Macroscopic Architecture of Charge Transfer-Induced Molecular Recognition from Electron-Rich Polymer Interpenetrated Porous Frameworks

Fluorescent and electron-rich polymer threaded into porous framework provides a scaffold for sensing acceptor molecules through noncovalent interactions. Herein, poly­(9-vinylcarbazole) (PVK) threaded MIL-101 with confined nanospace was synthesized by vinyl-monomer impregnation, in situ polymerization, and interpenetration. The pore size of the resulted hybrid could be controlled by varying the time of polymerization and interpenetration. The interaction of PVK-threaded MIL-101 with guest molecules showed a charge-transfer progress with an obvious red shift in the optical spectra. Depending on the degree of the interaction, the solution color changed from blue to green or to yellow. In particular, electron-rich PVK-threaded MIL-101 could effectively probe electron-poor nitro compounds, especially 1,3,5-trinitrobenzene (TNP), a highly explosive material. This sensing approach is a colorimetric methodology, which is very simple and convenient for practical analysis and operation

Synthesis, Characterization and Ethylene Oligomerization Studies of Nickel Complexes Bearing 2-Benzimidazolylpyridine Derivatives

A series of nickel complexes ligated by 2-(2-benzimidazole)-6-methylpyridine, 2-(1-methyl-2-benzimidazole)-6-acetylpyridine, and 2-(1-methyl-2-benzimidazole)-6-(1-aryliminoethyl)pyridine was synthesized and examined by IR spectroscopic and elemental analysis. Their molecular structures were determined by single-crystal X-ray diffraction analysis. On activation with diethylaluminum chloride (Et2AlCl), all the nickel complexes exhibited good catalytic activities for ethylene oligomerization, and the nickel(II) complexes bearing 2-(1-methyl-2-benzimidazole)-6-(1-aryliminoethyl)pyridines showed good activities up to 5.87 × 105 g mol-1(Ni) h-1 atm-1. The various reaction parameters were investigated in detail, and the results revealed that both the steric and electronic effects of ligands strongly affect the catalytic activities of their nickel complexes as well as different coordination style

[4 + 2] Cycloaddition Reaction To Approach Diazatwistpentacenes: Synthesis, Structures, Physical Properties, and Self-assembly

Three novel diazatwistpentacenes (1,4,6,13-tetraphenyl-7:8,11:12-bisbenzo-2,3-diazatwistpentacene (<b>1</b>, IUPAC name: 9,11,14,16-tetraphenyl-1,6-dihydrobenzo­[8,9]­triphenyleno­[2,3-<i>g</i>]­phthalazine); 1,4-di­(pyridin-2-yl)-6,13-diphenyl-7:8,11:12-bisbenzo-2,3-diazatwistpentacene (<b>2</b>, IUPAC name: 9,16-diphenyl-11,14-di­(pyridin-2-yl)-1,6-dihydrobenzo­[8,9]­triphenyleno­[2,3-<i>g</i>]­phthalazine); and 1,4-di­(thien-2-yl)-6,13-diphenyl-7:8,11:12-bisbenzo-2,3-diazatwistpentacene (<b>3</b>, IUPAC name: 9,16-diphenyl-11,14-di­(thien-2-yl)-1,6-dihydrobenzo­[8,9]­triphenyleno­[2,3-<i>g</i>]­phthalazine)) have been successfully synthesized through [4 + 2] cycloaddition reaction involving <i>in situ</i> arynes as dienophiles and substituted 1,2,4,5-tetrazines as dienes. Their structures have been determined by single-crystal X-ray diffraction, confirming that all compounds have twisted configurations with torsion angles between the pyrene unit and the 2,3-diazaanthrance part as high as 21.52° (for <b>1</b>), 24.74° (for <b>2</b>), and 21.14° (for <b>3</b>). The optical bandgaps for all compounds corroborate the values derived from CV. The calculation done by DFT shows that the HOMO–LUMO bandgaps are in good agreement with experimental data. Interestingly, the substituted groups (phenyl, pyridyl, thienyl) in the 1,4-positions did affect their self-assembly and the optical properties of as-resulted nanostructures. Under the same conditions, compounds <b>1</b>–<b>3</b> could self-assemble into different morphologies such as microrods (for <b>1</b>), nanoprisms (for <b>2</b>), and nanobelts (for <b>3</b>). Moreover, the UV–vis absorption and emission spectra of as-prepared nanostructures were largely red-shifted, indicating J-type aggregation for all materials. Surprisingly, both <b>1</b> and <b>2</b> showed aggregation-induced emission (AIE) effect, while compound <b>3</b> showed aggregation-caused quenching (ACQ) effect. Our method to approach novel twisted azaacenes through [4 + 2] reaction could offer a new tool to develop unusual twisted conjugated materials for future optoelectronic applications

Heteroleptic Dipyrrinato Complexes Containing 5‑Ferrocenyldipyrromethene and Dithiocarbamates as Coligands: Selective Chromogenic and Redox Probes

Six heteroleptic dipyrrinato complexes [Ni­(fcdpm)­(dedtc)] (<b>1</b>), [Ni­(fcdpm)­(dipdtc)] (<b>2</b>), [Ni­(fcdpm)­(dbdtc)] (<b>3</b>), [Pd­(fcdpm)­(dedtc)] (<b>4</b>), [Pd­(fcdpm)­(dipdtc)] (<b>5</b>), and [Pd­(fcdpm)­(dbdtc)] (<b>6</b>) (fcdpm = 5-ferrocenyldipyrromethene; dedtc = diethyldithiocarbamate; dipdtc = diisopropyldithiocarbamate; dbdtc = dibutyldithiocarbamate) have been synthesized and characterized by elemental analyses and spectral (ESI-MS, IR, ¹H, ¹³C NMR, UV–vis) and electrochemical studies. Crystal structures of <b>1</b>, <b>2</b>, <b>4</b>, and <b>5</b> have been authenticated by X-ray single-crystal analyses. Nickel-based complexes <b>1</b>–<b>3</b> display selective chromogenic and redox sensing for Hg²⁺ and Pb²⁺ ions, while palladium complexes <b>4</b>–<b>6</b> display selective chromogenic and redox sensing only for Hg²⁺. Electronic absorption, ESI-MS, and electrochemical studies indicated that sensing arises from interaction between <b>1</b>–<b>3</b> and Hg²⁺/Pb²⁺ through sulfur of the coordinated dithiocarbamates, while it arises from the pyrrolic nitrogen of fcdpm and dithiocarbamate sulfur from <b>4</b>–<b>6</b> and Hg²⁺. Different modes of binding between Ni and Pd complexes have further been supported by theoretical studies. The receptor–cation binding constants (<i>K</i>_a) and stoichiometry between probes and Hg²⁺/Pb²⁺ have been estimated by the Benesi–Hildebrand method and Job’s plot analysis. Detection limits for <b>1</b>–<b>3</b> toward Hg²⁺/Pb²⁺ and <b>4</b>–<b>6</b> for Hg²⁺ have been found to be reasonably high

Surfactant-Thermal Syntheses, Structures, and Magnetic Properties of Mn–Ge–Sulfides/Selenides

Although either surfactants or amines have been investigated to direct the crystal growth of metal chalcogenides, the synergic effect of organic amines and surfactants to control the crystal growth has not been explored. In this report, several organic bases (hydrazine monohydrate, ethylenediamine (<i>en</i>), 1,2-propanediamine (1,2-<i>dap</i>), and 1,3-propanediamine (1,3-<i>dap</i>)) have been employed as structure-directing agents (SDAs) to prepare four novel chalcogenides (Mn₃Ge₂S₇(NH₃)₄ (<b>1</b>), [Mn­(en)₂(H₂O)]­[Mn­(en)₂MnGe₃Se₉] (<b>2</b>), (1,2-dapH)₂­{[Mn­(1,2-dap)₂]­Ge₂Se₇} (<b>3</b>), and (1,3-dapH)­(puH)­MnGeSe₄(<b>4</b>) (pu = propyleneurea) under surfactant media (PEG-400). These as-prepared new crystalline materials provide diverse metal coordination geometries, including MnS₃N tetrahedra, MnGe₂Se₇ trimer, and MnGe₃Se₁₀ T2 cluster. Compounds <b>1</b>–<b>3</b> have been fully characterized by single-crystal X-ray diffraction (XRD), powder XRD, UV–vis spectra, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Moreover, magnetic measurements for compound <b>1</b> showed an obvious antiferromagnetic transition at ∼9 K. Our research not only enriches the structural chemistry of the transitional-metal/14/16 chalcogenides but also allows us to better understand the synergic effect of organic amines and surfactants on the crystallization of metal chalcogenides

Surfactant-Thermal Syntheses, Structures, and Magnetic Properties of Mn–Ge–Sulfides/Selenides

Although either surfactants or amines have been investigated to direct the crystal growth of metal chalcogenides, the synergic effect of organic amines and surfactants to control the crystal growth has not been explored. In this report, several organic bases (hydrazine monohydrate, ethylenediamine (<i>en</i>), 1,2-propanediamine (1,2-<i>dap</i>), and 1,3-propanediamine (1,3-<i>dap</i>)) have been employed as structure-directing agents (SDAs) to prepare four novel chalcogenides (Mn₃Ge₂S₇(NH₃)₄ (<b>1</b>), [Mn­(en)₂(H₂O)]­[Mn­(en)₂MnGe₃Se₉] (<b>2</b>), (1,2-dapH)₂­{[Mn­(1,2-dap)₂]­Ge₂Se₇} (<b>3</b>), and (1,3-dapH)­(puH)­MnGeSe₄(<b>4</b>) (pu = propyleneurea) under surfactant media (PEG-400). These as-prepared new crystalline materials provide diverse metal coordination geometries, including MnS₃N tetrahedra, MnGe₂Se₇ trimer, and MnGe₃Se₁₀ T2 cluster. Compounds <b>1</b>–<b>3</b> have been fully characterized by single-crystal X-ray diffraction (XRD), powder XRD, UV–vis spectra, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Moreover, magnetic measurements for compound <b>1</b> showed an obvious antiferromagnetic transition at ∼9 K. Our research not only enriches the structural chemistry of the transitional-metal/14/16 chalcogenides but also allows us to better understand the synergic effect of organic amines and surfactants on the crystallization of metal chalcogenides

Surfactant-Thermal Syntheses, Structures, and Magnetic Properties of Mn–Ge–Sulfides/Selenides

Although either surfactants or amines have been investigated to direct the crystal growth of metal chalcogenides, the synergic effect of organic amines and surfactants to control the crystal growth has not been explored. In this report, several organic bases (hydrazine monohydrate, ethylenediamine (<i>en</i>), 1,2-propanediamine (1,2-<i>dap</i>), and 1,3-propanediamine (1,3-<i>dap</i>)) have been employed as structure-directing agents (SDAs) to prepare four novel chalcogenides (Mn₃Ge₂S₇(NH₃)₄ (<b>1</b>), [Mn­(en)₂(H₂O)]­[Mn­(en)₂MnGe₃Se₉] (<b>2</b>), (1,2-dapH)₂­{[Mn­(1,2-dap)₂]­Ge₂Se₇} (<b>3</b>), and (1,3-dapH)­(puH)­MnGeSe₄(<b>4</b>) (pu = propyleneurea) under surfactant media (PEG-400). These as-prepared new crystalline materials provide diverse metal coordination geometries, including MnS₃N tetrahedra, MnGe₂Se₇ trimer, and MnGe₃Se₁₀ T2 cluster. Compounds <b>1</b>–<b>3</b> have been fully characterized by single-crystal X-ray diffraction (XRD), powder XRD, UV–vis spectra, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Moreover, magnetic measurements for compound <b>1</b> showed an obvious antiferromagnetic transition at ∼9 K. Our research not only enriches the structural chemistry of the transitional-metal/14/16 chalcogenides but also allows us to better understand the synergic effect of organic amines and surfactants on the crystallization of metal chalcogenides

Impermeable Inorganic Walls Sandwiching Photoactive Layer toward Inverted Perovskite Solar and Indoor-Photovoltaic Devices

Interfaces between the perovskite active layer and the charge-transport layers (CTLs) play a critical role in both efficiency and stability of halide-perovskite photovoltaics. One of the major concerns is that surface defects of perovskite could cause detrimental nonradiative recombination and material degradation. In this work, we addressed this challenging problem by inserting ultrathin alkali-fluoride (AF) films between the tri-cation lead-iodide perovskite layer and both CTLs. This bilateral inorganic walls strategy makes use of both physical-blocking and chemical-anchoring functionalities of the continuous, uniform and compact AF framework: on the one hand, the uniformly distributed alkali-iodine coordination at the perovskite-AF interfaces effectively suppresses the formation of iodine-vacancy defects at the surfaces and grain boundaries of the whole perovskite film, thus reducing the trap-assisted recombination at the perovskite-CTL interfaces and therewith the open-voltage loss; on the other hand, the impermeable AF buffer layers effectively prevent the bidirectional ion migration at the perovskite-CTLs interfaces even under harsh working conditions. As a result, a power-conversion efficiency (PCE) of 22.02% (certified efficiency 20.4%) with low open-voltage deficit (< 0.4V) was achieved for the low-temperature processed inverted planar perovskite solar cells. Exceptional operational stability (500 h, ISOS-L-2) and thermal stability (1000 h, ISOS-D-2) were obtained. Meanwhile, a 35.7% PCE was obtained under dim-light source (1000 lux white LED light) with the optimized device, which is among the best records in perovskite indoor photovoltaics

Surfactant Media To Grow New Crystalline Cobalt 1,3,5-Benzenetricarboxylate Metal–Organic Frameworks

In this report, three new metal–organic frameworks (MOFs), [Co₃(μ₃-OH)­(HBTC)­(BTC)₂Co­(HBTC)]·(HTEA)₃·H₂O (<b>NTU-Z30</b>), [Co­(BTC)]·HTEA·H₂O (<b>NTU-Z31</b>), [Co₃(BTC)₄]·(HTEA)₄ (<b>NTU-Z32</b>), where H₃BTC = 1,3,5-benzenetricarboxylic acid, TEA = triethylamine, and NTU = Nanyang Technological University, have been successfully synthesized under surfactant media and have been carefully characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis, and IR spectromtry. <b>NTU-Z30</b> has an unusual trimeric [Co₃(μ₃-OH)­(COO)₇] secondary building unit (SBU), which is different from the well-known trimeric [Co₃O­(COO)₆] SBU. The topology studies indicate that <b>NTU-Z30</b> and <b>NTU-Z32</b> possess two new topologies, 3,3,6,7-c net and 2,8-c net, respectively, while <b>NTU-Z31</b> has a known topology <b>rtl</b> type (3,6-c net). Magnetic analyses show that all three materials have weak antiferromagnetic behavior. Furthermore, <b>NTU-Z30</b> has been selected as the heterogeneous catalyst for the aerobic epoxidation of alkene, and our results show that this material exhibits excellent catalytic activity as well as good stability. Our success in growing new crystalline cobalt 1,3,5-benzenetricarboxylate MOFs under surfactant media could pave a new road to preparing new diverse crystalline inorganic materials through a surfactant-thermal method