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It is still a great challenge to achieve high selectivity of CH4 in CO2 electroreduction reactions (CO2RR) because of the similar reduction potentials of possible products and the sluggish kinetics for CO2 activation. Stabilizing key reaction intermediates by single type of active sites supported on porous conductive material is crucial to achieve high selectivity for single product such as CH4. Here, Cu2O(111) quantum dots with an average size of 3.5 nm are in situ synthesized on a porous conductive copper‐based metal–organic framework (CuHHTP), exhibiting high selectivity of 73 % towards CH4 with partial current density of 10.8 mA cm−2 at −1.4 V vs. RHE (reversible hydrogen electrode) in CO2RR. Operando infrared spectroscopy and DFT calculations reveal that the key intermediates (such as *CH2O and *OCH3) involved in the pathway of CH4 formation are stabilized by the single active Cu2O(111) and hydrogen bonding, thus generating CH4 instead of CO. [ABSTRACT FROM AUTHOR]

Abstract: High-quality single crystals of RbInS2, CsInS2 were isolated from the halide flux as a major phase of the repeated fusion of CaS and In2S3 followed by slow cooling. RbInS2 and CsInS2 are practically isostructural with KInS2. RbInS2: C2/c, a =11.071(6)Å, b =11.068(1)Å, c =15.610(7)Å, β =100.36(3)°, V =1882(2)Å3, Z =16, d x =3.74g/cm3, R =6.38%, R w =6.42%. CsInS2: C2/c, a =11.197(3)Å, b =11.158(3)Å, c =16.358(4)Å, β =99.92(2)°, V =2013(2)Å3, Z =16, d x =4.12g/cm3, R =5.60%, R w =6.20%. The AInS2 (A=Rb, Cs) structure is characterized by double layers of vertex-sharing [In4S10] units that each consists of four [InS4] polyhedra. The charge-balancing alkali-metal cations are stuffed into the channels created by the packing of these anionic [In4S10] blocks. The optical reflectance measurements show a band gap of 3.3eV for RbInS2 and 3.4eV for CsInS2, suggesting that both are semiconductors. [Copyright &y& Elsevier]

It is still a great challenge to achieve high selectivity of CH 4 in CO 2 electroreduction reactions (CO 2 RR) because of the similar reduction potentials of possible products and the sluggish kinetics for CO 2 activation. Stabilizing key reaction intermediates by single type of active sites supported on porous conductive material is crucial to achieve high selectivity for single product such as CH 4 . Here, Cu 2 O(111) quantum dots with an average size of 3.5 nm are in situ synthesized on a porous conductive copper-based metal-organic framework (CuHHTP), exhibiting high selectivity of 73 % towards CH 4 with partial current density of 10.8 mA cm -2 at -1.4 V vs. RHE (reversible hydrogen electrode) in CO 2 RR. Operando infrared spectroscopy and DFT calculations reveal that the key intermediates (such as *CH 2 O and *OCH 3 ) involved in the pathway of CH 4 formation are stabilized by the single active Cu 2 O(111) and hydrogen bonding, thus generating CH 4 instead of CO., (© 2020 Wiley-VCH GmbH.)

A series of nanoporous frameworks constructed by a polycatenated isoreticular 1D ribbon of rings have been developed. The orientation of catenated ribbons can be fine tuned by varying counter anions, which allows both pore size and shape to be systematically adjusted in a pre-synthetic process. Distinct from conventional pore construction modes in which the organic linkers are alternately connected by metal nodes into a 3D periodic arrangement, the present polycatenation approach represents an alternative for constructing soft porous materials with tunable pore metrics and functions. Furthermore, these porous structures can interconvert into each other based on an anion-exchange process, accompanied by the transformation of the interpenetrating structures in different dimensional networks, which is unusual in porous frameworks. In addition, such a porous framework can be post-synthetically modified by a photoinduced [2+2] cycloaddition reaction, which not only achieves the surface modification (from conjugated to non-conjugated inner surface), but also triggers the structural transformation from low dimension to high dimension. Such a post-modification process reinforces the pore architecture through a covalent locking effect and has a great impact on the adsorption properties., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A series of metal-organic frameworks based on a flexible, highly charged Bpybc ligand, namely 1⋅Mn⊃OH(-), 2⋅Mn⊃SO(4)(2-), 3⋅Mn⊃bdc(2-), 4⋅Eu⊃SO(4)(2-) (H(2)BpybcCl(2) = 1,1'-bis(4-carboxybenzyl)-4,4'-bipyridinium dichloride, H(2)bdc = 1,4-benzenedicarboxylic acid) have been obtained by a self-assembly process. Single-crystal X-ray-diffraction analysis revealed that all of these compounds contained the same n-fold 2D→3D Borromean-entangled topology with irregular butterfly-like pore channels that were parallel to the Borromean sheets. These structures were highly tolerant towards various metal ions (from divalent transition metals to trivalent lanthanide ions) and anion species (from small inorganic anions to bulky organic anions), which demonstrated the superstability of these Borromean linkages. This non-interpenetrated entanglement represents a new way of increasing the stability of the porous frameworks. The introduction of bipyridinium molecules into the porous frameworks led to the formation of cationic surface, which showed high affinities to methanol and water vapor. The distinct adsorption and desorption isotherms of methanol vapor in four complexes revealed that the accommodated anion species (of different size, shape, and location) provided a unique platform to tune the environment of the pore space. Measurements of the adsorption of various organic vapors onto framework 1⋅Mn⊃OH(-) further revealed that these pores have a high adsorption selectivity towards molecules with different sizes, polarities, or π-conjugated structures., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The batch sorption methods were employed to investigate the sorption behavior of tetracycline (TC) on the activated sludge. It was shown that the mixed liquor suspended solids (MLSS) and the initial concentration of TC had great impacts on equilibrium time, adsorption capacity and adsorption rate. Compared with pseudo first-order model, pseudo second-order model showed the better agreement. At 10, 25 degrees C, the Langmuir model was the best isotherm to describe the experimental data for adsorption of TC on activated sludge, and the maximum adsorption capacities were 31.14, 70.95 mg x g(-1) respectively; at 40 degrees C, the linear isotherm confirmed the agreement. The data were also modeled by D-R isotherm to determine the type of adsorption. At 10 degrees C (E was 9.13 kJ x mol(-1)), the dominant type was physical, and at 40 degrees C (E was 7.07 kJ x mol(-1)), the dominant type was chemical. With the temperature increasing, the adsorption capacity increased. Ion exchange is one mechanism for adsorption of TC on activated sludge. When the initial concentrations of TC were 5, 10, 20 mg x L(-1), with the Na+ concentration increasing from 0 mol x L(-1) to 0.1 mol x L(-1), the adsorption capacities decreased by 15.32%, 15.00%, 20.12% respectively. The maximum adsorption capacity was got at pH 6 when pH varied from 5 to 10.

Multi-spectroscopy, such as FTIR, dispersive Raman spectroscopy and UV-Vis, was applied to characterize the blue gel pen inks on paper at the time in the present study. Twenty eight collected blue gel pens with different brands and serials were separated into four different classes by different absorptions or Raman shift. Composition changing of blue gel pen inks on paper during artificial ageing was studied via TD-MS as well. The advantage and disadvantage of this spectroscopy used in analyzing and identifying blue gel pen inks on paper, and the potential application in the research on relative and absolute ageing of documents were discussed.

If the authors use normal infrared spectrometry, a lot of mixture compounds are difficult to characterize, because most of the peaks are overlapped in the spectra. Gas chromatography/Infrared spectrometry (GC-IR) are widely used in the separation and identification of organic complexes. The GC-IR can characterize the ingredients quickly and correctly that are difficult to do for normal infrared spectrometry. The technique also can be used to quantitatively analyze the ingredients by integral. The authors studied an unknown complex by GC-IR here.

The cluster compounds with d9-d9 magnetic system were investigated because of their magnetic character. Some of the copper(II) compounds with terephthalato as bridged unit, [{Cu(bipy) [C6H4(COO)2]}2.H2O]n and [Cu(phen) [C6H4(COO)2]]n, have been synthesized through a solvothermal reaction, and their crystal structures have been determined by X-ray diffraction. Their shape looks like zigzag-chain. In this paper, the molecular vibration spectra of the title complexes have been studied in detail. The middle and far-infrared spectra, and Raman spectra of the compounds have been reported and their assignments have been made experientially. The characteristic carbonyl absorption of terephthalato group at 1688 cm(-1) disappeared while the complexes formed. The characteristic peaks of COO- group were splited into two peaks respectively that appeared at 1603, 1574 cm(-1) (vasCOO) and 1369, 1356 cm(-1) (vsCOO) in [{Cu(bipy)[C6H4(COO)2]}2.H2O]n, and at 1614, 1605 cm(-1) (vasCOO) and 1373, 1344 cm(-1) (vsCOO) in [Cu(phen) [C6H4(COO)2]]n. The relationship between the structures of the compounds and the spectra has been discussed as well. The coincidence between experiential assignments and the theoretic calculation will be confirmed.