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The analysis of the 1H NMRD profiles and 17O NMR data recorded for the Gd(iii) complexes evidences that water exchange is modulated by the ability of peripherical substituents to establish hydrogen bonds with the coordinated and/or second sphere water molecules. DFT calculations were used to model the transition states responsible for the dissociative water exchange mechanism, providing support to the crucial role of hydrogen-bonds in accelerating water exchange.Mn(iii) complexes with achiral ligands, (E)-N-(2-((2-aminobenzylidene)amino)-2-methylpropyl)-5-X-2-hydroxybenzamide (HLX, X = H, Cl, Br, and I), crystallise as chiral conglomerates containing amide oxygen-bridged one-dimensional coordination polymers that exhibit weak ferromagnetism. The bulk products exhibit symmetry breaking in that they do not contain equal amounts of enantiomers, though which is the dominant species depends on the substituent X.Herein, a 7.35 wt% Co loading C-SAC is synthesized by pyrolysis of Co-MOF-74 in a strongly polar molten salt system. In dye-sensitized solar cells, this SAC based counter electrode shows higher photoelectric conversion efficiency than the Pt counter electrode. This work provides new insights for the preparation and application of C-SACs.Today, it is extremely urgent to face the increasing shortage of clean and safe water resources, determined by the exponential growth of both world population and its consumerism, climate change and pollution. Water remediation from traditional chemicals and contaminants of emerging concerns (CECs) is supposed to be among the major methods to solve water scarcity issues. Reverse osmosis (RO) and nanofiltration (NF) membrane separation technologies have proven to be feasible, sustainable and highly effective methods for the removal of contaminants, comprising the extremely persistent and recalcitrant perfluoroalkyl substances (PFASs), which failed to be treated through the traditional water treatment approaches. So far, however, they have been unable to assure PFASs levels under the established guidance limits for drinking water and still suffer from fouling problems, which limit their large-scale application. Novel configurations, improvement in process design and the development of high-performant materials ogress RO and NF technology for water remediation.A series of novel non-gallate near-infrared long-persistent phosphorescence Mg2-xZnxSnO4Cr3+ phosphors were synthesized, and their structure and luminescence properties were investigated systematically. Under 448 nm blue light excitation, all the phosphors exhibit a broad emission band centered at 730 nm and a shoulder peak at 708 nm, which are attributed to the 4T2(4F) → 4A2 and 2E → 4A2 transitions of Cr3+, respectively. The excitation spectra of the samples clearly show the characteristic excitation of Cr3+ in the octahedral crystal field, with three obvious peaks at 324, 448 and 620 nm respectively. The phosphor with a composition of Mg1.4Zn0.6SnO40.03Cr3+ shows the strongest photoluminescence intensity which is 2.87 times and 3.09 times that of Mg2SnO40.03Cr3+ and Zn2SnO40.03Cr3+, respectively. Besides, all the samples show intense near-infrared long-persistent phosphorescence. For the optimized sample Mg1.4Zn0.6SnO40.005Cr3+, its phosphorescence can still be observed with a night vision instrument 18 h after removing the 365 nm UV light source. Finally, a feasible phosphorescence mechanism of the Mg1.4Zn0.6SnO4Cr3+ phosphor was proposed and discussed. This study may provide a new method for developing novel near-infrared long-persistent phosphorescence phosphors through crystal structure modification.To ascertain the influence of binary ligand systems [1,1-dicyanoethylene-2,2-dithiolate (i-mnt-2) and polyamine tetraen = tris(2-aminoethyl)amine, tren = diethylene triamine and opda = o-phenylenediamine] on the coordination modes of the Ni(ii) metal center and resulting supramolecular architectures, a series of nickel(ii) thiolate complexes [Ni(tetraen)(i-mnt)](DMSO) (1), [Ni2(tren)2(i-mnt)2] (2), and [Ni2(i-mnt)2(opda)2]n (3) have been synthesized in high yield in one step in water and structurally characterized by single crystal X-ray crystallography and spectroscopic techniques. X-ray diffraction studies disclose the diverse i-mnt-2 coordination to the Ni+2 center in the presence of active polyamine ligands, forming a slightly distorted octahedral geometry (NiN4S2) in 1, square planar (NiS4) and distorted octahedral geometries (NiN6) in the bimetallic co-crystallized aggregate of cationic [Ni(tren)2]+2 and anionic [Ni(i-mnt)2]-2 in 2, and a one dimensional (1D) polymeric chain along the [100] axis in 3, having consecutive square planar (NiS4) and octahedral (NiN6) coordination kernels. The N-HO, N-HS, N-HN, N-HS, N-HN, and N-HO type hydrogen bonds stabilize the supramolecular assemblies in 1, 2, and 3 respectively imparting interesting graph-set-motifs. The molecular Hirshfeld surface analyses (HS) and 2D fingerprint plots were utilized for decoding all types of non-covalent contacts in the crystal networks. Atomic HS analysis of the Ni+2 centers reveals significant Ni-N metal-ligand interactions compared to Ni-S interactions. We have also studied the unorthodox interactions observed in the solid state structures of 1-3 by QTAIM and NBO analyses. Moreover, all the complexes proved to be highly active water reduction co-catalysts (WRC) in a photo-catalytic hydrogen evolution process involving iridium photosensitizers, wherein 2 and 3 having a square planar arrangement around the nickel center(s) - were found to be the most active ones, achieving 1000 and 1119 turnover numbers (TON), respectively.In this work, an efficient and facile strategy has been adopted for the stepwise synthesis of the RGO-MSiO2/PdO hybrid nanomaterial (HY-NM). Herein, a hybrid nanostructure of mesoporous silica over graphene oxide (GO) sheets has been developed followed by immobilizing palladium oxide nanoparticles (PdO NPs), and then it has been utilized for catalyzing a multicomponent reaction (MCR). To authenticate the successful synthesis of the HY-NM and successive immobilization of PdO NPs, various physicochemical characterization techniques were utilized such as SEM, EDAX, HR-TEM, HR-XRD, TGA, BET, FT-IR, and XPS analysis. The activity of the HY-NM has been determined by performing the catalyst-mediated synthesis of β-substituted indole derivatives (yield 90-98%). The excellent catalytic activity of the prepared HY-NM could be observed due to its high surface area and large porosity, which facilitates the penetration and interaction of reactant molecules with the catalytic active species. This protocol eliminates the requirement of further purification after the isolation of the product from the reaction mixture. The ease of handling, recyclability of the catalyst, and simple work-up procedure are the main features of this protocol. The synthesized HY-NM could be recycled for multiple catalytic cycles making it a very effective heterogeneous catalyst.This computational study presents the molecular conduction properties of two members of the polyoxovanadate (POV) class of molecules, V6O19 (Lindqvist-type) and V18O42, which have been targeted as possible successors of the materials that are currently used in complementary metal-oxide semiconductor (CMOS) technology. Molecular conductivity calculations on the Lindqvist-type POV absorbed on Au(111) shows a staircase conductivity as function of the applied bias voltage, which is directly related to the oxidation state of the absorbed molecule. After these proof-of-principle calculations we applied the same technique to the larger V18O42, a system featuring many more easily attainable redox states, and hence, in principle even more interesting from the multiple-state resistive (memristive) viewpoint. selleck inhibitor The calculated transmission strongly suggests that this molecule does not possess staircase conductivity, a fact ascribed to the large number of unpaired electrons in the resting state.Lithium-sulfur batteries have a high theoretical energy density but they need better sulfur host materials to retain the lithium polysulfide shuttle effect, which results in the batteries' capacity fading. Titanium carbide MXene (Ti3C2Tx MXene) is an excellent host for the sulfur cathode because of its layered-stacked structure and many surface termination groups. The sulfur content in S/Ti3C2Tx MXene composites is an important factor affecting the cathodes' electrochemical performance. In this work, S/Ti3C2Tx MXene composites with different sulfur contents are prepared by a one-step hydrothermal process, and the influence of the sulfur content in the S/Ti3C2Tx MXene composite on the S/Ti3C2Tx MXene cathode's electrochemical performance is studied. When the mass ratio of sulfur to MXene in the reactant is 4  1, the sulfur nanoparticles are uniformly filled in the layered-stacked structure. The layered-stacked structure can buffer the volume expansion of sulfur during cycling and the surface termination groups exhibit strong adsorption of LiPSn. Thus, the S/MXene composite with an optimum sulfur content (67.0 wt%) demonstrates an excellent electrochemical performance, including a high initial reversible capacity (1277 mA h g-1 at 0.5 C) and the best cycling performance (1059 mA h g-1 at 0.5 C after 100 cycles). This work offers a guide to developing advanced S-based cathode materials with an appropriate S content for lithium sulfur batteries.Oxygen electroreduction (ORR) via a two-electron pathway is a promising alternative for hydrogen peroxide (H2O2) synthesis in small-scale applications. In this work, nitrogen and sulfur co-doped carbon coated zinc sulfide nanoparticles (ZnS@C) are synthesized using facile high-temperature annealing. In an alkaline electrolyte, the presence of ZnS suppresses the reduction of H2O2 during the ORR and contributes to high H2O2 selectivity (∼90%) over a wide potential range (0.40-0.80 V). Continuous generation of H2O2 is in turn achieved at an outstanding rate of 1.485 mol gcat.-1 h-1 with a faradaic efficiency of 93.7%.In order to harvest more light wavelengths to improve the light-assisted electrochemical water splitting capacity, we developed a novel heterostructure of three-dimensional (3D) flower-like CuS architecture with accompanying SnS2 nanoparticles and reduced graphene oxide (rGO) aerogel for outstanding light-assisted electrocatalytic OER performance and good stability. The excellent catalytic kinetics, effective capturing of visible light, and rapid charge transfer of the CuS/SnS2/rGO (CSr) heterostructure were demonstrated. The overpotential (264 mV@10 mA cm-2) under light-assisted conditions is 20% lower than that under light-chopped conditions. SnS2 can harvest more light wavelengths and this boosts its intrinsic activity. However, with the increase of the SnS2 content, the OER activity decreases. The combination of the CS heterostructure and the rGO conductive aerogel achieves rapid charge transfer. Furthermore, the possible mechanism of the light-assisted electrocatalytic OER was also proposed. Overall, this work provides new insights into the simple and scalable fabrication of a highly efficient, low-cost, and stable non-noble-metal-based electrocatalyst.