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The electrochemical reductive valorization of CO2, referred to as the CO2RR, is an emerging approach for the conversion of CO2‐containing feeds into valuable carbonaceous fuels and chemicals, with potential contributions to carbon capture and use (CCU) for reducing greenhouse gas emissions. Copper surfaces and graphene‐embedded, N‐coordinated single metal atom (MNC) catalysts exhibit distinctive reactivity, attracting attention as efficient electrocatalysts for CO2RR. This review offers a comparative analysis of CO2RR on copper surfaces and MNC catalysts, highlighting their unique characteristics in terms of CO2 activation, C1/C2(+) product formation, and the competing hydrogen evolution pathway. The assessment underscores the significance of understanding structure–activity relationships to optimize catalyst design for efficient and selective CO2RR. Examining detailed reaction mechanisms and structure‐selectivity patterns, the analysis explores recent insights into changes in the chemical catalyst states, atomic motif rearrangements, and fractal agglomeration, providing essential kinetic information from advanced in/ex situ microscopy/spectroscopy techniques. At the end, this review addresses future challenges and solutions related to today's disconnect between our current molecular understanding of structure–activity‐selectivity relations in CO2RR and the relevant factors controlling the performance of CO2 electrolyzers over longer times, with larger electrode sizes, and at higher current densities. [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]

Trifluoromethyl‐bearing 5‐membered rings are prevalent in bioactive molecules, but modular approaches to these compounds by functionalization of robust C(sp3)−H bonds in a direct and selective manner are extremely challenging. Herein we report the rhodium‐catalyzed α‐CF3‐α‐alkyl carbene insertion into C(sp3)−H bonds of a broad range of substrates to access 7 types of CF3‐bearing saturated 5‐membered carbo‐ and heterocycles. The reaction is particularly effective for benzylic C−H insertion exerting good site‐, diastereo‐ and enantiocontrol, and applicable to the synthesis of chiral CF3 analogues of bioactive molecules. Ruthenium α‐CF3‐α‐alkyl carbene complexes underwent stoichiometric reactions to give C−H insertion products, lending evidence for the involvement of metal α‐CF3‐α‐alkyl carbene species in the catalytic cycle. DFT calculations revealed that the π⋅⋅⋅π attraction and intra‐carbene C−H⋅⋅⋅F hydrogen bond elucidate the origin of selectivity of the benzylic C−H insertion reactions. [ABSTRACT FROM AUTHOR]

Nucleic acid (NA) computation has been widely developed in the past years to solve kinds of logic and mathematic issues in both information technologies and biomedical analysis. However, the difficulty to integrate non‐NA molecules limits its power as a universal platform for molecular computation. Here, we report a versatile prototype of hybridized computation integrated with both nucleic acids and non‐NA molecules. Employing the conformationally controlled ligand converters, we demonstrate that non‐NA molecules, including both small molecules and proteins, can be computed as nucleic acid strands to construct the circuitry with increased complexity and scalability, and can be even programmed to solve arithmetical calculations within the computational nucleic acid system. This study opens a new door for molecular computation in which all‐NA circuits can be expanded with integration of various ligands, and meanwhile, ligands can be precisely programmed by the nuclei acid computation. [ABSTRACT FROM AUTHOR]

Metal‐free and metal‐containing molecular trefoil knots are fascinating ensembles that are usually covalently assembled, the latter requiring the rational design of di‐ or multidentate/multipodal ligands as connectors. In this work, we describe the self‐assembly of pentadecanuclear AuI trefoil knots [Au15(C≡CR)15] from monoalkynes HC≡CR (R=9,9‐X2‐fluorenyl with X=nBu, n‐hexyl) and [AuI(THT)Cl]. Hetero‐bimetallic counterparts [Au9M6(C≡CR)15] (M=Cu/Ag) were self‐assembled by reactions of [Au15(C≡CR)15] with [Cu(MeCN)4]+/AgNO3 and HC≡CR. The type of pentadecanuclear trefoil knots described herein is characterized by X‐ray crystallography, 2D NMR and HR‐ESI‐MS. [Au9Cu6(C≡CR)15] is relatively stable in hexane; its excited state properties were investigated. DFT calculations revealed that non‐covalent metal–metal and metal–ligand interactions, together with longer alkyl chain‐strengthened inter‐ligand dispersion interactions, govern the stability of the trefoil knot structures. [ABSTRACT FROM AUTHOR]

A transition‐metal‐free C(sp2)−C(sp2) bond formation reaction by the cross‐coupling of diazo quinones with catechol boronic esters was developed. With this protocol, a variety of biaryls and alkenyl phenols were obtained in good to high yields under mild conditions. The reaction tolerates various functionalities and is applicable to the derivatization of pharmaceuticals and natural products. The synthetic utility of the method was demonstrated by the short synthesis of multi‐substituted triphenylenes and three bioactive natural products, honokiol, moracin M, and stemofuran A. Mechanistic studies and density functional theory (DFT) calculations revealed that the reaction involves attack of the boronic ester by a singlet quinone carbene followed by a 1,2‐rearrangement through a stepwise mechanism. [ABSTRACT FROM AUTHOR]

Abstract: Solar CO2 reduction efficiency is largely limited by poor photoabsorption, sluggish electron–hole separation, and a high CO2 activation barrier. Defect engineering was employed to optimize these crucial processes. As a prototype, BiOBr atomic layers were fabricated and abundant oxygen vacancies were deliberately created on their surfaces. X‐ray absorption near‐edge structure and electron paramagnetic resonance spectra confirm the formation of oxygen vacancies. Theoretical calculations reveal the creation of new defect levels resulting from the oxygen vacancies, which extends the photoresponse into the visible‐light region. The charge delocalization around the oxygen vacancies contributes to CO2 conversion into COOH* intermediate, which was confirmed by in situ Fourier‐transform infrared spectroscopy. Surface photovoltage spectra and time‐resolved fluorescence emission decay spectra indicate that the introduced oxygen vacancies promote the separation of carriers. As a result, the oxygen‐deficient BiOBr atomic layers achieve visible‐light‐driven CO2 reduction with a CO formation rate of 87.4 μmol g−1 h−1, which was not only 20 and 24 times higher than that of BiOBr atomic layers and bulk BiOBr, respectively, but also outperformed most previously reported single photocatalysts under comparable conditions. [ABSTRACT FROM AUTHOR]

Electroreduction of CO2 into hydrocarbons could contribute to alleviating energy crisis and global warming. However, conventional electrocatalysts usually suffer from low energetic efficiency and poor durability. Herein, atomic layers for transition-metal oxides are proposed to address these problems through offering an ultralarge fraction of active sites, high electronic conductivity, and superior structural stability. As a prototype, 1.72 and 3.51 nm thick Co3O4 layers were synthesized through a fast-heating strategy. The atomic thickness endowed Co3O4 with abundant active sites, ensuring a large CO2 adsorption amount. The increased and more dispersed charge density near Fermi level allowed for enhanced electronic conductivity. The 1.72 nm thick Co3O4 layers showed over 1.5 and 20 times higher electrocatalytic activity than 3.51 nm thick Co3O4 layers and bulk counterpart, respectively. Also, 1.72 nm thick Co3O4 layers showed formate Faradaic efficiency of over 60% in 20 h. [ABSTRACT FROM AUTHOR]

Solar CO2 reduction into hydrocarbons helps to solve the global warming and energy crisis. However, conventional semiconductors usually suffer from low photoactivity and poor photostability. Here, atomically-thin oxide-based semiconductors are proposed as excellent platforms to overcome this drawback. As a prototype, single-unit-cell Bi2WO6 layers are first synthesized by virtue of a lamellar Bi-oleate intermediate. The single-unit-cell thickness allows 3-times larger CO2 adsorption capacity and higher photoabsorption than bulk Bi2WO6. Also, the increased conductivity, verified by density functional theory calculations and temperature-dependent resistivities, favors fast carrier transport. The carrier lifetime increased from 14.7 to 83.2 ns, revealed by time-resolved fluorescence spectroscopy, which accounts for the improved electron-hole separation efficacy. As a result, the single-unit-cell Bi2WO6 layers achieve a methanol formation rate of 75 µmol g-1 h-1, 125-times higher than that of bulk Bi2WO6. The catalytic activity of the single-unit-cell layers proceeds without deactivation even after 2 days. This work will shed light on designing efficient and robust photoreduction CO2 catalysts. [ABSTRACT FROM AUTHOR]

A model of doping confined in atomic layers is proposed for atomic-level insights into the effect of doping on photocatalysis. Co doping confined in three atomic layers of In2S3 was implemented with a lamellar hybrid intermediate strategy. Density functional calculations reveal that the introduction of Co ions brings about several new energy levels and increased density of states at the conduction band minimum, leading to sharply increased visible-light absorption and three times higher carrier concentration. Ultrafast transient absorption spectroscopy reveals that the electron transfer time of about 1.6 ps from the valence band to newly formed localized states is due to Co doping. The 25-fold increase in average recovery lifetime is believed to be responsible for the increased of electron-hole separation. The synthesized Co-doped In2S3 (three atomic layers) yield a photocurrent of 1.17 mA cm−2 at 1.5 V vs. RHE, nearly 10 and 17 times higher than that of the perfect In2S3 (three atomic layers) and the bulk counterpart, respectively. [ABSTRACT FROM AUTHOR]

Inside Back Cover: Self-Assembly of Molecular Trefoil Knots Featuring Pentadecanuclear Homoleptic AuI-, AuI/AgI-, or AuI/CuI-Alkynyl Coordination (Angew. Gold, Metal-Alkynyl Complexes, Metal-Metal Interactions, Supramolecular Chemistry, Trefoil Knots Keywords: Gold; Metal-Alkynyl Complexes; Metal-Metal Interactions; Supramolecular Chemistry; Trefoil Knots EN Gold Metal-Alkynyl Complexes Metal-Metal Interactions Supramolecular Chemistry Trefoil Knots 1 1 1 05/11/22 20220516 NES 220516 B Molecular trefoil knots b are usually covalently assembled from rationally designed building blocks with multiple functional groups. [Extracted from the article]

A conceptually new all-solid-state asymmetric supercapacitor based on atomically thin sheets is presented which offers the opportunity to optimize supercapacitor properties on an atomic level. As a prototype, β-Co(OH)2 single layers with five-atoms layer thickness were synthesized through an oriented-attachment strategy. The increased density-of-states and 100 % exposed hydrogen atoms endow the β-Co(OH)2 single-layers-based electrode with a large capacitance of 2028 F g−1. The corresponding all-solid-state asymmetric supercapacitor achieves a high cell voltage of 1.8 V and an exceptional energy density of 98.9 Wh kg−1 at an ultrahigh power density of 17 981 W kg−1. Also, this integrated nanodevice exhibits excellent cyclability with 93.2 % capacitance retention after 10 000 cycles, holding great promise for constructing high-energy storage nanodevices. [ABSTRACT FROM AUTHOR]