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1. Oxo dicopper anchored on carbon nitride for selective oxidation of methane

   https://doi.org/10.1038/s41467-022-28987-1  

   Xie, Pengfei; Ding, Jing; Yao, Zihao; Pu, Tiancheng; Zhang, Peng; Huang, Zhennan; Wang, Canhui; Zhang, Junlei; Zecher-Freeman, Noah; Zong, Han; et al (December 2022, Nature Communications)

   Abstract Selective conversion of methane (CH 4 ) into value-added chemicals represents a grand challenge for the efficient utilization of rising hydrocarbon sources. We report here dimeric copper centers supported on graphitic carbon nitride (denoted as Cu 2 @C 3 N 4 ) as advanced catalysts for CH 4 partial oxidation. The copper-dimer catalysts demonstrate high selectivity for partial oxidation of methane under both thermo- and photocatalytic reaction conditions, with hydrogen peroxide (H 2 O 2 ) and oxygen (O 2 ) being used as the oxidizer, respectively. In particular, the photocatalytic oxidation of CH 4 with O 2 achieves >10% conversion, and >98% selectivity toward methyl oxygenates and a mass-specific activity of 1399.3 mmol g Cu −1 h −1 . Mechanistic studies reveal that the high reactivity of Cu 2 @C 3 N 4 can be ascribed to symphonic mechanisms among the bridging oxygen, the two copper sites and the semiconducting C 3 N 4 substrate, which do not only facilitate the heterolytic scission of C-H bond, but also promotes H 2 O 2 and O 2 activation in thermo- and photocatalysis, respectively. 

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2. A (2-(Pyrrolidin-1-yl)ethan-1-olate)(1-oxo-3-phenyl-1,4-dihydronaphthalen-2-olate) μ-Oxo-Bridged Dicopper(II) Dimeric Complex

   https://doi.org/10.3390/M1846  

   Artis, Rylan; Padgett, Clifford W; Musso, Kennedy; Shank, Nathaniel; Marks, Allison; Quillian, Brandon (September 2024, Molbank)

   The reaction of 2-(1H-pyrrol-1-yl)ethanol with 3-hydroxyflavone in the presence of copper(II) bromide yielded a dimeric copper(II) complex, [μ-O-(κ2-O,O-flav)(κ2-N,O-2PEO)Cu]2 (1) (flav = 3-hydroxyflavonolate; 2PEO = 2-(1H-pyrrol-1-yl)ethanolate) with both the flav and 2PEO ligands bound to the copper(II) atom in a κ2-bonding mode. The dimer is held electrostatically by bridging oxygen atoms between two copper atoms. Complex 1 was characterized by single-crystal X-ray diffraction, infrared, and UV-Vis spectroscopy, elemental analysis, and melting point determination. The complex crystallizes in the monoclinic space group P21/n (14) with cell values of a = 11.85340(10) Å, b = 8.51480(10) Å, c = 23.8453(2) Å; β = 99.3920(10)°. 

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3. Crystal structures of three copper(II)–2,2′-bipyridine (bpy) compounds, [Cu(bpy) ₂ (H ₂ O)][SiF ₆ ]·4H ₂ O, [Cu(bpy) ₂ (TaF ₆ ) ₂ ] and [Cu(bpy) ₃ ][TaF ₆ ] ₂ and a related coordination polymer, [Cu(bpy)(H ₂ O) ₂ SnF ₆ ] _n

   https://doi.org/10.1107/S2056989021000633  

   Nisbet, Matthew L.; Hiralal, Emily; Poeppelmeier, Kenneth R. (February 2021, Acta Crystallographica Section E Crystallographic Communications)

   null (Ed.)

   We report the hydrothermal syntheses and crystal structures of aquabis(2,2′-bipyridine-κ 2 N , N ′)copper(II) hexafluoridosilicate tetrahydrate, [Cu(bpy) 2 (H 2 O)][SiF 6 ]·4H 2 O (bpy is 2,2′-bipyridine, C 10 H 8 N 2 ), (I), bis(2,2′-bipyridine-3κ 2 N , N ′)-di-μ-fluorido-1:3κ 2 F : F ;2:3κ 2 F : F -decafluorido-1κ 5 F ,2κ 5 F -ditantalum(V)copper(II), [Cu(bpy) 2 (TaF 6 ) 2 ], (II), tris(2,2′-bipyridine-κ 2 N , N ′)copper(II) bis[hexafluoridotantalate(V)], [Cu(bpy) 3 ][TaF 6 ] 2 , (III), and catena -poly[[diaqua(2,2′-bipyridine-κ 2 N , N ′)copper(II)]-μ-fluorido-tetrafluoridotin-μ-fluorido], [Cu(bpy)(H 2 O) 2 SnF 6 ] n , (IV). Compounds (I), (II) and (III) contain locally chiral copper coordination complexes with C 2 , D 2 , and D 3 symmetry, respectively. The extended structures of (I) and (IV) are consolidated by O—H...F and O—H...O hydrogen bonds. The structure of (III) was found to be a merohedral (racemic) twin. 

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4. Ultrasmall Cu Nanoparticles Supported on Crystalline, Mesoporous ZnO for Selective CO ₂ Hydrogenation

   https://doi.org/10.1002/cctc.202301077  

   Hu, Mingzhen; Lu, Xingxu; Zhu, Chunxiang; Yang, Tiangang; Tan, Haiyan; Jin, Lei; Kerns, Peter; Meng, Michael; Suib, Steven L; Gao, Puxian; et al (February 2024, ChemCatChem)

   Abstract Converting CO₂to value‐added chemicals,e. g., CH₃OH, is highly desirable in terms of the carbon cycling while reducing CO₂emission from fossil fuel combustion. Cu‐based nanocatalysts are among the most efficient for selective CO₂‐to‐CH₃OH transformation; this conversion, however, suffers from low reactivity especially in the thermodynamically favored low temperature range. We herein report ultrasmall copper (Cu) nanocatalysts supported on crystalline, mesoporous zinc oxide nanoplate (Cu@mZnO) with notable activity and selectivity of CO₂‐to‐CH₃OH in the low temperature range of 200–250 °C. Cu@mZnO nanoplates are prepared based on the crystal‐crystal transition of mixed Cu and Zn basic carbonates to mesoporous metal oxides and subsequent hydrogen reduction. Under the nanoconfinement of mesopores in crystalline ZnO frameworks, ultrasmall Cu nanoparticles with an average diameter of 2.5 nm are produced. Cu@mZnO catalysts have a peak CH₃OH formation rate of 1.13 mol h⁻¹per 1 kg under ambient pressure at 246 °C, about 25 °C lower as compared to that of the benchmark catalyst of Cu−Zn−Al oxides. Our new synthetic strategy sheds some valuable insights into the design of porous catalysts for the important conversion of CO₂‐to‐CH₃OH. 

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5. Sustainedly High‐Rate Electroreduction of CO ₂ to Multi‐Carbon Products on Nickel Oxygenate/Copper Interfacial Catalysts

   https://doi.org/10.1002/aenm.202400827  

   Mao, Xuejiao; Chang, Chun‐Wai; Li, Zhiguo; Han, Zishan; Gao, Jiachen; Lyons, Mason; Sterbinsky, George; Guo, Yong; Zhang, Bo; Wang, Yaogang; et al (July 2024, Advanced Energy Materials)

   Abstract Copper (Cu) is the most attractive electrocatalyst for CO₂reduction to multi‐carbon (C₂₊) products with high economic value in considerable amounts. However, the rational design of a structurally stable Cu‐based catalyst that can achieve high activity and stability towards C₂₊products remain a grand challenge. Here, a highly stable nickel oxygenate/Cu electrocatalyst is developed with abundant NiOOH/Cu interfaces by in situ electrochemical reconstruction. The nickel oxygenate/Cu electrocatalyst achieves a superior Faradaic efficiency of 86.3 ± 3.0% and a record partial current density of 2085 A g⁻¹for C₂₊products with long‐term stability. In situ experimental and theoretical studies demonstrates that the exceptional performance in generating C₂₊products is attributed to the presence of the NiOOH/Cu interfaces which increase *CO coverage, lower energy barrier for *CO coupling and stabilize *OCCO simultaneously. This work provides new insights into the rational design of electrocatalysts to achieve stable and efficient electrocatalytic CO₂reduction capabilities. 

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