| 1. |
- Buvailo, Halyna I., et al.
(författare)
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Copper-containing hybrid compounds based on extremely rare [V2Mo6O26]6- POM as water oxidation catalysts
- 2019
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Ingår i: Inorganic Chemistry Frontiers. - : Royal Society of Chemistry (RSC). - 2052-1545 .- 2052-1553. ; 6:7, s. 1813-1823
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Tidskriftsartikel (refereegranskat)abstract
- Herein, we report two approaches to the synthesis of heterometallic complexes (NH4)(2n)(H(2)en)(n){[Cu(en)(2)][alpha-V2Mo6O26]}center dot 4nH(2)O (1), (NH4)(2){[Cu(dien)(H2O)](2)[alpha-V2Mo6O26]}center dot 5H(2)O (2) and (NH4)(2){[Cu(dien)(H2O)](2)[alpha-V2Mo6O26]}center dot 8H(2)O (3) that have been employed in homogeneous photochemical oxidation of water to dioxygen. In these hybrid metalorganic-inorganic compounds, copper-containing complex fragments are covalently bound to the rare vanadium-disubstituted alpha-octamolybdate cluster. They exhibit variable catalytic activity controlled by the local coordination environment of copper reaching a notably high turnover frequency of 0.24 s(-1) for 3 in combination with a relatively low water oxidation overpotential. The complexes have been also used as precursors for the preparation of mixed oxide phases that have proven to be active heterogeneous water oxidation catalysts.
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| 2. |
- Gerber, Evgeny, et al.
(författare)
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Insight into the structure-property relationship of UO2 nanoparticles
- 2021
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Ingår i: Inorganic Chemistry Frontiers. - : Royal Society of Chemistry (RSC). - 2052-1545 .- 2052-1553. ; 8:4, s. 1102-1110
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Tidskriftsartikel (refereegranskat)abstract
- Highly crystalline UO2 nanoparticles (NPs) with sizes of 2–3 nm were produced by fast chemical deposition of uranium(IV) under reducing conditions at pH 8–11. The particles were then characterized by microscopy and spectroscopy techniques including high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), high-energy resolution fluorescence detection (HERFD) X-ray absorption spectroscopy at the U M4 edge and extended X-ray absorption fine structure (EXAFS) spectroscopy at the U L3 edge. The results of this investigation show that despite U(IV) being the dominant oxidation state of the freshly prepared UO2 NPs, they oxidize to U4O9 with time and under the X-ray beam, indicating the high reactivity of U(IV) under these conditions. Moreover, it was found that the oxidation process of NPs is accompanied by their growth in size to 6 nm. We highlight here the major differences and similarities of the UO2 NP properties to PuO2, ThO2 and CeO2 NPs.
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| 3. |
- Gorelova, Liudmila, et al.
(författare)
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Edge-sharing BO4 tetrahedra and penta-coordinated silicon in the high-pressure modification of NaBSi3O8
- 2022
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Ingår i: Inorganic Chemistry Frontiers. - : ROYAL SOC CHEMISTRY. - 2052-1545 .- 2052-1553. ; 9:8, s. 1735-1742
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Tidskriftsartikel (refereegranskat)abstract
- The high-pressure behavior of the borosilicate reedmergnerite NaBSi3O8 has been studied using in situ single-crystal X-ray diffraction and Raman spectroscopy up to 35 GPa. The crystal structure of NaBSi3O8 contracts homogeneously upon compression up to 12 GPa, while at higher pressures it undergoes two phase transitions. Above 16 GPa the unit-cell volume is doubled, whereas the coordination numbers of all cations and the structural topology are preserved. Above 25 GPa the crystal structure of NaBSi3O8 contains extremely rare dimers of edge-sharing BO4 tetrahedra and earlier unknown Si2O5 groups consisting of edge-sharing SiO5 square pyramids. The structural model was corroborated by DFT calculations. This HP modification results in the first example of a borosilicate compound with edge-sharing BO4 tetrahedra.
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| 4. |
- Guo, Peng, et al.
(författare)
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Accurate structure determination of a borosilicate zeolite EMM-26 with two-dimensional 10 x 10 ring channels using rotation electron diffraction
- 2016
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Ingår i: Inorganic Chemistry Frontiers. - : Royal Society of Chemistry (RSC). - 2052-1545 .- 2052-1553. ; 3:11, s. 1444-1448
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Tidskriftsartikel (refereegranskat)abstract
- A new borosilicate zeolite vertical bar N2H36C16 vertical bar[Si22B2O48].H2O, denoted as EMM-26, has been synthesized by employing a linear dicationic organic structure directing agent 1,6-bis(N-methylpyrrolidinium) hexane (OSDA). EMM-26 has a novel zeolite framework and contains two-dimensional (2D) intersecting 10 x 10-ring channels. Its structure was solved from sub-micrometer sized crystals using rotation electron diffraction (RED) and refined against both the RED and synchrotron powder diffraction data. We have shown for the first time that RED data alone can be used to accurately determine zeolite structures. The OSDAs can be removed from the framework generating permanent pores. EMM-26 shows good CO2 uptake and CO2/CH4 selectivity.
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| 5. |
- Huang, Shiliang, et al.
(författare)
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SU-79 : a novel germanate with 3D 10-and 11-ring channels templated by a square-planar nickel complex
- 2014
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Ingår i: Inorganic Chemistry Frontiers. - : Royal Society of Chemistry (RSC). - 2052-1545 .- 2052-1553. ; 1:3, s. 278-283
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Tidskriftsartikel (refereegranskat)abstract
- An open-framework germanate denoted as SU-79 with the chemical formula [Ge12.5O26(OH)(2)]-[Ni(C3N2H10)(2)](1.1)(NH4)(0.8)(C3N2H12)(0.5)(C3N2H10)(1.5)(H2O)(2) has been synthesized under hydro/solvothermal conditions using [Ni(1,2-pda)(2)](2+) (1,2-pda = 1,2-diaminopropane) and 1,2-pda as templates. Owing to the complicated pseudo-merohedral twinning in the crystals, the rotation electron diffraction (RED) method was used for the unit cell and space group determination. The structure of SU-79 was solved and refined based on synchrotron single crystal X-ray diffraction data. SU-79 exhibits a 3D open germanate framework built with Ge-13 clusters, consisting of a 3D channel system with interconnected 10- and 11-ring channels. Interestingly, helical GeO4 tetrahedral chains with left-handed/right-handed chirality were found in the structure. The [Ni(1,2-pda)(2)](2+) complexes, adopting in a square-planar geometry, show a structure directing role on the SU-79 framework via hydrogen bonds. Comparing with its related structure, SU-67, the formation of the pseudo-merohedric twinning in SU-79 was also discussed.
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| 6. |
- Kessler, Vadim
(författare)
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A family of [Ni-8] cages templated by mu(6)-peroxide from dioxygen activation
- 2014
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Ingår i: Inorganic Chemistry Frontiers. - : Royal Society of Chemistry (RSC). - 2052-1545 .- 2052-1553. ; 1, s. 487-494
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Tidskriftsartikel (refereegranskat)abstract
- A family of exceptionally thermally stable [Ni-8] cages is reported, each being templated by a rare eta(3):eta(3):mu(6)-O-2(2-) species produced by dioxygen activation, where the reducing agent for the O-2 reduction appears to be the ligand used in the reaction mixtures, which was found within the nickel cages in its oxidized form.
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| 7. |
- Wan, Wei, et al.
(författare)
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Transmission electron microscopy as an important tool for characterization of zeolite structures
- 2018
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Ingår i: Inorganic Chemistry Frontiers. - : Royal Society of Chemistry (RSC). - 2052-1545 .- 2052-1553. ; 5:11, s. 2836-2855
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Tidskriftsartikel (refereegranskat)abstract
- Transmission electron microscopy (TEM) is an important tool for structure characterization of zeolite materials. Structural information can be obtained by different TEM techniques, for example electron diffraction (ED), high-resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM) and electron tomography (ET), each with its own advantages and limitations. These techniques are briefly introduced. Examples are given to show how these techniques can be used to solve various structure-related problems in zeolites. With this review we will describe the basic principles of transmission electron microscopy techniques for structural characterization, including recent methodological advancements. Advantages as well as challenges of using TEM for structural characterization will be described in relation to other methods. Examples of structural characterization of zeolites will be given for each of the methods.
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| 8. |
- Wang, Yilin, et al.
(författare)
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Interrupted silicogermanate with 10-ring channels : synthesis and structure determination by combining rotation electron diffraction and powder X-ray diffraction
- 2017
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Ingår i: Inorganic Chemistry Frontiers. - 2052-1545 .- 2052-1553. ; 4:10, s. 1654-1659
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Tidskriftsartikel (refereegranskat)abstract
- Silicogermanate (JU110) with an interrupted open-framework has been synthesized by using a hydrothermal method using 1,1′-(1,4-phenylenebis(methylene))bis(1-methylpyrrolidin-1-ium) hydroxide as an organic structure-directing agent (OSDA). Silicon and fluoride anions were introduced to the concentrated-gel synthesis system, and different synthetic parameters influencing the synthesis were discussed. The structure of JU110 was characterised by using rotation electron diffraction (RED) and high-resolution powder X-ray diffraction. JU110 crystallizes in the space group Fm2m (No. 42) with a = 13.9117(2) Å, b = 18.2980(3) Å and c = 32.7800(6) Å. The structure is constructed by the sti layers found in the STI framework that are pillared by D4R/Ge7 units to form a large cavity, showing 10-ring openings along [100] and 9-ring openings along [110]. Thermal stability studies showed that the framework was maintained with the loss of water molecules, but collapsed with the removal of charge-compensating cations.
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| 9. |
- Wells, Jordann A. L., et al.
(författare)
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Core and double bond functionalisation of cyclopentadithiophene-phosphaalkenes
- 2020
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Ingår i: Inorganic Chemistry Frontiers. - : Royal Society of Chemistry (RSC). - 2052-1545 .- 2052-1553. ; 7:21, s. 4052-4061
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Tidskriftsartikel (refereegranskat)abstract
- The heterofulvenoid cyclopentadithiophene-phosphaalkene is a versatile building block for opto-electronic tuning with donor and acceptor moieties. Both the annulated thienyl rings and the phosphaalkene bond can be functionalised using a variety of chemical transformations, e.g. forming C-C, C-E (E=Si, Br) bonds, or oxidation and metal coordination, respectively. Solid-state structures, optical and electronic properties are probed theoretically and experimentally, illustrating the opto-electronic tailoring opportunities at this motif.
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| 10. |
- Benazzi, Elisabetta, et al.
(författare)
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Acid-triggering of light-induced charge-separation in hybrid organic/inorganic molecular photoactive dyads for harnessing solar energy
- 2021
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Ingår i: Inorganic Chemistry Frontiers. - : Royal Society of Chemistry (RSC). - 2052-1553. ; 8:6, s. 1610-1618
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Tidskriftsartikel (refereegranskat)abstract
- H+ modulated charge-transfer in photoexcited covalent polyoxometalate-bodipy conjugates is described. The hybrid organic/inorganic molecular photoactive dyads are based on Keggin-type polyoxometalates (POMs, where KM = [PM11O39] and M = Mo or W) covalently grafted via an organotin linker to a bodipy (BOD) photosensitizer. The relative potentials of the photosensitizer and POM are aligned such that light-induced electron transfer from BOD to POM is permitted for the polyoxomolybdate KMoSn[BOD] but not effective for the polyoxotungstate analogue KWSn[BOD]. In both cases, the addition of acid shifts the redox potential of the POM only, to increase the driving force for electron transfer. This leads to charge-separation being switched on for KWSn[BOD] in the presence of acid. The addition of acid to KMoSn[BOD] accelerates charge-separation by an order of magnitude (from 2 ns to 200 ps) and is accompanied by a deceleration of charge recombination, leading to a charge-separated state lifetime of up to 1.3 μs. This behaviour is consistent with proton coupled electron transfer, which has previously been observed electrochemically for POMs, but this study shows, for the first time, the impact of protonation on photoinduced electron transfer. This journal is
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