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By utilizing DFT calculations and AIMD simulations, we systematically investigated the photocatalytic activity of B/N2V-pg-C3N4, which is coplanar g-C3N4 with an electron-deficient B atom substituted for the nitrogen atom, for CO2 reduction. Significantly, electronic structure analysis revealed that compared with pristine pg-C3N4 (Eg = 2.98 eV), B/N2V-pg-C3N4 had a smaller band gap (Eg = 1.70 eV), where the position of the conduction band minimum (CBM) and valence band maximum (VBM) increased by approximately 0.79 eV and decreased by approximately 0.49 eV, respectively. Catalytic mechanism studies demonstrated that by comparison with the barrier of 1.55 eV in the hydrogen evolution reaction (HER), B/N2V-pg-C3N4 thermodynamically tended to catalyse CO2 into HCOOH (Ea = 0.86 eV) and HCHO (Ea = 0.86 eV) with high selectivity. Further, isotope effect calculations revealed that B/N2V-pg-C3N4 is an excellent catalyst for the synthesis of deuterium products using CO2. Thus, the activation of CO2 in B/N2V-pg-C3N4 is dictated by the curved geometry and its unique electronic-deficient p states, which are beneficial for its excellent photocatalytic performance for CO2 reduction. [ABSTRACT FROM AUTHOR]

Two new metal-organic frameworks (1-2) were ionothermally obtained by the reaction of a biphenyltetracarboxylic sodium (Na4BPTC) ligand and M(OOCCH3)2 (M = Co(1) and Mn(2)). Crystal structure analysis reveals that 1 is a Co3Na6 unit-based three dimensional heterometallic MOF, while 2 exhibits a {Mn-(COO)n} chain-based three-dimensional framework. Furthermore, the magnetic measurement shows that both of them have anti-ferromagnetic properties. A combination of Density Functional Theory (DFT) and Quantum Monte Carlo (QMC) simulation uncovers that in 2 the coupling parameters between two adjacent Mn(II) ions are J1 = -2.0 cm-1 and J2 = -1.6 cm-1, and the magnetism mainly originates from the propagation of Mn(II) ions by the super-exchange of carboxylates. Interestingly, the superexchange modes of J1 and J2 are different. Two spin nets of -/+/-dominate in the coupling for J1, while for J2 there are two spin nets of -/+/- and one spin net of +/-/+. [ABSTRACT FROM AUTHOR]

A series of new lanthanide-based metal-organic frameworks were prepared by the reaction of H2EDA ligand and Ln(NO3)3 (H2EDA = (ethylenedithio)acetic acid, Ln = La (1, 5), Nd (2), Eu (3) and Gd (4)). 1-4 exhibit three-dimensional isomorphic structures, while 5 displays a different framework than 1-4. It was found that the structures of the lanthanide MOFs are easyly influenced by the reaction conditions and the metal ion radius. Moreover, the emission spectra revealed that 3 exhibits good luminescence properties. Magnetism measurements showed that 4 has ferromagnetic properties. Quantum Monte Carlo (QMC) simulations revealed that the coupling parameter between two Gd(III) ions is 0.03 cm-1, suggesting a weak ferromagnetic exchange. Furthermore, under the consideration of strong correlations between localized f electrons, first principle density functional theory (DFT) calculations with the GGA + U approach showed that the magnetic properties of 4 are originated from the 4f electrons of Gd(III) propagating by a super-exchange pathway on two -/+/- spin nets of the carboxylate groups. [ABSTRACT FROM AUTHOR]

A series of lanthanide coordination polymers have been synthesized through the hydrothermal reaction of 2,5-piperazinedione-1,4-diacetic acid (H2PODC) and Ln(NO3)3(Ln = La, 1; Pr, 2; Sm, 3; Ho, 4and Er, 5). Crystal structure analysis reveals that their structural variations are attributed to the effect of lanthanide contraction. [ABSTRACT FROM AUTHOR]

The nature and properties of Pt surfaces in contact with pure water in PEM-H2O reactors were mimetically studied by employing CV measurements with microelectrode techniques. These “Pt/water” interfaces were found to be electrochemically polarizable, and the local interfacial potential relative to reversible hydrogen electrode (RHE) potential in pure water is numerically the same as the potential value measured against a RHE in contact with PEM as the reference electrode. However, the structural parameters of the electric double layer at the “Pt/water” interfaces can be quite different from those at the “Pt/PEM” interfaces, and the kinetics of electrode processes could be seriously affected by the structure of electric double layer in pure water media. Besides, there is active diffusional flow of intermediates of electrode reactions between the “Pt/water” and the “Pt/PEM” interfaces, thus facilitating the active involvement of the “Pt/water” interfaces in the current-generation mechanism of PEM fuel cells and other types of PEM-H2O reactors. [ABSTRACT FROM AUTHOR]

A 3D metal–organic framework, featuring three kinds of cation channels, was obtained through an ionothermal reaction. Investigation on its temperature-dependent conductivity indicates the contribution of order and disorder of the Emim+(Emim+= 1-ethyl-3-methyl imidazolium bromide) in the channel to its conductivity. [ABSTRACT FROM AUTHOR]

We report a specially designed alkaline polymer electrolyte (APE) with extraordinary stability in both physical and chemical properties, which enables applications of fuel cells and electrolysis at elevated temperatures. [ABSTRACT FROM AUTHOR]

A nanosized Gd6Ni3cluster-based two-dimensional 3d–4f heterometallic coordination polymer has been synthesized under hydrothermal conditions using a mixture of H4PMIDA (H4PMIDA = N-(phosphonomethyl) iminodiacetic acid), Gd(ClO4)3and Ni(CH3COO)2·4H2O. An electrical property investigation reveals that the coordination polymer exhibits a proton conductivity. [ABSTRACT FROM AUTHOR]

The anisotropy of polarization in a 1D copper(II)-based coordination polymer was investigated experimentally and theoretically for the first time, revealing that the origin of the ferroelectricity and its anisotropic nature are closely related to the coordination geometry of the metal ion and the packing mode of the coordination polymer. [ABSTRACT FROM AUTHOR]

The reaction of iminodiacetic acid with Ln2O3 (Ln = Dy, Ho, Er, Yb) under hydrothermal conditions generate a series of 3D lanthanide-based coordination polymers, in which, the iminodiacetic acid (IDA) was transformed into a 2,5- diketopiperazine-1,4-diacetate. [ABSTRACT FROM AUTHOR]

The reaction of iminodiacetic acid with Ln2O3(Ln = Dy, Ho, Er, Yb) under hydrothermal conditions generate a series of 3D lanthanide-based coordination polymers, in which, the iminodiacetic acid (IDA) was transformed into a 2,5-diketopiperazine-1,4-diacetate. [ABSTRACT FROM AUTHOR]