Electroreduction of carbon dioxide (CO2) into high‐value and readily collectable liquid products is vital but remains a substantial challenge due to the lack of highly efficient and robust electrocatalysts. Herein, Bi‐based metal‐organic framework (CAU‐17) derived leafy bismuth nanosheets with a hybrid Bi/BiO interface (Bi NSs) is developed, which enables CO2 reduction to formic acid (HCOOH) with high activity, selectivity, and stability. Specially, the flow cell configuration is employed to eliminate the diffusion effect of CO2 molecules and simultaneously achieve considerable current density (200 mA cm−2) for industrial application. The faradaic efficiency for transforming CO2 to HCOOH can achieve over 85 or 90% in 1 m KHCO3 or KOH for at least 10 h despite a current density that exceeds 200 mA cm−2, outperforming most of the reported CO2 electroreduction catalysts. The hybrid Bi/BiO surface of leafy bismuth nanosheets boosts the adsorption of CO2 and protects the surface structure of the as‐prepared leafy bismuth nanosheets, which benefits its activity and stability for CO2 electroreduction. This work shows that modifying electrocatalysts by surface oxygen groups is a promising pathway to regulate the activity and stability for selective CO2 reduction to HCOOH.

The electroreduction of carbon dioxide is a promising strategy to synthesize value‐added feedstocks and realize carbon neutralization. Copper catalysts are well‐known to be active for selective electroreduction of CO2 to multicarbon products, although the role played by the surface architecture is not fully understood. Herein, mesoporous Cu nanoribbons are constructed via in‐situ electrochemical reduction of Cu based metal organic frameworks for the highly selective synthesis of C2+ chemicals. With the mesoporous structure, a high C2+ Faradaic efficiency of 82.3% with a partial current density of 347.9 mA cm−2 is achieved in a flow‐cell electrolyzer. Controlled electroreduction of CO2 with Cu nanoribbons exhibited clearly greater selectivity towards C2+ products than Cu nanoleaves and Cu nanorods without porous structures. Finite difference time domain results indicate that the mesoporous structure can enhance the electric field on the catalyst surface, which increases the concentration of K+ and OH−, thus allowing the authors to promote CO2 reduction pathways towards C2+ products.

Bimetallic MIL-101(Al/Fe)–NH2 exhibits enhanced acid–base bifunctional catalytic activity due to its synergistic mechanism and hierarchical pore system.

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Double-shelled hollow mesoporous silica nanospheres as an acid–base bifunctional catalyst for cascade reactions.

Metal−organic framework (MOF)-supported macroscale resin catalysts, IRA900(xOH)-MIL-101(Al)−NH 2 (x means the concentration of NaOH), with spatially isolated antagonistic acid−base active sites were successfully synthesized through a novel strategy by ion exchange and in situ solvothermal methods. The hierarchical pore system of the as-prepared catalysts effectively promotes the mass transfer and contacts with catalytic active centers during the organic reactions. Therefore, the environmentally friendly catalysts exhibit excellent superior activity and stability in one-pot deacetalization−Knoevenagel condensation reaction, and the yield by optimal IRA900(0.2OH)-MIL-101(Al)−NH 2 reaches close to 99% after 5 h at 110 °C. Thanks to the millimeter-sized resin carrier and robust sphere morphology, the recycling of the as-prepared catalysts only requires natural sedimentation. This work presents an effective strategy to build low-toxic acid−base catalysts by combining the advantages of ionexchange resins and functionalized MOF materials.

Unchelated scandium(III) trichloride complexes, 2-(ArNCH)C 6 H 4 Me 4 CpScCl 3 Li(THF) 4 (Ar = 2,6-i Pr 2 C 6 H 3 (1a), 2,6-Et 2 C 6 H 3 (1b), 2,6-Me 2 C 6 H 3 (1c)), were obtained from the reaction of ScCl 3 (THF) 3 with the lithium salt of the corresponding ligand, 2-(ArC 6 H 3 N CH)C 6 H 4 Me 4 CpLi, in THF. After heating at 120 °C under vacuum for 30 min, the attached LiCl and THF were removed from complexes 1 to give the chelated scandium(III) dichloride complexes 2-(ArNCH)C 6 H 4 Me 4 CpScCl 2 ([Ar = 2,6-i Pr 2 C 6 H 3 (2a), 2,6-Et 2 C 6 H 3 (2b), 2,6-Me 2 C 6 H 3 (2c)). Attempts to synthesize dialkyl scandium(III) complexes by the reaction of Sc(CH 2 SiMe 3 ) 3 (THF) 2 with the corresponding free ligands were not successful. The scandium(III) trialkyl complex 2-[Li(THF) 3 (2,6-i Pr 2 C 6 H 3 )NCH]C 6 H 4 Me 4 CpSc-(CH 2 SiMe 3 ) 3 (3) was synthesized by a one-pot reaction of ScCl 3 (THF) 3 with 2-(2,6-i Pr 2 C 6 H 3 NCH)C 6 H 4 Me 4 CpLi and 3 equiv of Me 3 SiCH 2 Li in THF sequentially. The scandium(III) dialkyl complex 2-(2,6-i Pr 2 C 6 H 3 NCH)C 6 H 4 Me 4 CpSc-(CH 2 SiMe 3 ) 2 ( 4) was obtained from the reaction of the dichloride complex 2a with 2 equiv of Me 3 SiCH 2 Li in hexane. Complexes 1b,c were directly converted to complexes 2b,c without purification and characterization. All other scandium(III) complexes were characterized by 1 H and 13 C NMR spectroscopy and elemental analyses. The structures of complexes 1a, 2c, 3, and 4 were determined by single-crystal X-ray crystallography, which indicates that the imine N atoms in complexes 1a and 3 do not coordinate to the central scandium atoms. Complexes 2a−c and 4 were found to exhibit moderate catalytic activity for propylene and 1-hexene polymerization upon activation with AlR 3 /Ph 3 CB(C 6 F 5 ) 4 or methylaluminoxane (MAO) and produce atactic polypropylene and isotactic poly(1-hexene). The effects of molecular structures and reaction conditions on the catalytic behavior of these complexes were examined and the possible catalytic mechanism was discussed.