Structurally Diverse Polynuclear Copper(I) Complexes Bridged by Pyrimidine-, Pyrazine-, and Triazine-based Ligands with Several 2-Pyridyl Groups

An Organic-Hybrid Zinc Iodocuprate with Bifunctional Catalytic Performance

The exploration of novel functional organic-hybrid heterometallic iodocuprates is of great significance for the potential photoelectric, photocatalytic, and electrocatalytic applications. Herein, a facile hydrothermal reaction of ZnO, CuI, CH3CN, and 2,4,6-tris-2-pyridyl-1,3,5-triazine (TPTZ) in an HI aqueous solution at 80 °C for 6 days yielded an organic-hybrid zinc iodocuprate [Zn2Cu2I6 (TPTZ)2]·H2O·CH3CN (ZnCuI-1). ZnCuI-1 shows a new type of tetranuclear heterometallic iodide based on the combination of one rhombohedral [Cu2I2] cluster and two organic-hybrid zinc iodide [ZnI2 (TPTZ)] units. ZnCuI-1 is first combined with a Ni nanoparticle and porous nickel foam (NF) to prepare a Ni/ZnCuI-1/NF electrode as an efficient electrocatalyst, which exhibits remarkable hydrogen evolution reaction activity with a low overpotential of 109 mV at 10 mA·cm-2. Because the absorption edge of ZnCuI-1 is 1.48 eV and lies in the visible-light energy range for the suitable harvesting ability, ZnCuI-1 exhibits excellent photocurrent response and striking visible-light-driven photocatalytic activity for the degradation of methylene blue. This work broadens the applied range of organic-hybrid heterometallic iodocuprates, offering the potential alternative materials for photoelectric, photocatalytic, and electrocatalytic applications.

Structural diversity of copper(I)-ethylene complexes with 2,4-bis(2-pyridyl)pyrimidine directed by anions

The 3 : 1 reaction of [Cu(C2H4)n]ClO4 with 2,4-bis(2-pyridyl)pyrimidine (bpprd) in Me2CO under C2H4 afforded yellow prism crystals of the dinuclear Cu(I)-C2H4 complex [Cu2(bpprd)(η2-C2H4)2(ClO4)2] (1). The 3 : 1 reaction of [Cu(C2H4)n]NO3 with bpprd in Me2CO under C2H4 afforded yellow plate crystals of the tetranuclear Cu(I)-C2H4 complex [Cu4(bpprd)2(η2-C2H4)4(μ-NO3)2](NO3)2 (2). The 10 : 1 reaction of [Cu(C2H4)n]BF4 with bpprd in Me2CO under C2H4 afforded yellow plate crystals of the dinuclear Cu(I)-C2H4 complex [Cu2(bpprd)(η2-C2H4)2(BF4)]BF4 (3). The 3 : 1 reaction of [Cu(C2H4)n]BF4 with bpprd in Me2CO under C2H4 afforded red prism crystals of the polymeric Cu(I)-C2H4 complex {[Cu6(bpprd)4(η2-C2H4)2(μ-η2:η2-C2H4)(μ-BF4)2](BF4)4}n (4). The X-ray crystal structures of complexes 1-4 have been determined. The structural diversity of Cu(I)-C2H4 complexes bridged by bpprd with different anions was demonstrated. The 1D Cu(I)-bpprd/C2H4 coordination polymer 4 bridged by unusual μ-η2:η2-C2H4 and the μ-BF4- anion is of particular significance. Complex 1 exhibited relatively well-resolved 1H NMR signals of bpprd and C2H4 (δ = 4.97 ppm) in (CD3)2CO at 23 °C.