Copper–Supramolecular Pair Catalyst Promoting C₂₊Product Formation in Electrochemical CO₂Reduction

Abstract

Electrochemical CO2 reduction (ECR) into value-added multicarbon products is a promising approach for a carbon-neutral economy. Heterogeneous molecular catalysts consist of atomic-precise, controllable active sites with the potential to improve catalytic activity by ligand design and engineering, yet most reported molecular ECR catalysts do not exhibit multicarbon product selectivity. Herein, we report the use of a copper–supramolecular pair as a crystalline molecular catalyst to promote the formation of multicarbon products. A combination of experimental and theoretical studies reveal that the paired Cu sites work collaboratively to activate the CO2 substrate and facilitate the coupling of adsorbed CO species although they are not bonded or bridged directly. The van der Waals interactions between the substrate and the secondary coordination sphere also play a crucial role in multicarbon product selectivity.

Making chemicals from the air: the new frontier for hybrid electrosyntheses in artificial tree-like devices

“…The studies on CO 2 RR to acetate have been focused mainly on using Cu-based electrocatalysts, assuming that copper is essential to realize the C-C coupling and thus produce acetate or other C2+ chemicals by CO 2 electroreduction. [214][215][216][217] However, this is in contrast with other literature results, as commented before, proving that (i) also other electrocatalysts not based on copper could form C2+ products selectively in CO 2 RR when there is a sufficient concentration of CO 2 adspecies, and (ii) selectivity in C2+ is determined from aspects not related to the electrocatalyst, such as electrode and cell design which determine the local concentration of reactants at the surface.…”

Mechanochemical Cu(ii) complexes and propargylamine synthetic adventures

“…Despite the simplicity of the task, we identified significant synthetic technical obstacles and the unavoidable use of a minimum amount of solvent to access the complexes in high purity. This notion is vital considering, for example, similar molecular scaffolds used in the electrochemical CO 2 reduction and formation of C 2+ products; 45 the presence of impurities may affect catalytic performance significantly, as is the case in this study.…”

“…All these factors are essential when applying these chiral complexes in the asymmetric A 3 coupling reactions or for redox purposes. 45 In solution, the complexes retain their chiral character (Fig S9†), and showcase a typical UV-Vis spectrum corresponding to a tetradentate N 2 O 2 chromophore (Fig S10†), while the ESI-MS data provide structures of the absolute formulae (Fig S11 and S12†).…”

New Insight into the Electronic Effect for Cu Porphyrin Catalysts in Electrocatalytic of CO2 into CH4

“…The results specify that all samples show a dominant Cu─N peak at ≈1.6 Å, and no other typical bonds for Cu─Cu contribution at 2.2 Å are detected. [21][22][23][24][25][26][27] Additionally, the EXAFS fitting results demonstrate that the coordination numbers of Cu─N of Cu─TRPP are closed to 4 (Figure S11 and Table S2, Supporting Information). All the results provide further validation of the successful synthesis of Cu─TRPPs.…”