kJ mol À1 ) in CO 2 molecules and the triple-bond (N^N, 940.95 kJ mol À1 ) in N 2 molecules make the inert gas molecules difficult to activate mildly.…”