Three supramolecular compounds based on 1,4-benzeneditetrazole (H2BDT), (NH4)2(BDT) (1), Mg(H2O)6(HBDT)2·2H2O (2), and Mg(CH3OH)4(H2O)2(HBDT)2·2CH3OH (3) have been solvothermally synthesized and ...structurally characterized by single-crystal/powder X-ray diffraction. Structural analyses indicated that these compounds are 3D supramolecular structures stabilized by electrostatic interactions and intermolecular hydrogen bonds. The crystal to crystal transformation between 2 and 3 were investigated. The result showed that 2 is readily transform to 3 after immersed in methanol solution, while 3 can not be converted to 2 after immersed in distilled water solution.
Three supramolecular compounds based on 1,4-benzeneditetrazole (H2BDT) have been successfully assembled. They are 3D supramolecular structures stabilized by electrostatic interactions and intermolecular hydrogen bonds. Interestingly, compound 2 can be successfully transformed to 3 after immersed in methanol solution. Display omitted
•Three supramolecular compounds of 1,4-benzeneditetrazole have been assembled.•Their crystal structures have been determined by X-ray diffraction approach.•Crystal to crystal transformation between them has been successfully realized.
This review summarizes recent advances in the construction of stable MOFs, involving main group metal-carboxylate frameworks, transition metal-carboxylate frameworks, transition metal-azolate ...frameworks, rare earth metal-carboxylate frameworks, as well as post-synthetic MOFs. Furthermore, the PEC water splitting of some stable MOFs and MOF-based composites are discussed.
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•The construction of stable MOF-based materials has been introduced.•Stable MOF-based materials for PEC water splitting have been reviewed.•The correlation of catalytic performance and structure of MOF-based materials has been analyzed and discussed.•A perspective on MOF-based materials for PEC water splitting has been given.
Photoelectrochemical (PEC) water splitting into H2 and O2 has been regarded as a promising strategy to achieve solar-to-chemical energy conversion. Metal-organic frameworks (MOFs) are emerging as promising photoelectrocatalysts for this significant energy conversion reaction owing to their unique photochemical and textural properties. In this review, we summarized recent advances in the construction of stable MOFs for PEC water splitting, involving main group metal-carboxylate frameworks, transition metal-carboxylate frameworks, transition metal-azolate frameworks, rare earth metal-carboxylate frameworks, as well as post-synthetic MOFs. We particularly analyzed and discussed the correlation between catalytic performance and catalyst structures, based on which, we put forward a perspective for construction of efficient MOFs for PEC water splitting.
Invited for this month's cover is the group of Prof. Tong‐Bu Lu at Sun Yat‐Sen University/Tianjin University of Technology. The Cover picture depicts a beautiful lady, an imaginary figure of a forest ...fairy, praying with an Earth‐like crystal ball that is filled with cobalt complexes, aiming to realize the transformation of atmospheric CO2 to CO The Full Paper itself is available at 10.1002/cssc.201702280.
“The Cover picture depicts a beautiful lady…” This and more about the story behind the research that inspired the Cover image is presented in the Cover Profile. Read the full text of the corresponding research at 10.1002/cssc.201702280. View the Front Cover here: 10.1002/cssc.201800464.
Abstract
Invited for this month's cover is the group of Prof. Tong‐Bu Lu at Sun Yat‐Sen University/Tianjin University of Technology. The Cover picture depicts a beautiful lady, an imaginary figure of ...a forest fairy, praying with an Earth‐like crystal ball that is filled with cobalt complexes, aiming to realize the transformation of atmospheric CO
2
to CO The Full Paper itself is available at
10.1002/cssc.201702280
.
The reduction of carbon dioxide (CO
) has been considered as an approach to mitigate global warming and to provide renewable carbon-based fuels. Rational design of efficient, selective, and ...inexpensive catalysts with low overpotentials is urgently desired. In this study, four cobalt(II) tripodal complexes are tested as catalysts for CO
reduction to CO in a MeCN/H
O (4:1 v/v) solution. The replacement of pyridyl groups in the ligands with less basic quinolinyl groups greatly reduces the required overpotential for CO
-to-CO conversion down to 200-380 mV. Benefitting from the low overpotentials, a photocatalyst system for CO
-to-CO conversion is successfully constructed, with an maximum turnover number (TON) of 10 650±750, a turnover frequency (TOF) of 1150±80 h
, and almost 100 % selectivity to CO. These outstanding catalytic performances are further elucidated by DFT calculations.
Single‐crystal X‐ray diffraction analysis of polybis(μ2‐5‐carboxy‐2‐propyl‐1H‐imidazole‐4‐carboxylato‐κ3N3,O4:O5)copper(II), Cu(C8H9N2O4)2)n, indicates that one carboxylic acid group of the ...2‐propyl‐1H‐imidazole‐4,5‐dicarboxylic acid (H3PDI) ligand is deprotonated. The resulting H2PDI− anion, acting as a bridge, connects the CuII cations to form a two‐dimensional (4,4)‐connected layer. Adjacent layers are further linked through interlayer hydrogen‐bond interactions, resulting in a three‐dimensional supramolecular structure.
Dual‐atom catalysts (DACs) have emerged as efficient electrocatalysts for CO2 reduction owing to the synergistic effect between the binary metal sites. However, rationally modulating the electronic ...structure of DACs to optimize the catalytic performance remains a great challenge. Herein, we report the electronic structure modulation of three Ni2 DACs (namely, Ni2−N7, Ni2−N5C2 and Ni2−N3C4) by the regulation of the coordination environments around the dual‐atom Ni2 centres. As a result, Ni2−N3C4 exhibits significantly improved electrocatalytic activity for CO2 reduction, not only better than the corresponding single‐atom Ni catalyst (Ni−N2C2), but also higher than Ni2−N7 and Ni2−N5C2 DACs. Density functional theory (DFT) calculations revealed that the high electrocatalytic activity of Ni2−N3C4 for CO2 reduction could be attributed to the electronic structure modulation to the Ni centre and the resulted proper binding energies to COOH* and CO* intermediates.
Three Ni2 dual‐atom catalysts (DACs) with electronic structures tailored by the regulation of the coordination environment of Ni atoms, have been prepared for electrocatalytic CO2 reduction. The optimal Ni2−N3C4 exhibits the highest performance for the reduction of CO2 to CO, highlighting the significance of the electronic structure for electrocatalytic CO2 reduction in DACs.
It is common that different crystal facets in metal and metal oxide nanocrystals display different catalytic performances, whereas such phenomena have been rarely documented in metal–organic ...frameworks (MOFs). Herein, we demonstrate for the first time that a nickel metal–organic layer (MOL) exposing rich (100) crystal facets (Ni‐MOL‐100) shows a much higher photocatalytic CO2‐to‐CO activity than the one exposing rich (010) crystal facets (Ni‐MOL‐010) and its bulky counterpart (bulky Ni‐MOF), with a catalytic activity up to 2.5 and 4.6 times more active than Ni‐MOL‐010 and bulky Ni‐MOF, respectively. Theoretical studies reveal that the two coordinatively unsaturated NiII ions with a close distance of 3.50 Å on the surface of Ni‐MOL‐100 enables synergistic catalysis, leading to more favorable energetics in CO2 reduction than that of Ni‐MOL‐010.
Crystal‐facet‐dependent catalytic performance for CO2 reduction has been observed in Ni‐based 2D MOLs. Ni‐MOL‐100 displays much higher catalytic activity than Ni‐MOL‐010, benefiting from the synergistic catalysis between two adjacent Ni sites in Ni‐MOL‐100.
A novel 3D layer-pillared metal-organic framework of Cd3(IDC)(BDC)1.5(H2O)n (1), (H3IDC=imidazole-4,5-dicarboxylic acid, H2BDC=1,4-benzenedicarboxylic acid) was obtained by hydrothermal reaction, ...which contains rare planar hexnuclear Cd(II) cluster structural units and represents an unprecedented trinodal (4,5,14)-connected topology network. Furthermore, the thermal stability and luminescent property of 1 have also been examined.
An unprecedented 3D (4,5,14)-connected layer-pillared metal-organic framework of Cd3(IDC)(BDC)1.5(H2O)n (1) (H3IDC=imidazole-4,5-dicarboxylic acid, H2BDC=1,4-benzenedicarboxylic acid) containing rare hexnuclear Cd(II) clusters has been hydrothermally synthesized. Photoluminescent measurement illustrates 1 emits strong luminescence at 465nm. Display omitted
► A novel 3D layer-pillared MOF based on mixed rigid ligands has been synthesized. ► It contains rare planar hexnuclear Cd(II) clusters as SBU. ► The framework displays a rare trinodal (4,5,14)-connected topology. ► Its thermal stability and luminescent property have also been investigated.
► Two Ni(II) complexes of H3PIDC and Bipy were synthesized by solvent tuned method. ► Bipy ligand acts as template and bridge in 1 and 2, respectively. ► The change of Bipy ligand function due to the ...change of solvent.
Two nickel(II) complexes, (H2Bipy)0.5Ni(H2PIDC)3·(Bipy)·5H2O (1) and Ni(H2PIDC)2(Bipy)n (2) (H3PIDC=2-propyl-4,5-dicarboxylate-imidazole, Bipy=4,4′-bipyridine), have been solvothermally synthesized and structurally characterized by infrared spectra (IR), elemental analysis, thermogravimetic analysis (TG), and single-crystal/powder X-ray diffraction. The single-crystal X-ray diffraction analysis indicates that 1 is a mononuclear coordination compound, in which the Ni(H2PIDC)3− coordination units are connected together through indirect hydrogen interactions to form a 3D supramolecular structure with 1D supramolecular channels. The Bipy and H2Bipy2+, as templates, fill in the channels. 2 is a 1D chain-shaped coordination polymer, in which the Bipy molecules serve as bridging ligand linking the Ni(H2PIDC)2 units together to form a 1D chain. Through the interactions of intermolecular hydrogen bonds, these 1D chains are further stacked together to form a 3D overpass-like supramolecular network.
