Molecular Engineering of Methylated Sulfone-Based Covalent Organic Frameworks for Back-Reaction Inhibited Photocatalytic Overall Water Splitting.

Solar-to-hydrogen (H) and oxygen (O) conversion via photocatalytic overall water splitting (OWS) holds great promise for a sustainable fuel economy, but has been challenged by the backward O reduction reaction (ORR) with favored proton-coupled electron transfer (PCET) dynamics. Here, we report that molecular engineering by methylation inhibits the backward ORR of molecular photocatalysts and enables efficient OWS process. As demonstrated by a benchmark sulfone-based covalent organic framework (COF) photocatalyst, the precise methylation of its O adsorption sites effectively blocks electron transfer and increases the barrier for hydrogen intermediate desorption that cooperatively obstructs the PCET process of ORR.

Temporally Decoupled Ammonia Splitting by a Zn-NH Battery with an Ammonia Oxidation/Hydrogen Evolution Bifunctional Electrocatalyst as a Cathode.

Ammonia splitting to hydrogen is a decisive route for hydrogen economy but is seriously limited by the complex device and low efficiency. Here, we design and propose a new rechargeable Zn-NH battery based on temporally decoupled ammonia splitting to achieve efficient NH-to-H conversion. In this system, ammonia is oxidized into nitrogen during cathodic charging (2NH + 6OH → N + 6HO + 6e) with external electrical energy conversion and storage, while during cathodic discharging, water is reduced to hydrogen (2HO + 2e → H + 2OH) with electrical energy generation.

Coupling Electron Transfer and Redox Site in Boranil Covalent Organic Framework Toward Boosting Photocatalytic Water Oxidation.

The efficient polymeric semiconducting photocatalyst for solar-driven sluggish kinetics with multielectron transfer oxygen evolution has spurred scientific interest. However, existing photocatalysts limited by π-conjugations, visible-light harvest, and charge transfer often compromise the O production rate. Herein, we introduced an alternative strategy involving a boranil functionalized-based fully π-conjugated ordered donor and acceptor (D-A) covalent organic frameworks (Ni-TAPP-COF-BF ) photocatalyst.

Overcoming the Trade-Off between C H Sorption and Separation Performance by Regulating Metal-Alkyne Chemical Interaction in Metal-Organic Frameworks.

Designing porous materials for C H purification and safe storage is essential research for industrial utilization. We emphatically regulate the metal-alkyne interaction of Pd and Pt on C H sorption and C H /CO separation in two isostructural NbO metal-organic frameworks (MOFs), Pd/Cu-PDA and Pt/Cu-PDA. The experimental investigations and systematic theoretical calculations reveal that Pd in Pd/Cu-PDA undergoes spontaneous chemical reaction with C H , leading to irreversible structural collapse and loss of C H /CO sorption and separation.

The Combination of Charge and Energy Transfer Processes in MOFs for Efficient Photocatalytic Oxidative Coupling of Amines.

Combining electron and energy transfer processes is very significant for efficient photocatalytic oxidation of organic molecules. The first synthesized MOF, Co(L)(2,6-NDC)·guest (, L = bis(-pyridyl) tetrachloroperylene peryleneimide, 2,6-NDC = 2,6-naphthalenedicarboxylic acid, FJI = Fujian Institute), shows a 2-fold interpenetrated net, in which the 2,6-NDC ligand connects typical Co(COO) paddle wheel clusters to form square lattices pillared by new PDI-type ligand L. as a heterogeneous and recyclable photocatalyst is applied for photo-oxidation of benzylamine and its derivatives with an excellent yield of 100%, which is much higher than that (59%) of the equivalent L ligand as a homogeneous photocatalyst under the same reaction conditions.

Optimizing H, D, and CH Sorption Properties by Tuning the Pore Apertures in Metal-Organic Frameworks.

By adjustment of the arm lengths of two triphenylamine-based ligands, two nearly isostructural metal-organic frameworks (MOFs), namely, the reported nanoporous FIR-29 (FIR = Fujian Institute of Research) and the new microporous FJI-Y9 (FJI = Fujian Institute), are obtained, and all exhibit honeycomb lattices of hexagonal channels with Ca-COO chains connected by tris[(4-carboxyl)phenylduryl]amine (HTCPA) ligands and 4,4',4''-nitrilotribenzoic acid (HNTB) ligands, respectively. Although the Brunauer-Emmett-Teller (BET) surface area (1117 m g) and pore size (8.5 Å) of FJI-Y9 are much lower than those (BET surface area of 2061 m g and pore size of 16 Å) of the reported FIR-29 because of the shorter arm lengths of HNTB, the activated FJI-Y9-ht shows high H (202.

Direct Solar-to-Electrochemical Energy Storage in a Functionalized Covalent Organic Framework.

A covalent organic framework integrating naphthalenediimide and triphenylamine units (NT-COF) is presented. Two-dimensional porous nanosheets are packed with a high specific surface area of 1276 m  g . Photo/electrochemical measurements reveal the ultrahigh efficient intramolecular charge transfer from the TPA to the NDI and the highly reversible electrochemical reaction in NT-COF.

Design and synthesis of multifunctional metal-organic zeolites.

Metal-organic zeolites (MOZs) are an important branch of metal-organic frameworks (MOFs) and combine the advantages of zeolites and MOFs, such as high surface area and porosity as well as the exceptional stability of zeolites, which would have a significant impact on catalysis chemistry, inorganic chemistry, coordination chemistry, materials science and other areas. In this review, we focus on the recent advances in MOZs with a brief outline of the most prominent examples. In particular, we highlight the basic principles of the design and synthesis approaches toward the construction of MOZs.

Rational design of a flu-type heterometallic cluster-based Zr-MOF.

Following the HSAB principle, the cooperative assembly of tetrahedral [CuI(Ina)] metalloligands and 8-connecting [Zr(μ-OH)(OH)] building units leads to the first heterometallic cluster-based Zr-MOF (1). The results provide a successful strategy for rational design of heterometallic cluster-based Zr-MOFs.

Gas Sorption, Second-Order Nonlinear Optics, and Luminescence Properties of a Multifunctional srs-Type Metal-Organic Framework Built by Tris(4-carboxylphenylduryl)amine.

A chiral 8-fold interpenetrating srs-type metal-organic framework FIR-28 (FIR denotes Fujian Institute of Research) exhibits a surface area of 1029 m(2)/g and high C3H8/CH4 separation capacity in excess of 154 and displays strong powder second-harmonic-generation efficiency, with more than half over potassium dihydrogen phosphate powder. Moreover, the luminescence properties of FIR-28 are dependent on the solvent guests.

Integration of rigid and flexible organic parts for the construction of a homochiral metal-organic framework with high porosity.

Presented is a pair of homochiral metal-organic frameworks built from mixed ligands integrating rigid and flexible organic parts, and each compound shows high porosity and can be used for enantioselective separation of racemic 1-phenethylalcohol and methyl lactate.

Multifunctional anionic MOF material for dye enrichment and selective sorption of C2 hydrocarbons over methane via Ag(+)-exchange.

The anionic Zn-2,5-thiophenedicarboxylate framework material (1) built from the connection of Johnson cages can perform Ag(+)-exchange to upgrade the uptakes of C2 hydrocarbons (C2s) and separation properties of C2s over methane (C1). Moreover, its activated phase (1a) can enrich organic dyes from ethanol and make a significant red-shift in photoluminescent spectra of Rhodamine B (Rh B) via varying the aggregation states of dye molecules.

Homochiral metal-organic frameworks with enantiopure proline units for the catalytic synthesis of β-lactams.

Two enantiopure organic ligands integrating flexible proline units and rigid isophthalate units have been rationally designed and employed for the construction of four homochiral porous metal-organic frameworks (MOFs), respectively. One pair of these MOFs is used as heterogeneous catalysts to construct β-lactam derivatives by oxidative coupling reactions.

Cooperative ion-exchange and self-redox process to load catalytic metal nanoparticles into a MOF with Johnson-type cages.

Through a cooperative ion-exchange and self-redox process, a new MOF material with nanosized Johnson-type cages has successfully produced Pd- or Ag-NPs in its pores without any external reducing agents, leading to the formation of M-NP-embedded catalysts for the hydrogenation of styrene.

Nanoporous cobalt(II) MOF exhibiting four magnetic ground states and changes in gas sorption upon post-synthetic modification.

We present the syntheses, structural characterization, gas sorption, I2 uptake, and magnetic properties of a double-walled porous metal-organic framework, [Co(II)3(lac)2(pybz)2]·3DMF (1·3DMF, purple, where pybz = 4-pyridyl benzoate, lac = d- and l-lactate) and of its post-synthetic modified (PSM) congeners, [Co(II)3(lac)2(pybz)2]·xGuest (xGuest = 6MeOH, purple; 4.5EtOH, purple; 3PrOH, purple; 2C6H6, purple; 2.7I2, black), [Co(II)3(lac)2(pybz)2] (1, purple), [Co(II)3(pybz)2(lac)2(H2O)2]·7H2O (1a·7H2O, green), and [Co(III)Co(II)2(pybz)2(lac)2(H2O)2]I·2H2O·1.

Structural diversity and photoluminescent properties of zinc benzotriazole-5-carboxylate coordination polymers.

A series of zinc(II) compounds, [Zn2(btca)2(im)2]·(DMA) (1; H2btca = benzotriazole-5-carboxylate acid, im = imidazole, and DMA = N,N-dimethylacetamide), [Zn(btca)(im)]·(DMF) (2; DMF = N,N-dimethylformamide), [Zn2(btca)2(tmdpy)]·2(DMF)·5(H2O) [3; tmdpy = 1,3-di(4-pyridyl)propane], and [H2N(CH3)2]2[Zn3(btca)4]·(DMF) (4), have been successfully synthesized via rational control of experimental conditions. Single-crystal X-ray diffraction analyses indicate that compounds 1 and 2 are isomers, and both of them exhibit two-dimensional structures with the same uninodal 3-connected fes topology. Additionally, the three-dimensional (3D) structure of 3 was obtained by using tmdpy instead of an im ligand under synthesis conditions similar to those of compound 2.

Tuning a layer to a pillared-layer metal-organic framework for adsorption and separation of light hydrocarbons.

Rational assembly from a layer structure to a pillared-layer metal-organic framework affords an ideal microporous material with large Langmuir surface area for highly selective separation of hydrocarbons.

Gas sorption, second-order nonlinear optics, and luminescence properties of a series of lanthanide-organic frameworks based on nanosized tris((4-carboxyl)phenylduryl)amine ligand.

By controlling the pH value of the reaction system, two sets of lanthanide (Ln)-tris((4-carboxyl)phenylduryl)amine (Ln = Ce, Pr, Nd, Sm) frameworks have been generated. Four isostructural noninterpenetrating frameworks (FIR-8 to FIR-11) are constructed from rod-shaped secondary building units and four other isostructural frameworks (FIR-12 to FIR-15) based on single Ln nodes are described as 8-fold interpenetrating dia-type nets. Gas sorption measurements for FIR-8 give a Langmuir surface area of 633.

A porous 4-fold-interpenetrated chiral framework exhibiting vapochromism, single-crystal-to-single-crystal solvent exchange, gas sorption, and a poisoning effect.

The synthesis and characterization of a 4-fold-interpenetrated pseudodiamond metal-organic framework (MOF), Co(II)(pybz)2·2DMF [pybz = 4-(4-pyridyl)benzoate], are reported. N,N-Dimethylformamide (DMF) of the channels can be removed to give the porous framework, and it can also be exchanged for methanol, ethanol, benzene, and cyclohexane. It is a rare example of a stable MOF based on a single octahedral building unit.

Comparative study of activation methods on tuning gas sorption properties of a metal-organic framework with nanosized ligands.

Presented here is a new porous metal-organic framework based on a nanosized tris((4-carboxyl)phenylduryl)amine ligand, which features a 2-fold interpenetrating hms network and shows distinct gas adsorption behaviors dependent on different activation methods.

Tuning MOF stability and porosity via adding rigid pillars.

High stability and permanent porosity are the premise of general applicability for metal-organic framework materials (MOFs). By varying degrees of success on increasing the connectivity of the linear pillar 4,4'-bipyridine (bpy), two isostructural flexible frameworks [M(2)(obb)(2)(DMF)(2)]·2DMF (1, M = Zn or Cu; H(2)obb = 4,4'-oxybis(benzoic acid), DMF = N,N-dimethylformamide) with no gas sorption are structurally modified into two rigid frameworks [Zn(2)(obb)(2)(bpy)]·DMF (2) and [Cu(2)(obb)(2)(bpy)(0.5)(DMF)]·2DMF (3) with notable gas sorption and separation properties.

Temperature-/pressure-dependent selective separation of CO(2) or benzene in a chiral metal-organic framework material.

Presented here is a chiral microporous metal-organic framework material with a three-fold interpenetrating diamond-type structural topology and interesting properties for selective separation. The material has a high storage capacity for CO(2) gas (4.23 mmol g(-1) at 273 K and 1 bar) and shows fantastic temperature-dependent selectivity for CO(2) over N(2).

Open diamondoid amino-functionalized MOFs for CO2 capture.

Solvent-induced chiral single-crystal to achiral single-crystal structural transformation is presented by two isomeric amino-functionalized metal-organic frameworks with 2-fold interpenetrating diamond topology, and the achiral form has high CO(2) uptake capacity.

Charge matching on designing neutral cadmium-lanthanide-organic open frameworks for luminescence sensing.

Through careful consideration of charge matching, a simple replacement of metal ion from Cd(2+) to Ln(3+) in a building unit successfully transforms an anionic microporous framework into a series of isostructural porous neutral heterometallic frameworks [Cd(3)Ln(2)(btc)(4)(H(2)O)(6)(dmf)(4)]·x(solvent) (1; Ln=Tb, Eu, Nd, Gd, Sm, dmf=N,N'-dimethylformamide) by employing five different lanthanide ions. 1-Tb and 1-Eu exhibit interesting photoluminescent properties, and remarkably, 1-Tb can act as a luminescent sensor to identify organic solvents and metal ions.