Post‐Nickelation of a Crystalline Trinuclear Copper Organic Framework for Synergistic Photocatalytic Carbon Dioxide Conversion

Abstract

Rational regulation of electronic structures and functionalities of framework materials still remains challenging. Herein, reaction of 4,4′,4′′‐nitrilo‐tribenzhydrazide with tris(μ2‐4‐carboxaldehyde‐pyrazolato‐N,N′)‐tricopper (Cu3Py3) generates the crystalline copper organic framework USTB‐11(Cu). Post‐modification with divalent nickel ions affords the heterometallic framework USTB‐11(Cu,Ni). Powder X‐ray diffraction and theoretical simulations reveal their two‐dimensional hexagonal structure geometry. A series of advanced spectroscopic techniques disclose the mixed CuI/CuII state nature of Cu3Py3 in USTB‐11(Cu,Ni) with a uniform bistable Cu34+(CuI2CuII) : Cu35+(CuICuII2) (ca. 1 : 3) oxidation state, resulting in a significantly improved formation efficiency of the charge‐separation state. This endows the Ni sites with enhanced activity and USTB‐11(Cu,Ni) with outstanding photocatalytic CO2 to CO performance with a conversion rate of 22 130 μmol g−1 h−1 and selectivity of 98 %.

Relative Local Electron Density Tuning in Metal‐Covalent Organic Frameworks for Boosting CO2Photoreduction

“…Likewise, the Cu 2p3/2 region provided Cu 2 + at about 935.08 eV and Cu 1 + at 933.06 eV for VL-MCOF-1. [21] As for g-C 34 N 6 -COF whose structure was similar to VL-MCOF-1 except that the Cu 3 -(PyCA) 3 core was replaced by triazine, was also synthesized to certificate that the Cu 3 (PyCA) 3 core of VL-MCOFs could act as potential ER units. The structure and morphology of g-C 34 N 6 -COF were also well characterized by PXRD, TGA, FI-IR, SEM and TEM tests (Figures S19-S24).…”

Gold(I)-Organic Frameworks as Catalysts for Carboxylation of Alkynes with CO2

“…Gold is a fascinating element and features unique properties including aurophilicity, luminescence, bioactivity, and catalytic activity that stands out from other transition metals, leading to exponentially increasing applications in chemistry, nanotechnology, material science, and medicine. , Particularly, gold­(I) complexes have been found to efficiently catalyze many useful carbon–carbon and carbon–heteroatom bond-forming processes . Meanwhile, metal–organic frameworks (MOFs) as a class of crystalline porous materials possess periodic and precise architecture and highly specific surface area as well as intriguing structural and functional diversity; thus, MOFs have been proved as promising platforms for wide applications in gas separation, energy storage, heterogeneous catalysis, and so on. − To integrate Au­(I) into MOFs, some methods like installation of gold nanoparticles into pores and anchoring gold complexes in skeleton have been demonstrated. − However, these approaches would decrease MOF porosity, and gold ions are unevenly dispersed, resulting in unsatisfactory performance. , In sharp contrast, constructing porous MOFs with gold­(I) nodes (Au-MOFs) not only preserve the porosity but also generate uniformly distributed gold sites . Therefore, the fabrication of Au-MOFs is highly desired yet has never been achieved.…”

Covalent organic frameworks embedding single cadmium sites for efficient carboxylative cyclization of CO2with propargylic amines

“…21 From a structural viewpoint, these diverse porous materials, with tunable nanoscale pores and high surface areas are expected to afford ideal candidates for CO 2 adsorption, diffusion, and activation. 22 Therefore, much attention has been paid to COFs research on CO 2 conversion including CO 2 photoreduction and chemical fixation over the past decade, [23][24][25][26][27][28][29] and considerable progress has been achieved. In particular, the molecular functionality of COFs by coordinating metal sites has been proven to be an efficient way to enhance catalytic activity due to the synergetic advantages of both heterogeneous and homogeneous catalysis.…”