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Precisely regulating surface reconstruction of copper (Cu) chalcogenides‐based catalysts to promote the multicarbon (C2+)selectivity of the electrochemical CO2 reduction reaction (CO2RR) is hampered by the challenging control of the intractable anions and the optimal Cuδ+ reduction (0 < δ < 1). Herein, a porous carbon‐supported copper selenides electrocatalyst that can remarkably improve the C2‐product yield and especially unveil the time‐revolved electrochemical CO2RR reconstruction process to enable the high C2‐selectivity, most notably for ethanol is constructed. The Faradic efficiency (FE) of C2‐products achieved is as high as ≈85.2% with a partial current density of 229.5 mA cm−2. Operando infrared spectroscopy and density functional theory (DFT) calculations unravel that the surface Se vacancies (VSe) formation brings closer the neighboring Cu+ atoms and activates the Cu sites, thereby rendering efficient generation of the key intermediates (*CO and *CHO) and lowering the C–C coupling barrier for C2 production. The appearance of metallic Cu can shorten the next‐nearest Cu0–Cu+ distance for O atom to bridge in, leading to the preferential formation of *OC2H4 towards ethanol instead of C–O bond cleavage to form ethylene. This work opens the avenue of designing suitable local atomic structures catalysts to engage the intermediates for targeted CO2RR products. [ABSTRACT FROM AUTHOR]

Electrocatalytic reduction of CO2 to formate is believed to be one of the most promising technologies for producing clean fuels and valuable chemicals and for tackling the global warming problem. Herein, a novel synthesis strategy is presented for Bi‐based catalyst in CO2 reduction reaction (CO2RR). With the addition of acetic acid into the mother solution, heterostructured Bi/Bi2O3 nanoplates with abundant O vacancies (Bi/Bi2O3–Ov) and tailored coordination environments of the Bi ions are successfully synthesized, which exhibit excellent catalytic activity for CO2RR and high selectivity for formate generation with wide operable windows of pH (neutral to alkaline) and potential. In particular, the faradic efficiency (HCOOH) reaches ≥90% in a wide potential range of −0.7–−1.35 V versus reversible hydrogen electrode in neutral media, which dwarf most of the state‐of‐the‐art Bi‐based catalysts for CO2RR reported to date. Combined experimental and theoretical results show that the abundant O vacancies create frustrated Lewis pairs at the heterointerfaces with favorable adsorption characteristics, thereby facilitating the CO2RR process. This work opens up a new approach to promoting the catalytic activity and selectivity of Bi‐based materials for CO2RR by combining coordination and heterointerface engineering. [ABSTRACT FROM AUTHOR]

Copper-based catalysts are efficient for CO 2 reduction affording commodity chemicals. However, Cu(i) active species are easily reduced to Cu(0) during the CO 2 RR, leading to a rapid decay of catalytic performance. Herein, we report a hybrid-catalyst that firmly anchors 2D-Cu metallic dots on F-doped Cu x O nanoplates (Cu x OF), synthesized by electrochemical-transformation under the same conditions as the targeted CO 2 RR. The as-prepared Cu/Cu x OF hybrid showed unusual catalytic activity towards the CO 2 RR for CH 3 COO - generation, with a high FE of 27% at extremely low potentials. The combined experimental and theoretical results show that nanoscale hybridization engenders an effective s,p-d coupling in Cu/Cu x OF, raising the d-band center of Cu and thus enhancing electroactivity and selectivity for the acetate formation. This work highlights the use of electronic interactions to bias a hybrid catalyst towards a particular pathway, which is critical for tuning the activity and selectivity of copper-based catalysts for the CO 2 RR., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Efficient noble-metal free electrocatalyst for oxygen evolution reaction (OER) is critical for large-scale hydrogen production via water splitting. Inspired by Nature's oxygen evolution cluster in photosystem II and the highly efficient artificial OER catalyst of NiFe layered double hydroxide (LDH), we designed an electrostatic 2D-2D assembly route and successfully synthesized a 2D LDH(+)-Birnessite(-) hybrid. The as-constructed LDH(+)-Birnessite(-) hybrid catalyst showed advanced catalytic activity and excellent stability towards OER under a close to industrial hydrogen production condition (85 °C and 6 M KOH) for more than 20 h at the current densities larger than 100 mA cm -2 . Experimentally, we found that besides the enlarged interlayer distance, the flexible interlayer NiFe LDH(+) also modulates the electronic structure of layered MnO 2 , and creates an electric field between NiFe LDH(+) and Birnessite(-), wherein OER occurs with a greatly decreased overpotential. DFT calculations confirmed the interlayer LDH modulations of the OER process, attributable to the distinct electronic distributions and environments. Upshifting the Fe-3d orbitals in LDH promotes electron transfer from the layered MnO 2 to LDH, significantly boosting up the OER performance. This work opens a new way to fabricate highly efficient OER catalyst for industrial water oxidation., (© 2021 Wiley-VCH GmbH.)