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Sustainable multicarbon e‐chemicals are of particular interest due to their potential future, high market values, and demand. In the direct electrocatalytic formation of multicarbon e‐chemicals from CO2, the elementary C–C coupling by CO dimerization is considered the rate‐limiting step. Here, a generalized surface structural design principle of asymmetric metal pair sites is proposed, explored, and experimentally tested in order to promote CO dimerization on surfaces. First a computational model of N‐doped Cu2S layers featuring adjacent, electronically asymmetric Cuδ1+‐Cuδ2+ (0 < δ1+ < δ2+ < 1) metal atomic pairs evidenced by their non‐uniform charge distribution is considered. The electronic asymmetry resulted in distinct CO adsorption energies and the associated self‐adjusting structures, which lowered C–C coupling energy barriers significantly. The computational hypotheses are experimentally tested using X‐ray photoelectron spectroscopy of Cu‐N moieties within N‐doped Cu2S layers. In‐situ Fourier‐transform infrared spectroscopy confirms linear *CO and *CO‐CO adsorption configuration by the peaks of ≈2080 and 1920 cm−1, respectively. After N‐doping, the catalytically C2 faradaic efficiency can significantly be elevated to 14.72% due to the promotion of C–C coupling. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Surface-attached architectures of p(MEO2MA-co-OEGMA) copolymers are thermoresponsive PEG analogues with potential applications in biotechnology and medicine. In this respect, structure and dynamics of polymer brushes made of these copolymers are of great interest. In this work, the near surface dynamics of a p(MEO2MA-co-OEGMA) brush with a height of 250 nm was investigated with neutron spin echo spectroscopy under grazing incidence (GINSES) conditions. The brush dynamics was studied at two penetration depths of the neutrons. An influence of the distance from the confining surface on the collective diffusion was found. For the first time, the experiment demonstrates the feasibility of studying thermal fluctuations of macromolecules at a single planar liquid/solid interface by neutron spin echo spectroscopy under grazing incidence. [ABSTRACT FROM AUTHOR]

The chemical selectivity and faradaic efficiency of high-index Cu facets for the CO 2 reduction reaction (CO 2 RR) 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 CH 4  : 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., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)