Self-Assembly of Polyhedral Indium–Organic Nanocages

A synthetic strategy to construct discrete indium–organic polyhedra has been illustrated based on small three-membered windows from a 2,5-pyridinedicarboxylate (PDC) ligand with an angle of 120°. [Et₂NH₂]₆[In₆(PDC)₁₂] (<b>InOF-10</b>) is a high-symmetry octahedron with eight three-membered windows, and [Et₂NH₂]₁₈[In₁₈(BPDC)₆(PDC)₃₀] (<b>InOF-11</b>) is a complex polyhedron derived from 3-edge-removed octahedra with an auxiliary biphenyl-3,3′-dicarboxylate (BPDC) ligand. Moreover, the sorption behavior of the latter is also well investigated

CuO Nanorod Arrays Shelled with Amorphous NiFe Layered Double Hydroxide Film for Enhanced Electrocatalytic Water Oxidation Activity

Recently, extensive efforts have been focused on CuO materials as the non-noble metal electrocatalysts for the oxygen evolution reaction (OER). However, their catalytic efficiency is still far from meeting the need of practical large-scale water splitting because of poor electrical conductivity and limited exposed active sites. Herein, we report that amorphous NiFe layered double hydroxide film can be grown on CuO nanorod arrays supported on Cu foil (NiFe-LDH/CuO NRs/CF) to construct a core–shell heterostructure via a facile electrochemical deposition approach. The resulting core–shell heterostructure demonstrates excellent OER performance in 1 M KOH, only requiring a small overpotential of 290 mV to drive the current density of 50 mV cm^–2 with a low Tafel slope of 60 mV dec^–1, and maintaining a steady current density of 50 mA cm^–2 for at least 35 h with negligible decline in catalytic activity, which is the best OER performance among reported CuO electrocatalysts to date. Remarkably, this catalytic performance is also superior to that of the state-of-the-art IrO₂ catalyst. The prominent catalytic performance of NiFe-LDH/CuO NRs could be attributed to the synergistic effect between NiFe-LDH film and CuO NRs. As a result, our research indicates that the construction of amorphous heterostructures could be a promising strategy for development of efficient OER systems

Thiacalix[4]arene-Supported Kite-Like Heterometallic Tetranuclear Zn^IILn^III₃ (Ln = Gd, Tb, Dy, Ho) Complexes

Four kite-like tetranuclear Zn^IILn^III₃ (Ln= Gd <b>1</b>, Tb <b>2</b>, Dy <b>3</b>, Ho <b>4</b>) clusters supported by <i>p</i>-<i>tert</i>-butylthiacalix­[4]­arene (H₄BTC4A) have been prepared under solvothermal conditions and structurally characterized by single crystal X-ray diffraction and powder X-ray diffraction (PXRD). In the structures of these four complexes, each of them is capped by two tail-to-tail <i>p</i>-<i>tert</i>-butylthiacalix­[4]­arene molecules to form a bent sandwich-like unit. The photoluminescent analyses reveal that the H₄BTC4A is an efficient sensitizer for Tb³⁺ ions in <b>2</b>. The magnetic properties of complexes <b>1</b>–<b>4</b> are also investigated, in which complex <b>3</b> exhibits slow magnetization relaxation typical for single molecule magnets

Thiacalix[4]arene-Supported Kite-Like Heterometallic Tetranuclear Zn^IILn^III₃ (Ln = Gd, Tb, Dy, Ho) Complexes

Four kite-like tetranuclear Zn^IILn^III₃ (Ln= Gd <b>1</b>, Tb <b>2</b>, Dy <b>3</b>, Ho <b>4</b>) clusters supported by <i>p</i>-<i>tert</i>-butylthiacalix­[4]­arene (H₄BTC4A) have been prepared under solvothermal conditions and structurally characterized by single crystal X-ray diffraction and powder X-ray diffraction (PXRD). In the structures of these four complexes, each of them is capped by two tail-to-tail <i>p</i>-<i>tert</i>-butylthiacalix­[4]­arene molecules to form a bent sandwich-like unit. The photoluminescent analyses reveal that the H₄BTC4A is an efficient sensitizer for Tb³⁺ ions in <b>2</b>. The magnetic properties of complexes <b>1</b>–<b>4</b> are also investigated, in which complex <b>3</b> exhibits slow magnetization relaxation typical for single molecule magnets

Thiacalix[4]arene-Supported Kite-Like Heterometallic Tetranuclear Zn^IILn^III₃ (Ln = Gd, Tb, Dy, Ho) Complexes

Four kite-like tetranuclear Zn^IILn^III₃ (Ln= Gd <b>1</b>, Tb <b>2</b>, Dy <b>3</b>, Ho <b>4</b>) clusters supported by <i>p</i>-<i>tert</i>-butylthiacalix­[4]­arene (H₄BTC4A) have been prepared under solvothermal conditions and structurally characterized by single crystal X-ray diffraction and powder X-ray diffraction (PXRD). In the structures of these four complexes, each of them is capped by two tail-to-tail <i>p</i>-<i>tert</i>-butylthiacalix­[4]­arene molecules to form a bent sandwich-like unit. The photoluminescent analyses reveal that the H₄BTC4A is an efficient sensitizer for Tb³⁺ ions in <b>2</b>. The magnetic properties of complexes <b>1</b>–<b>4</b> are also investigated, in which complex <b>3</b> exhibits slow magnetization relaxation typical for single molecule magnets

Constructing Crystalline Heterometallic Indium–Organic Frameworks by the Bifunctional Method

In this work, we systematically report four indium–organic framework (InOF) crystals, which comprise the In­(CO₂)₄ monomer for [InCu­(inc)₄]­(NO₃) (<b>InOF-5</b>) and [Me₂NH₂]₂[In₂(Cu₄I₄)­(pdc)₄] (<b>InOF</b>-<b>6</b>), the In­(OH)­(CO₂)₂ chain for [In₂(Cu₄I₄)­(OH)₂(nia)₄] (<b>InOF-7</b>), and In₃O­(CO₂)₆ clusters for [(In₃O)₂(Cu₄I₄)₃(nia)₁₂(H₂O)₆]­(NO₃)₂ (<b>InOF-8</b>). With the help of the ligand-oriented bifunctional method, a series of novel heterometallic indium–organic frameworks can be easily achieved through the way the pyridyl N-affinitive sites connect to Cu-based units and the COO^–-affinitive sites to In­(III) centers. This new strategy will open the door to the construction of multifunctional and heterometallic InOF materials

Robust Cage-Based Zinc–Organic Frameworks Derived Dual-Doped Carbon Materials for Supercapacitor

Electrochemical double layer capacitors can store electrical energy by accumulating electrolyte ions on the electrode surface and are playing an important role in renewable energy sources due to their high power density and superior durability. Owing to the excellent electrical, mechanical, and thermal characteristics, three-dimensional multiporous carbon nanomaterials are catching considerable attention which could lead to the high-rate supercapacitor performance. Here, we present a stable 1.7 nm cage-based metal–organic framework (<b>BMM-9</b>, [Zn₂(TPO)_4/3(dabco)·Solvent]) with high porosity of 62.4%. On the other hand, after the thermal treatment at high temperature, the three-dimensional MOF-derived micro/mesoporous carbon material <b>BMM-9-900</b> acts as dual-doped active electrode materials and shows a capacitance of 182.8 F g^–1 at a current density of 1 A g^–1, and a capacity retention of 98.5% over 1000 cycles. Given the well-established structural tunability, these outcomes will shed light on a new generation of MOF-derived supercapacitors whose active materials can be tunable at the molecular level

Open Pentameric Calixarene Nanocage

A novel open helmetlike coordination cage has been synthesized based on Co₄-calixarene shuttlecock-like secondary building units and in situ generated phosphate anions, where the opening of the cage comprises a large 16-membered ring. The above unprecedented Co₂₀ nanocage presents the first pentameric calixarene coordination compound. Sorption behavior and magnetic properties are also investigated

High CO₂ Uptake Capacity and Selectivity in a Fascinating Nanotube-Based Metal–Organic Framework

An unusual porous metal–organic framework has been synthesized by using Pb­(II) and rigid V-shaped 4,4′-(pyri­dine-3,5-diyl)­diiso­phthalic acid (H₄L). Structure analysis reveals that there exist 1D cylindrical 14.26 Å and triangular prism 10.69 × 10.69 × 10.69 ų nanotubes in the framework. Gas sorption behavior of the nanoporous MOF shows a relatively high capacity and selectivity of CO₂ over CH₄

Low-Pressure Selectivity, Stepwise Gas Sorption Behaviors, and Luminescent Properties (Experimental Findings and Theoretical Correlation) of Three Zn(II)-Based Metal–Organic Frameworks

In this report, three new luminescent metal–organic frameworks (LMOFs), [Zn­(L1)₂]·CH₃CN (<b>1</b>), [Zn­(L1)₂] (<b>2</b>), and [Zn­(L1)­(L2)_0.5]·NMP (<b>3</b>) (HL1 = 6-aminonicotinic acid; H₂L2 = terephthalic acid; and NMP = <i>N</i>-methyl-2-pyrrolidone), have been solvothermally synthesized based on d¹⁰ metal ion Zn­(II) and free organic ligands (HL1 and H₂L2) in different solvent systems, all of which have been fully characterized. Single crystal data reveal that <b>1</b> and <b>2</b> are two 2D isomeride but with different space groups, which is caused by the different solvent systems during the synthesis procedure. The introduction of the bridging ligand H₂L2 in the solvent system of <b>2</b> produces <b>3</b> with the 3D microporous framework. The gas sorption exploration of <b>3</b> shows an interesting stepwise gas sorption behavior and attractive low-pressure selectivity between CO₂ and CH₄, which may be used as a potential material to separate the CO₂ from the natural gas. In addition, the luminescent properties of the free ligands and <b>1</b>–<b>3</b> have been investigated carefully, and the luminescent mechanisms have also been verified by the DFT calculation of HOMO, LUMO, and HOMO–LUMO gaps of free ligands and <b>1</b>–<b>3</b>