Electroreduction of CO₂ on Au(310)@Cu High‐index Facets

Abstract

The chemical selectivity and faradaic efficiency of high‐index Cu facets for the CO2 reduction reaction (CO2RR) is investigated. More specifically, shape‐controlled nanoparticles enclosed by Cu {hk0} facets are fabricated using Cu multilayer deposition at three distinct layer thicknesses on the surface facets of Au truncated ditetragonal nanoprisms (Au DTPs). Au DTPs are shapes enclosed by 12 high‐index {310} facets. Facet angle analysis confirms DTP geometry. Elemental mapping analysis shows Cu surface layers are uniformly distributed on the Au {310} facets of the DTPs. The 7 nm Au@Cu DTPs high‐index {hk0} facets exhibit a CH4 : CO product ratio of almost 10 : 1 compared to a 1 : 1 ratio for the reference 7 nm Au@Cu nanoparticles (NPs). Operando Fourier transform infrared spectroscopy spectra disclose reactive adsorbed *CO as the main intermediate, whereas CO stripping experiments reveal the high‐index facets enhance the *CO formation followed by rapid desorption or hydrogenation.

Electrocatalytic and Photocatalytic CO2 Methanation: From Reaction Fundamentals to Catalyst Developments

“…[76] It is demonstrated that the exposure of Cu high-index facets and a thicker (7 nm) Cu layer favored the formation and hydrogenation of *CO, which in turn promoted CH 4 production. [76] In summary, precise optimization of the catalytic performance is mainly achieved by modulating the catalytic crystalline facets and active site exposure.…”

“…[72] Furthermore, the adsorption edge position of samples compared with Cu foil and CuO foil, which was obtained from XANES (Figure 3b), inferred the valence state of Cu. [43,72] The morphological and structural dependence in electrocatalytic CO 2 methanation, such as the external shape, [74] surface feature, [75] and crystalline structure [76] of the electrocatalysts, has been proved. For example, nanosheets were reported to provide direct channels for electron and proton transfer, facilitating charge transfer and mass transfer, optimizing active sites, and thus improving catalytic activity.…”

Electronic Structure Design of Transition Metal-Based Catalysts for Electrochemical Carbon Dioxide Reduction

“…Moreover, surface vacancies construct a rough surface that contain abundant dangling bonds and active valence electrons, resembling the high-index crystal facets. , For example, Wang et al reported quasi-spherical Cu 2 O with a rough surface and O vacancies (Cu 2 O/ILGS-400) (Figure b), instead of block shape with low-index exposed facets. In this configuration, the oxidation states were intermediate between Cu foil and Cu 2 O, facilitating the coverage and adsorption of CO to form C–C bonds.…”

Cu‐Based Catalytic Materials for Electrochemical Carbon Dioxide Reduction: Recent Advances and Perspectives

“…[ 62 ] Liang Liang et al found that Au‐truncated tetragonal nanoprisms (Au DTPs) enclosed by 12 high‐index facets‐supported Cu surface yielded a CH 4 /CO ratio of 10:1 compared with a ratio of 1:1 for 7 nm Au@Cu nanoparticles (NPs). [ 63 ] Tang et al demonstrated that entangled Cu nanowires with hierarchical pores in the presence of I − exhibited a C 2 FE of 80%, and the enhanced CRR activities could be derived from CO intermediate enrichment inside the hierarchical pores. [ 64 ] Hui Li et al created a Cu nanocrystal with a highly exposed facet ratio of (100)/(111) via facet‐selective atomic layer deposition technique to selectively cover the (111) surface of Cu with ultrathin Al 2 O 3 , resulting in a 22 times enhanced FE ratio of C 2 H 4 /CH 4 and a maximum FE of 60.4% for C 2 H 4.…”