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Selective producing ethanol from CO2 electroreduction is highly demanded, yet the competing ethylene generation route is commonly more thermodynamically preferred. Herein, we reported an efficient CO2‐to‐ethanol conversion (53.5 % faradaic efficiency at −0.75 V versus reversible hydrogen electrode (vs. RHE)) over an oxide‐derived nanocubic catalyst featured with abundant "embossment‐like" structured grain‐boundaries. The catalyst also attains a 23.2 % energy efficiency to ethanol within a flow cell reactor. In situ spectroscopy and electrochemical analysis identified that these dualphase Cu(I) and Cu(0) sites stabilized by grain‐boundaries are very robust over the operating potential window, which maintains a high concentration of co‐adsorbed *CO and hydroxyl (*OH) species. Theoretical calculations revealed that the presence of *OHad not only promote the easier dimerization of *CO to form *OCCO (ΔG~0.20 eV) at low overpotentials but also preferentially favor the key *CHCOH intermediate hydrogenation to *CHCHOH (ethanol pathway) while suppressing its dehydration to *CCH (ethylene pathway), which is believed to determine the remarkable ethanol selectivity. Such imperative intermediates associated with the bifurcation pathway were directly distinguished by isotope labelling in situ infrared spectroscopy. Our work promotes the understanding of bifurcating mechanism of CO2ER‐to‐hydrocarbons more deeply, providing a feasible strategy for the design of efficient ethanol‐targeted catalysts. [ABSTRACT FROM AUTHOR]

The design of all-solid heterogeneous catalysts with frustrated Lewis pairs (FLPs) has attracted much attention recently because of their appealing low dissociation energy for H2 molecules due to which a promotion of hydrogenation reaction is expected. The sterically encumbered Lewis acid (metal site) and base (nitrogen site) in the cavity of single transition metal atom-doped M/C2N sheets make them potential candidates for the design of catalysts with FLPs, while a comprehensive understanding of their intrinsic property and reactivity is still lacking. Calculations show that the complete dissociation of the H2 molecule into two H* states at the N sites requires two steps: heterolytic cleavage of the H2 molecule and the transfer of H* from the metal site to the N site, which are strongly related to the acidity of the metal site. Ni/C2N and Pd/C2N, which outperform the other eight transition metal atom (M) anchored M/C2N candidates, possess low energy barriers for the complete dissociation of H2 molecules, with values of only 0.30 and 0.20 eV, respectively. Furthermore, both Ni/C2N and Pd/C2N catalysts can achieve semi-hydrogenation of C2H2 into C2H4, with overall barriers of 0.81 and 0.75 eV, respectively, which are lower than those reported for many other catalysts. It is speculated that M/C2N catalysts with intrinsic FLPs may also find applications in other important hydrogenation reactions. [ABSTRACT FROM AUTHOR]

The exploration of reticular chemistry pertaining to rod-packing metal–organic frameworks and the development of solid adsorbents for multitask hydrocarbon separations are two active topics of current research. In this study, an In-organic coordination framework compound denoted ZJNU-121 was assembled from a custom-designed bithiophene-functionalized tetracarboxylate ligand. The title compound not only exhibited a rare two-way rod-packing pattern but also displayed the impressive capability of capturing C2 hydrocarbons from CH4 and CO2 to achieve C2/C1 and C2/CO2 separations. Under ambient conditions, the ideal adsorbed solution theory-predicted adsorption selectivities for equimolar mixtures fall in the range of 8.4–13.8 (C2Hn/CH4) and 2.3–3.4 (C2Hn/CO2). Such separation potentials were also ascertained by the column breakthrough experiments. Furthermore, the in-depth theoretical insight unveiled the crucial role of active sites such as thiophene sulfur, carboxylate oxygen, and the bridging μ2-OH group in capturing C2 hydrocarbons in preference to CO2 and CH4. Additionally, the structural integrity of ZJNU-121 can be retained in aqueous solutions with pH values varying from 3 to 11 for 24 h at ambient temperature, as verified by the preservation of PXRD patterns, textural characteristics, and static/dynamic adsorption behaviors. This research not only enriched the architectural diversity of rod MOFs but also reported a robust adsorbent with good application prospects for diversified hydrocarbon separations. [ABSTRACT FROM AUTHOR]