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Thermal stability and thermodynamic properties of aluminum(III)-1,3,5-benzenetricarboxylate (Al-BTC) metal-organic frameworks (MOFs), including MIL-96, MIL-100, and MIL-110, have been investigated through a suite of calorimetric and X-ray techniques.

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Ethylene (C

One-dimensional (1D) organic-inorganic hybrid lead halides with unique core-shell quantum wire structures and splendid photoluminescence properties have been considered one of the most promising high-efficiency broadband emitters. However, studies on the broadband emissions in 1D purely face-shared lead iodide hybrids are still rare so far. Herein, we report on a new 1D lead iodide hybrid, (2cepyH)PbI3 (2cepy = 1-(2-chloroethyl)pyrrolidine), characterized with face-sharing PbI6 octahedral chains. Upon UV photoexcitation, this material shows broadband yellow emissions originating from the self-trapped excitons associated with distorted Pb-I lattices on account of the strong exciton-phonon coupling, as proved by variable-temperature emission spectra. Moreover, experimental and calculated results reveal that (2cepyH)PbI3 is an indirect bandgap semiconductor, the band structures of which are governed by inorganic parts. Our work represents the first broadband emitter based on a 1D face-shared lead iodide hybrid and opens a new way to obtain the novel broadband emission materials.

Transition metals with 3d unoccupied orbitals have superior catalytic activity, but inherent high spin suppresses their adsorption capability, leading to sluggish polysulfide conversion kinetics for Li-S batteries. Herein, we provide Fe-O-Si bridge bonds to manipulate

Reactions of cerium and nickel in excess molten gallium were monitored by neutron diffraction during heating and cooling. The formation of binary intermediates CeGa

Titanium-oxide or polyoxotitanate clusters are a new type of inorganic host materials that can encapsulate inorganic molecules or ions. We report herein a (NH4)4(enH2)[Ti18O27(PhCOO)24(en)9] molecular cage (Ti18) that encapsulates an entire organic ethylenediamine (en) ion. A thorough investigation has revealed the extraordinary versatility of en. Besides being a guest cation, it also functions as chelating and bridging ligand. It balances the charge of the negative Ti18 cage and facilitates the deprotonation of benzoic acid at the early stage of the reaction as well. DFT calculation and a derivative of Ti18 with open sites at its equatorial position shed further light on the formation mechanism. Ti18 strongly absorbs visible light as a result of en coordination, and it exhibits superior photocatalytic activity compared to anatase TiO2.

Polycrystalline LiMo

Exploiting the well-arranged and tunable frameworks of crystalline materials, we herein report coordination polymers (CPs) with modulated hierarchical structures as triboelectric materials to construct and extend the application scope of triboelectric nanogenerators (TENGs). Different lengths and shapes of bridging ligands [4,4'-bpa = 1,2-bis(4-pyridyl)ethane, 4,4'-bpe = 1,2-bis(4-pyridyl)ethene, and 4,4'-bpp = 1,3-di(2-pyridyl)propane for

Bi

We report room-temperature (RT) magnetoresistance (MR) in a novel Fe-based perovskite, SrV

The preparation, complex magnetic properties and room-temperature magnetocaloric effect in Nd(Cu

The [Nb@As

Motivated by the predicted unusual short Ni—Ni bond length that is comparable to the intermetallic distance anticipated for the triple bond, the nature of Ni—Ni bonding interaction in the triply ca...

A series of highly active MnO2@REOx (RE = Gd, Sm, Ce, and La) catalysts were successfully synthesized via in situ growth on the surface of MnO2, wherein the rare earth oxides were planted on the defect sites left by hydrogen peroxide etching of the surface of MnO2. Their physicochemical performance was investigated by scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD), N2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction with hydrogen (H2-TPR), and temperature-programmed desorption of oxygen (O2-TPD). The catalytic properties are compared through the catalytic oxidation of chlorobenzene. Among all catalysts, MnO2@GdOx showed better mobility of surface lattice oxygen and higher molar ratios of Mn4+/Mn3+ (1.10) and Oads/Olatt (0.45), which promoted the superior low-temperature catalytic activity for chlorobenzene oxidation. The long-term chlorobenzene oxidation test (18 h) at different temperatures and the experiments with a mixture of VOCs showed that the as-prepared catalyst not only possessed a high stability but also was suitable for the efficient and simultaneous removal of multicomponent VOCs (toluene, benzene, acetone, and chlorobenzene). This work also provided an idea for the further development of high-efficiency catalysts for the purification of VOCs from complex atmosphere environment.

Developing an effective strategy to synthesize perfect titanosilicate TS-1 zeolite crystals with desirable morphologies, enriched isolated framework Ti species, and thus enhanced catalytic oxidation properties is a pervasive challenge in zeolite crystal engineering. We here used an amino acid l-carnitine as a crystal growth modifier and ethanol as a cosolvent to regulate the morphologies and the Ti coordination states of TS-1 zeolites. During the hydrothermal crystallization process, the introduced l-carnitine can not only tailor the anisotropic growth rates of zeolite crystals but also induce the formation of uniformly distributed framework Ti species through building a suitable chemical interaction with the Ti precursor species. Condition optimizations could afford the generation of perfect hexagonal plate TS-1 crystals and elongated platelet TS-1 crystals enriched in tetrahedral framework Ti sites (TiO

Bi and Pb ions with charge degree of freedom depending on 6s2 and 6s0 electronic configurations were combined with the Mn ion in a perovskite oxide. Comprehensive theoretical and experimental inves...

One-dimensional (1D) organic-inorganic hybrid lead halides with unique core-shell quantum wire structures and splendid photoluminescence properties have been considered one of the most promising high-efficiency broadband emitters. However, studies on the broadband emissions in 1D purely face-shared lead iodide hybrids are still rare so far. Herein, we report on a new 1D lead iodide hybrid, (2cepyH)PbI

Metal organic frameworks (MOFs) of the type NBu4M(DHBQ)1.5 (M = Ni2+, Fe2+, and Co2+; DHBQ = 2,5-dihydroxy-1,4-benzoquinone) were prepared with improved yield up to 100% via a simple benchtop aqueous addition reaction. For the first time, the crystalline phase of this formula polymer was synthesized without in situ generation of the DHBQ ligand from 2, 5-diamino-1,4-benzoquinone (DABQ). Powder X-ray diffraction and elemental analysis confirm the crystalline phase and composition of products. Infrared and electron dispersive spectroscopy further confirm that the materials are homologous to the reported single crystalline polymers. The present MOF synthesis can be extended to halide-substituted ligands, i.e., 3,6-dichloro-2,5-dihydroxy-1,4-benzoquinone (chloranilic acid, CAN) and 3,6-difluoro-2,5-dihydroxy-1,4-benzoquinone (fluoranilic acid, FAN).

Aluminum-based metal-organic frameworks (Al-MOFs) have shown promise as commercially valuable materials due to the variety of applications, excellent thermal, hydrothermal, and chemical stabilities, and the abundance of aluminum. In this work, for the first time, we report the solvent-free synthesis of the aluminum trimesate (Al-BTC) MOFs (MIL-100(Al), MIL-96(Al), and MIL-110(Al)) with phase selectivity and high yield. These MOFs were traditionally prepared with HF, HNO3, and bulk solvents, but these methods struggled to produce pure-phase isolations. The solvent-free strategy provides valuable insight into the future industrial scale-up production of the Al-MOFs and promotes the potential commercialization of such materials.

Two cadmium coordination polymers, WSU-30 and WSU-31, were synthesized through solvothermal methods by using the low-symmetry TPE-based linker m-H4ETTC. The m-H4ETTC linker and both coordination po...

A series of highly active MnO

Bi and Pb ions with charge degree of freedom depending on 6

A photoactive triazolobenzothiadiazole (TBTD)-conjugated terphenyldicarboxylate (TPDC) linker was introduced into a porous and robust UiO-68 isoreticular zirconium metal-organic framework (denoted as UiO-68-TBTD) by the de novo synthetic approach of mixed TPDC struts. Under blue-light-emitting-diode irradiation, UiO-68-TBTD can serve as a heterogeneous photocatalyst for the highly efficient and selective oxidation of a sulfur mustard simulant (2-chloroethyl ethyl sulfide) to the corresponding much less toxic sulfoxide product, with a half-life of only 3 min in the open air atmosphere.

A variety of Eu3+-activated BaZrGe3O9 phosphors was synthesized via solid-state reaction. The phase formation of BaZrGe3O9:Eu3+ samples was verified by powder X-ray diffraction analysis, while Rietveld refinement method was used to confirm the crystal structure. The electronic structure and characteristic photoluminescence as well as cathodoluminescence properties were researched in detail. The samples show strong absorption at 394 nm, which matches well with the commercial near-ultraviolet chips. Under 394 nm excitation, the phosphors exhibit the characteristic emissions of Eu3+ ions consistent with the 5D0–7FJ transitions. Then we investigated the thermal stability detailedly. The temperature-dependent photoluminescence emission spectra suggest that the obtained phosphors have favorable thermal stability. A white light-emitting diode (WLED) lamp with low correlated color temperature and good color render index was fabricated with blue-emitting BaMgAl10O17:Eu2+, green-emitting Sr2SiO4:Eu2+ (commercial), ...

Heavy-metal ions and nitroaromatic substances are highly toxic and harmful to human health and the ecological environment. It is an urgent issue to selectively detect and capture these toxic substances. By introducing the triazole ligand to the π-conjugated aromatic carboxylate system and borrowing the organic template open framework idea, a stable fluorescent framework [Me2NH2]4[Zn6(qptc)3(trz)4]·6H2O (1) (H4qptc = terphenyl-2,5,2′5′-tetracarboxylic acid, trz = 1,2,4-triazole) has been successfully synthesized, which features Zn4(trz)2 chain-based 3D anionic structure with channels filled by [Me2NH2]+ cations. It is worth noting that the material exhibits selective adsorption and recyclable detection of heavy-metal Cr3+ ion in aqueous solutions, which may be the synergy from the metal charge, bond ability of metal ions to carboxylate oxygen atom, and soft–hard acid–base properties. Furthermore, it can selectively sense of 2,4,6-trinitrophenol with a large quenching coefficient Ksv of 2.08 × 106 M–1.

Zinc oxide, ZnO, an important technologically relevant binary compound, was investigated by reciprocating compress the sample in a diamond anvil cell using in situ high-pressure synchrotron X-ray diffraction at room temperature. The starting sample (∼200 nm) was compressed to 20 GPa and then decompressed to ambient condition. The quenched sample, with average grain size ∼10 nm, was recompressed to 20 GPa and then released to ambient condition. The structural stability and compressibility of the initial bulk ZnO and quenched nano ZnO were compared. Results reveal that the grain size and the fractional cell distortion have little effect on the structural stability of ZnO. The bulk modulus of the B4 (hexagonal wurtzites structure) and B1 (cubic rock salt structure) phases for bulk ZnO under hydrostatic compression were estimated as 164(3) and 201(2) GPa, respectively. Importantly, the effect of pressure in atomic positions, bond distances, and bond angles was obtained. On the basis of this information, the B4-to-B1 phase transformation was demonstrated to follow the hexagonal path rather than the tetragonal path. For the first time, the detail of the intermediate hexagonal ZnO, revealing the B4-to-B1 transition mechanism, was detected by experimental method. These findings enrich our knowledge on the diversity of the size influences on the high-pressure behaviors of materials and offer new insights into the mechanism of the B4-to-B1 phase transition that is commonly observed in many other wurzite semiconductor compounds.

A chiral C3-symmetric cubane cluster, [Cu4I4(TMP)4], with enough long Cu-Cu distances to eliminate the presence of Cu-Cu interaction has been synthesized and characterized, which shows simultaneous luminescent thermochromism, solvatochromism, vapochromism, and mechanochromism and is a multiply stimuli-responsive chromic luminescent material. This complex could partly transform into a yellow-emissive bicapped cubane cluster, [Cu6I6(TMP)4(MeCN)2], in acetonitrile (MeCN) vapor and solution, which provides some insight into vapochromism and solvatiochromism. This work challenges and makes us reconsider the conventional viewpoint that Cu-Cu interaction is involved in thermochromism and mechanochromism of copper complexes.

A variety of Eu

Heavy-metal ions and nitroaromatic substances are highly toxic and harmful to human health and the ecological environment. It is an urgent issue to selectively detect and capture these toxic substances. By introducing the triazole ligand to the π-conjugated aromatic carboxylate system and borrowing the organic template open framework idea, a stable fluorescent framework [Me

A porous luminescent zinc(II) metal–organic framework (MOF) with a NbO net [Zn2(tptc)(apy)2–x(H2O)x]·H2O (1) (where x ≈ 1, apy = aminopyridine, H4tptc = terphenyl-3,3″,5,5″-tetracarboxylic acid), constructed using paddlewheel [Zn2(COO)4] clusters and π-electron-rich terphenyl-tetracarboxylic acid, has been solvothermally synthesized and characterized. Interestingly, the material displays efficient, reversible adsorption of radioactive I2 in vapor and in solution (up to 216 wt %). The strong affinity for I2 is mainly due to it having large porosity, a conjugated π-electron aromatic system, halogen bonds, and electron-donating aminos. Furthermore, luminescent study indicated that 1 exhibits high sensitivity to electron-deficient nitrobenzene explosives via fluorescence quenching.

A zirconium(IV)-based UiO-topological metal–organic framework (UiO-68Se) containing benzoselenadiazole was synthesized by an approach of the mixed dicarboxylate struts, which show highly efficient and recycalable photocatalytic activity for aerobic cross-dehydrogenative coupling reactions between tertiary amines and various carbon nucleophiles under visible-light irradiation.

Two monoxides of typical smaller chlorofullerenes, (#271)C50Cl10O and (#913)C56Cl10O, featured with double-fused-pentagons, were synthesized to demonstrate further regioselective functionalization of non-IPR (IPR = isolated pentagon rule) chlorofullerenes. Both non-IPR chlorofullerene oxides exhibit an epoxy structure at the ortho-site of fused pentagons. In terms of the geometrical analysis and theoretical calculations, the principles for regioselective epoxy oxidation of non-IPR chlorofullerenes are revealed to follow both "fused-pentagon ortho-site" and "olefinic bond" rules, which are valuable for prediction of oxidation of non-IPR chlorofullerenes.

In this paper, a water-ethanol-oleic acid system was developed to prepare LiREF(4) nanocrystals with a controlled size and shape. The influence of LiOH concentration and temperature on the phase and shape evolution of the LiREF(4) nanocrystals was systematically investigated and discussed. It was found that the LiOH concentration was the key factor responsible for the shape evolution and phase control for LiREF(4) nanocrystals at selected temperatures. The LiYF(4)-LiLuF(4) core-shell nanostructure was synthesized and characterized.

Two new bent oxadiazole bridging benzoacetylene ligands 2,5-bis(4-ethynylphenyl)-1,3,4-oxadiazole (L9) and 2,5-bis(3-ethynylphenyl)-1,3,4-oxadiazole (L10) were synthesized. The coordination chemistry of them with various inorganic Ag(I) salts has been investigated. Seven new coordination polymers were prepared by solution reactions and fully characterized by infrared spectroscopy, elemental analysis, and single-crystal X-ray diffraction. [Ag2(L9)](SO3CF3)2 (1) (triclinic, P; a =10.292(4), b = 10.794(4), c = 11.399(5) A; alpha = 98.894(5), beta = 102.360(6), gamma = 90.319(5) degrees ; Z = 2), [Ag(L9)]SbF6 (2) (orthorhombic, Cmca; a = 19.059(9), b = 12.922(6), c = 15.609(7) A; Z = 8), [Ag(L9)]BF4 (3) (orthorhombic, Cmca; a = 19.128(3), b = 12.6042(18), c = 28.003(4) A; Z = 16), [Ag(L9)]ClO4 (4) (monoclinic, P2(1)/c; a = 8.5153(16), b = 19.722(4), c = 10.320(2) A; beta = 105.307(3) degrees ; Z = 4), [Ag(L10)]SO3CF3 (5) (triclinic, P; a = 9.0605(13), b = 10.4956(15), c = 10.8085(16) A; alpha = 101.666(2), beta = 109.269(2), gamma = 100.944(2) degrees ; Z = 2), [Ag(L10)(H2O)(0.5)]BF4.0.5H2O (6) (monoclinic, C2/m; a = 32.180(6), b = 17.027(3), c = 8.1453(15) A; beta = 102.541(3) degrees ; Z = 8), and {[Ag2(L10)2(H2O)](ClO4)2}.o-xylene (7) (monoclinic, P2(1)/c; a = 8.1460(10), b = 17.326(2), c = 30.345(4) A; beta = 97.71 degrees ; Z = 4) were obtained by the combination of L9 and L10 with various Ag(I) salts in a benzene/methylene chloride mixed solvent system. In addition, the luminescent and electrical conductive properties of these new compounds were investigated.

Two Cu(II) coordination complexes {[Cu(ces)(H(2)O)(2)](H(2)O)(0.5)}(n) (1) and [Cu(15)(dhs)(6)(OH)(6)(H(2)O)(10)](H(2)O)(20) (2) have been synthesized from cis-epoxysuccinic acid (cis-H(2)ces) and Cu(II) perchlorate under different pH conditions (ces = cis-epoxysuccinate and dhs = 2,3-dihydroxysuccinate), and fully characterized by IR spectra, elemental analyses, as well as single crystal and powder X-ray diffraction techniques. Notably, when the reaction was performed at pH above about 7.4, a one-dimensional (1-D) helical chain complex 1 is formed, whereas a neutral isolated Cu(15) nanocluster 2 is generated when the pH value is decreased to the range of about 6.6-7.3, being concomitant with in situ S(N)2 ring-cleavage reaction of cis-H(2)ces to form (2S,3S)- and (2R,3R)-H(4)dhs. Further, extended supramolecular architectures are constructed via secondary interactions in both structures. The magnetic properties of 1 and 2 have also been studied in detail, showing that 1 is an antiferromagnetic helical chain of S = 1/2 spins and 2 possesses an S = 3/2 spin ground state.