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One homo-trinuclear 3d and five novel windmill-type hetero-pentanuclear 3d-4f complexes [Zn3(L)(OAc)2(H2O)]·CH2Cl2 (1), [Zn4(L)2Sm(NO3)2(EtOH)2]NO3·H2O·2CHCl3 (2), [Zn4(L)2Eu(NO3)2(EtOH)2]NO3·C2H5OH·2CHCl3 (3), [Zn4(L)2Gd(NO3)2(EtOH)2]NO3·C2H5OH·2CHCl3 (4), [Zn4(L)2Tb(NO3)2(EtOH)2]NO3·C2H5OH (5) and [Zn4(L)2Dy(NO3)2(EtOH)2]NO3·C2H5OH·2CHCl3 (6) were synthesized by the reactions of a new bis(Salamo)-based tetraoxime ligand (H4L) with Zn(OAc)2·2H2O and Ln(NO3)3·6H2O (Ln = Sm, Eu, Gd, Tb and Dy), respectively. The structures of complexes 1–6 were characterized via elemental analyses, FT-IR spectroscopy, UV-Vis spectroscopy and single crystal X-ray crystallography, and their fluorescence properties, catalytic activities and Hirshfeld surface analyses were studied. [ABSTRACT FROM AUTHOR]

Four 3-(tetrazol-5-yl)-5-(pyrid-2-yl)-1,2,4-triazole (H2TPT) based complexes of [Co2(TPT)2(H2O)2] (1), [Mn2(TPT)2(H2O)2] (2), [Mn(TPT)(H2O)2]n (3) and [Cu(TPT)]n (4) have been solvothermally synthesized and structurally characterized by X-ray single-crystal diffraction analysis. Complexes 1 and 2 display isostructural dinuclear structures, while complex 3 exhibits a 1D zigzag chain structure. The structural difference for 2 and 3 may be caused by 100 and 160 °C temperature-controlled conditions. Complex 4 is a 3D framework structure in which the Cu2+ ion is in square pyramid coordination geometry. Complexes 1–4 display good thermal stability evaluated by thermogravimetric analysis. Complexes 1 and 4 show very strong antiferromagnetic interactions. The electrocatalytic oxygen evolution of complexes 1–4 was tested under neutral conditions, which revealed that the four complexes possess electrocatalytic oxygen evolution activity. Complex 1 exhibits a current density of 10.0 mA cm−2 at a potential of 2.00 V (vs. RHE), presenting 50-fold improvement in specific activity over the glassy carbon electrode. [ABSTRACT FROM AUTHOR]

Excellent photoelectrochemical activity was demonstrated for an easily prepared porous Ni-O/Ni/Si photoanode with an onset potential of 0.93 VRHE, a photocurrent of 39.7 mA cm−2 at 1.23 VRHE, an energy conversion efficiency of 3.2% and a stability above 100 h. [ABSTRACT FROM AUTHOR]

A new salicylaldehyde-based azo dye 5-azotriazolyl-3-methoxysalicylaldehyde (H2TMSA) and its two Ln3+ complexes {[Ln(HTMSA)3(H2O)2][Ln(HTMSA)3(DMF)(H2O)]}·15H2O (Ln = Dy(1) and Tb(2)) have been synthesized and characterized by IR, Raman, 1H NMR and single-crystal X-ray diffraction techniques. H2TMSA shows an azo form in acidic (pH ＜ 5.05) and strong basic (pH ＞ 12.41) conditions, and a pH-dependent azo-hydrazone tautomerism in the range of pH 5.05 to 12.41, which is demonstrated by the time-dependent density functional theory (TD-DFT) calculations. Single-crystal X-ray diffraction reveals that 1 and 2 are isostructural complexes in which the Ln3+ ions are surrounded by six oxygen atoms from three dichelate HTMSA− ligands and two oxygen atoms from two solvent molecules forming a distorted square-antiprismatic geometry. Complex 1 shows distinct slow magnetic relaxation under a zero dc field, while 2 displays field-induced slow magnetic relaxation. Ab initio calculations were performed on the two complexes to understand their magnetic anisotropy and their different magnetic dynamics. [ABSTRACT FROM AUTHOR]

Lowering the dimension of transition metal dichalcogenides is an efficient approach to expose more S-edge-sites. Here, zero-dimensional MoS2 and WS2 nanodots are successfully prepared with the assistance of a template of NiNi Prussian blue analogue nanoplates. The novel hybrids exhibit highly efficient and stable catalytic ability for the hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

Carbon nanodots (CDs) are novel forms of zero-dimensional carbonaceous nanomaterials, which have attracted the attention of researchers. Long wavelength emission decreases the interference of auto-fluorescence of tissue and can also penetrate more deeply. However, it is still a challenge to develop red emissive CDs. In this work, nitrogen, sulfur co-doped CDs are synthesized with red light emission through one-step solvothermal treatment. The as-synthesized CDs exhibit excellent properties such as high chemical stability, good biocompatibility, excellent photoluminescence properties, good water solubility, and low toxicity, and also show high sensitivity and selectivity towards Fe3+ sensing. The detection limit is as low as 17.3 nM. In addition, the CDs are successfully utilized for monitoring Fe3+ in living cells, which demonstrates their promising applicability in bioimaging. Furthermore, a test paper based on the CQDs has been prepared. This developed nanosensor can detect Fe3+ visually and sensitively without any further steps which will make a great contribution to the development of ion sensors. [ABSTRACT FROM AUTHOR]

A 4-amino-1,2,4-triazole (NH2-trz) based linear trinuclear Fe(ii) complex of [Fe3(NH2-trz)6(SCN)4(H2O)2](SCN)2·H2O (1) has been hydrothermally synthesized by the reaction of a NH2-trz ligand with FeSO4. A single crystal of complex 1 is able to extrude one lattice water and one coordinated water, leading to another single crystal of complex 1a with a formula [Fe3(NH2-trz)6(SCN)5(H2O)](SCN) by heating. Complex 1a can be reversed to 1 upon the reabsorption of water. Single-crystal X-ray diffraction analysis reveals that these two complexes consist of a linear trinuclear core where a central Fe1 ion is coordinated to six nitrogen atoms from six bridged NH2-trz ligands and one of the terminal Fe2 ions is coordinated to five nitrogen atoms and one oxygen atom. The terminal Fe3 ion in 1 coordinates to five nitrogen atoms and one oxygen atom; however, the terminal Fe3 ion in 1a coordinates to six nitrogen atoms. Magnetic susceptibility measurements demonstrate that they exhibited gradual spin crossover (SCO) for the central Fe(ii) ion; however, different spin transition temperatures were displayed for complexes 1 and 1a (T1/2 = 202 K for 1 and 160 K for 1a). These different spin transition temperatures arise from the different intermolecular hydrogen bonding interactions in the two complexes. [ABSTRACT FROM AUTHOR]

We studied the interfacial mechanical properties of polyelectrolyte multilayer assemblies of poly(diallylamine hydrochloride) (PAH) and poly(4-styrenesulfonate)sodium salt (PSS) at the air–water interface using axisymmetric drop shape analysis (ADSA) during hydrostatic inflation as a function of aqueous salt concentration and two different polyanion molecular weights (Mw∼ 13 and 70 kDa). Surface elastic moduli (Gs) ranged from 50 to 300 mN m−1. Using the measured film thickness, the bulk moduli (G) ranged from 10 to 90 MPa consistent with elastomeric solids. This solid-like interface was evidenced by a systematic departure of the inflated shape from the Young–Laplace equation, which assumes a liquid-like interface. Surface elastic moduli increased and bulk elastic moduli decreased with increasing nanomembrane transverse dimension, and multilayers with the lower molecular weight anion were more transversely compact than those of higher molecular weight and displayed a larger elastic modulus. The bulk moduli of both types of multilayer assemblies asymptotically approach a constant value for films with more than two bilayers of polyelectrolyte, consistent with the observed transition from a ’glassy‘ to ‘rubbery’ state. Both types of multilayer assemblies displayed plasticization with increasing sodium chloride concentration in the adjoining aqueous phase, i.e. saloplasticity, and exhibited a transition from elastic to plastic response to deformation. The restored mobility of the polyelectrolyte resulting from the shift from intrinsic to extrinsic charge complexation, restores fluidity to the interface and is evidenced by experimental observation of a liquid-like interface when loaded. The higher molecular weight polyanion multilayers plasticized at lower salt concentrations suggesting that the lower melting point of the higher molecular weight polyanion assembly is attributable to a lesser extent of electrostatic cross-linking underscoring the unconventional dependence of molecular weight on saloplasticity in strongly dissociated polyelectrolytes. [ABSTRACT FROM AUTHOR]

Si has been studied as a photocathode for water splitting; however, its commercial application is hindered by its poor stability and low solar-to-hydrogen conversion efficiency (η), where the effective loading of catalysts on the Si surface is one of the key factors. Herein, we report that uniform and small Pt nanoparticles (NPs) were successfully prepared on an n+p-Si pyramid surface by a cheap electroless deposition method using Pt salt, based on the hydrophilic character of SiO2. A high η of 10.5% was obtained under 100 mW cm−2 simulated solar illumination with a Pt loading of only 1 μg cm−2, due to the fact that the Pt NPs are small enough to avoid the optical loss of Si, are distributed uniformly on the light-trapping pyramid Si surface to ensure a large number of reaction sites for H2 production, and establish intimate contact with Si to facilitate carrier transfer. Finally, an ∼15 nm amorphous TiO2 layer covered on the Pt/n+p-Si using atomic layer deposition results in a superior stability over more than one week of continuous photoelectrochemical testing, while increasing its η to a high value of 10.8% due to the improvement of charge transfer from Pt to the electrolyte. Our findings emphasize the importance of the effective loading of the catalyst and protective layer on the Si photocathode, which subsequently makes the photoelectrochemical process both efficient and stable. [ABSTRACT FROM AUTHOR]

Herein, a highly stable luminescent heterometallic MOF, [NaEu2(TATAB)2(DMF)3]·OH (CTGU-7, H3TATAB = 4,4′,4′′-s-triazine-1,3,5-triyltri-m-aminobenzoic acid, DMF = N,N′-dimethylformamide, CTGU = China Three Gorges University), was synthesized. CTGU-7 crystallizes in a highly symmetric cubic framework with the pyrite-type topology, constructed from a novel Eu2Na trimeric cluster as a 6-connected node. Observably, this framework remains intact in a remarkably extensive environment such as in a common solvent and aqueous solutions. CTGU-7 is demonstrated to be the first known MOF for the selective detection of oridazole antibiotics. It also exhibits high selectivity and sensitivity for nitrophenol and benzyl alcohol. Thus, this material can potentially be used as a multi-responsive luminescent sensor. [ABSTRACT FROM AUTHOR]

Reversible crystal-to-crystal transformation between a linear trinuclear Fe(ii) complex [Fe3(NH2-trz)6(SCN)5(H2O)] (SCN)·4H2O (1, NH2-trz = 4-amino-1,2,4-triazole) and a 1D chain [Fe3(NH2-trz)6(SCN)5]n(SCN)n (1a) and the SCO behaviour change have been studied by X-ray single-crystal diffraction, magnetic measurements and DSC. Complex 1a exhibits one more SCO step at a low temperature. [ABSTRACT FROM AUTHOR]

A porous carbon layer was inserted between a BiFeO3 film and a Pt catalyst for efficient solar water splitting. A photocathodic current density of −235.4 μA cm−2 at 0 V versus RHE and an onset potential of 1.19 V versus RHE were obtained under 100 mW cm−2 Xe-lamp illumination. [ABSTRACT FROM AUTHOR]

Four hetero-bimetallic [ZnIILnIII] complexes with the general formula [Zn(L)(OAc)Ln(NO3)2] (Ln = Sm, Eu, Tb and Dy) were synthesized by the Salamo-type ligand H2L (6,6′-diethoxy-2,2′-[1,2-ethylenedioxybis(nitrilomethylidyne)]diphenol) with Zn(OAc)2·2H2O and Ln(NO3)3·6H2O (Ln = Sm, Eu, Tb and Dy), respectively. X-ray crystal diffraction analyses revealed that all the Zn(ii) atoms were penta-coordinated, adopting distorted square pyramidal geometries, and the Ln(iii) atoms were nona-coordinated, forming distorted tricapped trigonal prism geometries. In addition, three-dimensional supramolecular structures were assembled through intermolecular hydrogen-bond interactions. In the [ZnIILnIII] complexes, only [Zn(L)(OAc)Sm(NO3)2] showed obvious orange-red light emission under UV light due to the characteristic f–f transitions of Sm3+ ions, which meant that the ligand H2L could transfer energy from its excited state to the lowest excited state of the Sm3+ ion effectively. A decrease in the χMT value illustrated weak antiferromagnetic interaction exciting in the [Zn(L)(OAc)Tb(NO3)2] and [Zn(L)(OAc)Dy(NO3)2] complexes. [ABSTRACT FROM AUTHOR]

Colossal permittivity (CP) materials have many important applications in electronics but their development has generally been hindered due to the difficulty in achieving a relatively low dielectric loss. In this work, we report an In + Ta co-doped TiO2 material system that manifests high dielectric permittivity and low dielectric loss based on the electron-pinned defect-dipole design. The dielectric loss can be reduced down to e.g. 0.002 at 1 kHz, giving high performance, low temperature dependent dielectric properties i.e. εr ＞ 104 with tan δ ＜ 0.02 in a broad temperature range of 50–400 K. Density functional theory calculations coupled with the defect analysis uncover that electron-pinned defect dipoles (EPDDs), in the form of highly stable triangle-diamond and/or triangle-linear dopant defect clusters with well-defined relative positions for Ti reduction, are also present in the host material for the CP observed. Such a high-performance dielectric material would thus help for practical applications and points to further discovery of promising new materials of this type. [ABSTRACT FROM AUTHOR]

By utilizing symmetrical pentacarboxylate ligands, 3,5-di(2′,5′-dicarboxylphenyl)benzoic acid (H5L1) and 3,5-di(2′,4′-dicarboxylphenyl)benzoic acid (H5L2), two novel porous Zn-MOFs, [Zn5(μ3-H2O)2(L1)2]·3DMA·4H2O (CTGU-3) and [Zn3(μ3-OH)L2(H2O)3]·H2O (CTGU-4) have been synthesized under solvothermal conditions. CTGU-3 and CTGU-4 exhibit 3D microporous frameworks with flu and dia topologies and possess unique secondary building units [Zn5(μ3-H2O)2(RCO2)6] and [Zn3(μ3-OH)(RCO2)3], respectively. Such porous systems create a unique space or surface to accommodate Ag nanoparticles (Ag NPs), which could efficiently prevent Ag NPs from aggregation and leaching. In this work, two new Ag@Zn-MOF composites, denoted as Ag@CTGU, have been successfully fabricated through solution infiltration, for the reduction of nitrophenol. Compared with CTGU-4, CTGU-3 shows enhanced catalytic efficiency toward the reaction when it is used as a catalyst support of Ag NPs. Moreover, gas sorption and luminescence properties of two compounds were also investigated. [ABSTRACT FROM AUTHOR]

Three heterocyclic azo dyes of azotriazolyl-2,7-dihydroxynaphthalene (H3AD), azotetrazolyl-2-naphthol (H2ATN) and azotetrazolyl-2,7-dihydroxynaphthalene (H3ATD) have been synthesized and characterized by IR, Raman spectra, 1H, 13C NMR and X-ray single-crystal diffraction techniques and their azo–hydrazone tautomerism has been achieved by pH control and coordination-coupled proton transfer. UV-vis spectra have been used to monitor the pH-titration and metal-ion complex experiments for three solutions of H3AD, H2ATN and H3ATD and the analysis of their spectral data has provided a clear proof that the hydrazone form is the dominant tautomer in acidic and neutral solutions, while the azo form is the dominant one in alkaline solutions. Crystallographic data demonstrate that the neutral dyes exist as hydrazone tautomers but are changed to azo tautomers when they coordinate to metal ions. The time-dependent density functional theory (TD-DFT) calculations are used to demonstrate the UV-vis spectroscopic properties. [ABSTRACT FROM AUTHOR]

A super-stable multifunctional terbium(iii)–organic framework, namely {[Tb(TATAB) (H2O)2]·NMP·H2O}n (Tb-MOF, H3TATAB = 4,4′,4′′-s-triazine-1,3,5-triyltri-m-aminobenzoic acid, NMP = N-methyl-2-pyrrolidone) was synthesized. Tb-MOF exhibits a 2D sql structure with binuclear [Tb2(COO)4(H2O)4]2+ units as 4-connected nodes, and free water and NMP molecules are inserted between 2D layers through hydrogen-bonding interactions, forming a sandwich-type architecture. Observably, such a framework remains intact in a remarkable variety of environments such as common solvents and aqueous solutions with metal cations and inorganic anions, as well as with a pH ranging from 1 to 13. In particular, Tb-MOF can not only detect small organic molecules, metal cations and inorganic anions with high sensitivity and high selectivity, but also can accurately detect explosive 2-nitrophenol, 3-nitrophenol, 4-nitrophenol and 2,4,6-trinitrophenol in water. Its luminescence quenching response to Fe3+ and Cr2O72− ions can be explained in terms of the competitive absorption mechanism. In addition, the luminescence intensity of Tb-MOF is strongly correlated with the pH value in a pH range from 1 to 13. Thus, this material can be potentially used as a multi-responsive luminescent sensor. [ABSTRACT FROM AUTHOR]

Through the self-assembly of a Salamo-type ligand H2L (H2L = 1,2-bis(3-methoxysalicylideneaminooxy)ethane) with Ni(OAc)2·4H2O, Ln(NO3)3·6H2O (Ln(iii) = La(iii), Gd(iii), Tb(iii) and Dy(iii)) and Py (Py = pyridine) or 4,4′-bipy (4,4′-bipy = 4,4′-bipyridine) or H2bdc (H2bdc = terephthalic acid), nine new Ni(ii)–Ln(iii) heterometallic complexes [Ni(L)La(OAc)(NO3)2(Py)(CH3OH)]·CH3OH (1), [Ni(L)Dy(OAc)(NO3)2(Py)] (2), 1∞[Ni(L)La(NO3)3(4,4′-bipy)(CH3OH)] (3), 1∞[Ni(L)Tb(NO3)3(4,4′-bipy)] (4), [Ni(L)Dy(OAc)(NO3)2(4,4′-bipy)] (5), [{Ni(L)Ln(NO3)2(DMF)(CH3OH)}2(bdc)] (Ln = La (6) and Gd (7)) and [{Ni(L)Ln(NO3)2(DMF)}2(bdc)] (Ln = Tb (8) and Dy (9)) were obtained, respectively. The acetato ligand bridges the Ni(ii) and Ln(iii) (Ln = La (1) and Dy (2)) atoms in a μ2 fashion and the Py coordinates to the apical position by a nitrogen atom in the heterobimetallic complexes 1 and 2. Complexes 3 and 4 are 1D coordination polymers constructed from heterobimetallic [Ni(L)Ln] (Ln = La (3) and Tb (4)) units which are connected by the exo-dentate ligand 4,4′-bipy bearing nitrogen-donor atoms, but complex 5 is a heterobimetallic Ni(ii)–Dy(iii) complex which is prepared under the same reaction conditions as complexes 3 and 4. Four heterotetranuclear dimers were constructed from heterobimetallic [Ni(L)Ln] (Ln = La (6), Gd (7)), Tb (8) and Dy (9) units which are connected by the exo-dentate H2bdc ligand with oxygen-donor atoms. Magnetic measurements were performed on the Gd(iii), Tb(iii) and Dy(iii) complexes. [ABSTRACT FROM AUTHOR]

Various erbium ion-exchanged montmorillonite K10 materials were prepared by an ion exchange method and were found to act as efficient solid acid catalysts. The catalytic materials synthesized in this work were characterized using a combination of X-ray fluorescence spectroscopy, N2 adsorption, powder X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR), inductively coupled plasma optical emission spectroscopy, X-ray photoelectron spectroscopy and NH3 temperature-programmed desorption, as well as by FT-IR spectra analysis following pyridine adsorption. These catalysts were also evaluated with regard to the hydrothermal conversion of cellulose to lactic acid. Lactic acid yields as high as 67.6% were obtained when reacting 0.3 g cellulose, 0.1 g catalyst and 30 mL water at 240 °C under 2 MPa N2 for 30 min. Upon recycling of the catalyst, the lactic acid yields decreased from 67.6 to 58.7 to 55.9% during the first, second and third trials. Beginning with the second trial the catalyst behaved as a true heterogeneous catalyst for the conversion of cellulose to lactic acid. The observed decreases in catalytic activity during recycling could be due to a combination of erbium ion leaching, deposition of carbon species in pores and partial structural changes in the catalyst. [ABSTRACT FROM AUTHOR]

Presented here are two novel (3,6)-connected porous metal–organic frameworks (MOFs) formulated as [Co3(BPT)2(DMF)(bpp)]·DMF (1) and [(CH3)2NH2][Cu(BPT)]·DMF·2H2O (2) (H3BPT = biphenyl-3,4′,5-tricarboxylic acid, bpp = 1,3-bis(4-pyridyl)propane). Compound 1 has a 3D neutral framework decorated with one-dimensional hydrophobic channels (diameter 8.778(7) Å) while compound 2 has an anionic framework containing one-dimensional hydrophilic channels with a diameter of 8.688(5) Å. Interestingly, compound 1 shows promising visible-light-driven photocatalytic activity for the degradation of RhB while compound 2 exhibits high intake capacities for CO2 (11.90 wt%) and H2 (1.23 wt%), respectively. In addition, temperature-dependent magnetic susceptibility measurements indicated that both 1 and 2 display dominant antiferromagnetic coupling among the adjacent Co(ii)/Cu(ii) centers. [ABSTRACT FROM AUTHOR]

A novel approach for the direct synthesis of a 1,2,4-triazine core starting from eight azo conjugated aromatic compounds, 5-azo-(1,2,4-triazolyl) salicylic acid, 5-azo-(3-methyl-1,2,4-triazolyl) salicylic acid, 5-azo-(3-carboxyl-1,2,4-triazolyl) salicylic acid, 5-azo-(1,2-pyrazolyl) salicylic acid, 4-azo-(1,2,4-triazolyl) phenol, 4-azo-(3-carboxyl-1,2,4-triazolyl) phenol, 4-azo-(1,2-pyrazolyl) phenol, and 5-azo-(1,2,4-triazolyl) acetylsalicylic acid, via transition or lanthanide metal catalyzed intramolecular C–H/N–H functionalization and C–N bond formation has been developed under one-step hydrothermal synthetic conditions. [ABSTRACT FROM AUTHOR]

A rational design strategy of novel fluorophores for luminescent down-shifting (LDS) application was proposed and tested in this paper. Three new fluorophores (1a–c) with specific intramolecular charge transfer (ICT) and aggregation-induced emission (AIE) characteristics were synthesized as LDS molecules for increasing the output short circuit current density (Jsc) of a CdTe solar cell. Photophysical studies of their solution and solid states, and photovoltaic measurements of their PMMA solid films applied on a CdTe solar cell suggested that the specific spectroscopic properties and Jsc enhancement effects of these molecules were highly related to their chemical structures. The Jsc enhancement effects of these fluorophores were measured on both a CdTe small cell and a large panel. An increase in the output Jsc by as high as 5.69% for a small cell and 8.88% for a large panel was observed. Compared to a traditional LDS molecule, Y083, these fluorophores exhibited more superior capabilities of LDS. [ABSTRACT FROM AUTHOR]

Pb(Zr,Ti)O3 (PZT) film with a band gap of 3.6 eV was prepared on In2O3:Sn (ITO) coated glass, and then an amorphous silicon (a-Si) film with a narrow band gap of 1.8 eV was deposited on the PZT/ITO/glass. The short-circuit current of Ag/a-Si/PZT/ITO/glass sample is 2.56 mA cm−2, about 50 times greater than that of Pt/PZT/ITO/glass sample. The energy level of the a-Si film is well matched with that of PZT film, which is beneficial to the transport of UV-visible light-induced charges in the Ag/a-Si/PZT/ITO/glass sample. The photovoltaic output can be tuned by changing the dopant type of the a-Si film, and the maximum photoelectric conversion efficiency is measured to be up to 1.25% in the PZT film with an n-type a-Si film (phosphorus doped). [ABSTRACT FROM AUTHOR]

We developed a pulsed current deposition method to fabricate TiO2 inverse opals with highly dispersed Ag nanoparticles (NPs) as a visible light driven plasmonic photocatalyst. It is observed that the incorporation of Ag NPs can significantly improve the photocatalytic activity of TiO2 inverse opals in the visible light region. The sample with a deposition time of 45 s has the highest measured photocatalytic activity, and exceeds that of the Ag/TiO2 inverse opals prepared by a photochemical reduction method. Such an enhancement is ascribed to the optimized localized surface plasmon resonance property of the Ag NPs, and excellent separation of the photoexcited electrons and Ag+ ions, resulting from the uniform Ag NPs produced by pulsed current deposition. The proposed mechanism is further confirmed by hydroxyl radical detection and electrochemical impedance spectroscopy analysis. Our study provides new insight into the design and preparation of advanced visible light photocatalytic materials. [ABSTRACT FROM AUTHOR]

Six 3,3′-azobis-1,2,4-triazole (H2ABT) complexes [Mn2 (ABT)(bpy)4(H2O)2]·(ABT)·4H2O (1), [Mn(ABT)(H2O)4]·H2O (2), [Co(ABT)(en)2]·(H2ABT)·2H2O (3), [Cd(ABT)0.5(en)2]·(ABT)0.5·2H2O (4), [Zn(ABT)0.5(en)2]·(ABT)0.5·2H2O (5), [Cu(ABT)0.5(en)2]·(ABT)0.5 (6), where en = ethylenediamine, bpy = 2,2-bipyridine, have been synthesized and characterized by single crystal X-ray diffraction analysis. In complexes 1–6, the unusual face-to-face π–π stacking interactions among heterocyclic aromatic rings and three kinds of hydrogen bonds C–H…O, N–H…O and O–H…O are observed. The π–π stacking, hydrogen bonding and electrostatic interactions are responsible for the stabilization of these 2D and 3D supramolecular structures. The aqueous solutions of 1–6 with the concentration of 6 × 10−5 mol dm−3 show photochromism. The fluorescent properties of solid-state samples of 1–6 have been investigated. The π–π stacking interaction energies for 1–6 were calculated at MP2 level using Gaussian 09 suite and demonstrated. [ABSTRACT FROM AUTHOR]

Lanthanide triflates are excellent catalysts for the hydrothermal conversion of cellulose to lactic acid. Under the optimum conditions, as high as 89.6% yield of lactic acid was obtained by using Er(OTf)3 as the catalyst. This catalyst could be reused at least five times without obvious loss of activity. [ABSTRACT FROM AUTHOR]

Two new MnII supramolecular isomers, [Mn2(pbt)2(H2O)2·2H2O]n (1) and [Mn2(pbt)2(H2O)2·DMF]n (2) (H2pbt = 5′-(pyridin-2-yl)-2H,4′H-3,3′-bi(1,2,4-triazole), DMF = N,N-dimethylformamide), have been solvothermally synthesized in different solvent systems. Compound 1 exhibits a (3,4)-connected net with the point symbol of (6.82)4(62.82.102), whereas 2 exhibits a rare 3D lvt-42·84 net. Moreover, an irreversible solid-state transformation from 2 to 1 was observed, and their magnetic properties were also investigated and discussed in detail. [ABSTRACT FROM AUTHOR]

Two unique six-connected self-penetrating coordination polymers with a new (44.610.8) network topology, derived from the cross-linking of two 66-diasubnets, were constructed from NiIIor CoIIand two types of V-shaped tectons. The NiIIcomplex 1shows an antiferromagnetic coupling viaμ-carboxylate and μ-H2O pathways, whereas the CoIIcomplex 2exhibits the single-ion behavior in 300–34 K and then a ferromagnetic coupling at lower temperatures. [ABSTRACT FROM AUTHOR]