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[Display omitted] Carbon dioxide (CO 2) reduction is an urgent challenge worldwide due to the dramatically increased CO 2 concentration and concomitant environmental problems. Geological CO 2 storage in gas hydrate in marine sediment is a promising and attractive way to mitigate CO 2 emissions owning to its huge storage capability and safety. However, the sluggish kinetics and unclear enhancing mechanisms of CO 2 hydrate formation limit the practical application of hydrate-based CO 2 storage technologies. Here, we used vermiculite nanoflakes (VMNs) and methionine (Met) to investigate the synergistic promotion of natural clay surface and organic matter on CO 2 hydrate formation kinetics. Induction time and t 90 in VMNs dispersion with Met were shorter by one to two orders of magnitude than Met solution and VMNs dispersion. Besides, CO 2 hydrate formation kinetics showed significant concentration-dependence on both Met and VMNs. The side chains of Met can promote CO 2 hydrate formation by inducing water molecules to form a clathrate-like structure. However, when Met concentration exceeded 3.0 mg/mL, the critical amount of ammonium ions from dissociated Met distorted the ordered structure of water molecules, inhibiting CO 2 hydrate formation. Negatively charged VMNs can attenuate this inhibition by adsorbing ammonium ions in VMNs dispersion. This work sheds light on the formation mechanism of CO 2 hydrate in the presence of clay and organic matter which are the indispensable constituents of marine sediments, also contributes to the practical application of hydrate-based CO 2 storage technologies. [ABSTRACT FROM AUTHOR]

[Display omitted] Electrochemical reduction of CO 2 (CO 2 RR) to fuels and chemicals is a promising route to close the anthropogenic carbon cycle for sustainable society. The Cu-based catalysts in producing high-value hydrocarbons feature unique superiorities, yet challenges remain in achieving high selectivity. In this work, Cu@ZIF-8 NWs with highly-exposed Cu nanowires (Cu NWs) and ZIF-8 interface are synthesized via a surfactant-assisted method. Impressively, Cu@ZIF-8 NWs exhibit excellent stability and a high Faradaic efficiency of 57.5% toward hydrocarbons (CH 4 and C 2 H 4) at a potential of −0.7 V versus reversible hydrogen electrode. Computational calculations combining with experiments reveal the formation of Cu and ZIF-8 interface optimizes the adsorption of reaction intermediates, particularly stabilizing the formation of *CHO, thereby enabling efficient preference for hydrocarbons. This work highlights the potential of constructing metals and MOFs heterogeneous interfaces to enhance catalytic properties and offers valuable insights for the design of highly efficient CO 2 RR catalysts. [ABSTRACT FROM AUTHOR]