Self-assembled Cuprous Coordination Polymer as a Catalyst for CO₂ Electrochemical Reduction into C₂ Products

Abstract

C2 production with conventional metal complex catalysts has been a significant challenge. Here, we present the electrochemical reduction of CO2 into C2 products such as ethylene and ethanol with high selectivity using a self-assembled cuprous coordination polymer nanoparticle (Cu-SCP). The features of the Cu-SCP catalyst are the arrangement of Cu atoms in close proximity, similar to that in metallic Cu, and a stable Cu­(I) oxidation state throughout the reaction due to the coordination of ligands with Cu atoms, which inhibits conversion into Cu metal particles. The Cu-SCP also exhibits activity for C2 production that is superior to that of a Cu metal electrode, without modification of the carbon particles and/or ionomers or continuous flow of the highly alkaline electrolyte, which will simplify the fabrication of a CO2 electrolyzer. The Cu-SCP can be synthesized by a facile process that utilizes a heterogeneous reaction, and the product selectivity can be changed by replacement of the organic ligands, which should open up possibilities for the design of other CO2 reduction catalysts.

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

“…[12] Based on the peak position of Cu LMM spectra at % 570.1 eV,t he predominating copper species on the surface of CuOHFCl-4 and CuOHFCl-240 catalysts were Cu + after CO 2 RR test. [23] Forc omparison, ah alogen-free Cu(OH) 2 nanosheet sample was prepared and tested for CA at the…”

“… [24] Previously, the crucial role of Cu + sites or mixed Cu 0 ‐Cu + sites for the production of C 2+ products has been widely demonstrated by both theoretical and experimental studies [12, 17b, 25] . Various strategies have been developed for the purpose of construction and stabilization of Cu + or mixed Cu 0 ‐Cu + sites, such as hydroxide/oxide‐derived Cu‐based catalysts, [7d] plasma treatments, [25b] doping strategies, [8a, 26] ligand stabilization, [23b] core–shell structures, [17c, 27] and spatial confinement strategy [17a] . Therefore, the stability of cationic Cu sites (Cu + or mixed Cu 0 ‐Cu + ) is crucial to maintain the catalytic performance of Cu‐based electrocatalysts [7c, 18b, 23a] …”

Single‐Atom Electrocatalysts for Multi‐Electron Reduction of CO2

“…Reproduced with permission. [ 90 ] Copyright 2020, American Chemical Society. g) Illustration of the reversible transformation between single Cu atom and multiple Cu atoms in SACs during CO 2 RR.…”

Self‐Assembly and Aggregation‐Induced Emission in Aqueous Media of Responsive Luminescent Copper(I) Coordination Polymer Nanoparticles

“…All the complexes display strong yellow emission at room temperature in the solid‐state, which becomes dual luminescence at 77 K. Surprisingly, our findings suggest that in some of these systems TADF, instead of a phosphorescence pathway, is the origin of emission at room temperature. More importantly, we have observed the self‐assembled formation of coordination polymer nanoparticles (CPNs) in aqueous media, one of the first examples of Cu(I)‐based CPNs [38] . Finally, we followed the dynamic depolymerization process of [Cu 4 I 4 (L) 2 ] n CNPs formed in an aqueous environment, which revealed the responsiveness of their structural and emissive properties to media composition.…”