Computational studies of electrochemical CO₂ reduction on subnanometer transition metal clusters

Abstract

Computational studies of electrochemical reduction of CO2 to CO, HCOOH and CH4 were carried out using tetra-atomic transition metal clusters (Fe4, Co4, Ni4, Cu4 and Pt4) at the B3LYP level of theory. Novel catalytic properties were discovered for these subnanometer clusters, suggesting that they may be good candidate materials for CO2 reduction. The calculated overpotentials for producing CH4 are in the order, Co4 < Fe4 < Ni4 < Cu4 < Pt4, with both Co4 and Fe4 having overpotentials less than 1 V. Investigation of the effects of supports found that a Cu4 cluster on a graphene defect site has a limiting potential for producing CH4 comparable to that of a Cu (111) surface. However, due to the strong electronic interaction with the Cu4 cluster, the defective graphene support has the advantage of significantly increasing the limiting potentials for the reactions competing with CH4, such as the hydrogen evolution reaction (HER) and CO production.

Hydride Pinning Pathway in the Hydrogenation of CO2 to Formic Acid on Dimeric Tin Dioxide

“…Selective CO 2 reduction to formic acid has also been studied on other metal clusters,, metal complexes, ionic liquids, transition metal surfaces,, metal‐hydride, and surfaces of In 2 O 3 , CeO 2 , ZnO etc ,. On the Cu‐hydride nanocluster, CO 2 reduction follows a different mechanism where CO 2 is activated in the influence of lattice hydride and forms a formate intermediate at an overpotential of 0.32 eV .…”

A metal-free electrocatalyst for carbon dioxide reduction to multi-carbon hydrocarbons and oxygenates

“…Therefore, more efforts have to be devoted, to develop more powerful catalysts for efficient CO 2 conversion to multi-carbon hydrocarbons and oxygenates. Reducing the structural features to sub-nanometre dimensions often significantly enhances the hydrogenation activity for metal catalysts and it even has been demonstrated to transform a non-catalytic active bulk counterpart into a highly active catalyst towards CO 2 reduction14151617. Separately, the introduction of additional defects in carbon nanostructures by heteroatom doping gives rise to activity toward CO 2 activation6781819.…”

Surface structure and composition effects on electrochemical reduction of carbon dioxide

“…Kauffman et al [35] found ligand-protected Au 25 clusters had spontaneous and reversible electronic interactions with CO 2 molecules, which led to a lower overpotential for CO formation and a higher CO production rate in a CO 2 -saturated dimethylformamide (DMF) solution with 0.1 M TBAP as the electrolyte. Liu et al [36] proposed that Co 4 and Fe 4 might be good candidates for CO 2 reduction due to small overpotentials (less than 1 V), based on theoretical calculations on a few tetra-atomic metal (Co, Fe, Ni, Cu, Pt) clusters. In addition, these ultrafine clusters showed strong interactions with the supporting materials.…”