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Metal-organic frameworks (MOFs) represent an emerging class of platforms to assemble single site photocatalysts for artificial photosynthesis. read more In this work, we report a new CO2 reduction photocatalyst (UiO-68-Fe-bpy) based on a robust Zr(iv)-MOF platform with incorporated Fe(bpy)Cl3 (bpy refers to the 4'-methyl-[2,2'-bipyridine] moiety) via amine-aldehyde condensation. We show that this hybrid catalyst can reduce CO2 to form CO under visible light illumination with excellent selectivity and enhanced activity with respect to its parent MOF and corresponding homogeneous counterpart. Using steady state and transient absorption (TA) spectroscopy, we show that the enhanced photocatalytic activity of UiO-68-Fe-bpy is attributed to the elongated excited state lifetime of Fe(bpy)Cl3 after being incorporated to the UiO-68-NH2 platform. This work demonstrates the great potential of MOFs as a next generation platform for solar fuel conversion.Solvent responsive magnets comprise a class of molecule-based materials where lattice solvent driven structural transformation leads to the switching of magnetic properties. Herein, we present a special type of magnet where single-crystal to single-crystal (SCSC) transformations within mononuclear DyIII compounds result in the switching of DyIII single-molecule magnets (SMMs). This structural transformation involves lattice solvents which leads to significant changes in the color and magnetic properties. Additionally, the relaxation dynamics of mononuclear DyIII compounds are perceptibly fine-tuned by the modification of β-diketonate ligands. The uniaxial magnetic anisotropies, magneto-structural correlations and the relaxation mechanism were investigated by magnetic studies and ab initio calculations. These experimental and theoretical studies indicate that compound 2 exhibits the best magnetic properties in compounds 1-4. The experimental observation is supported by the theoretical prediction of QTM time (τZeeQTM) as theτZeeQTM of 2 is remarkably longer than those of the other three compounds by an order of magnitude. This means that, compared with 1, 3, and 4, the magnetic relaxation of 2 is significantly slower. Meanwhile, 2 has the largest value of axial ESP (the axial electrostatic potential), which supports the smallest gXY value in these compounds, resulting in better SMM properties. The present results offer a systematic synthesis regulation to change the magnetization dynamics and further understand magneto-structural correlations for DyIII SMMs.We studied the structure of brushes consisting of branched oligolactide (OLA) chains grafted onto the surface of cellulose nanoparticles (CNPs) in polylactide (PLA) and compared the outcomes to the case of grafting linear OLA chains using atomistic molecular dynamics simulations. The systems were considered in a melt state. The branched model OLA chains comprised one branching point and three branches, while the linear OLA chains examined had a molecular weight similar to the branched chains. It was shown that free branches of the branched OLA chains tend to fold back toward the CNPs due to dipole-dipole interactions within the grafted layer, in contrast to the well-established behavior of the grafted uncharged branched chains. This result, however, is in qualitative agreement with the conformational behavior known for linear OLA chains. At the same time, no significant difference in the effectiveness of covering the filler surface with grafted branched or linear OLA chains was found. In terms of the expelling ability of the grafted chains and the interaction between PLA and CNP or OLA, the linear chains were broadly similar (sparse grafting) or better (intermediate or dense grafting) compared to the branched ones. Thus, the grafted lactide chains with a linear architecture, rather than their branched counterpart, may be preferable for the covalent modification of cellulose nanoparticles.A density functional theory study has been performed to investigate cation-doped Sn2O4 clusters for selective catalytic reduction of CO2. We study the influence of Si and Ti dopants on the height of the H2 dissociation barrier for the doped systems, and then the subsequent mechanism for the conversion of CO2 into formic acid (FA) via a hydride pinning pathway. The lowest barrier height for H2 dissociation is observed across the 'Ti-O' bond of the Ti-doped Sn2O4 cluster, with a negatively charged hydride (Ti-H) formed during the heterolytic H2 dissociation, bringing selectivity towards the desired FA product. The formation of a formate intermediate is identified as the rate-determining step (RDS) for the whole pathway, but the barrier height is substantially reduced for the Ti-doped system when compared to the same steps on the undoped Sn2O4 cluster. The free energy of formate formation in the RDS is calculated to be negative, which reveals that the hydride transfer would occur spontaneously. Overall, our results show that the small-sized Ti-doped Sn2O4 clusters exhibit better catalytic activity than undoped clusters in the important process of reducing CO2 to FA when proceeding via the hydride pinning pathway.Our 1. Prologue section applauds some previous celebrations of Peter's inspiring ebullient adventures, including a remarkable new book by Giorgio Benedek and Peter on investigations of surfaces by helium beam scattering. The next sections treat 2. Peter's personal genealogy and 3. Peter's scientific genealogy. Section 4 presents Meanderings and serendipity on the way from Bonn to Göttingen. Section 5 lists Peter's awards and Section 6 is our Epilogue that features an Ode to Peter as well as his response.Nucleophilic phosphine catalysis is a practical and powerful tool for the synthesis of various heterocyclic compounds with the advantages of environmentally friendly, metal-free, and mild reaction conditions. The present report summarizes the construction of four to eight-membered heterocyclic compounds containing nitrogen, oxygen and sulphur atoms through phosphine-catalyzed intramolecular annulations and intermolecular [2+2], [3+2], [4+1], [3+1+1], [5+1], [4+2], [2+2+2], [3+3], [4+3] and [3+2+3] annulations of electron-deficient alkenes, allenes, alkynes and Morita-Baylis-Hillman carbonates.