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Liquid Nickel Salts: Synthesis,Crystal Structure Determination,and Electrochemical Synthesis of Nickel Nanoparticles
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Jeroen Sniekers Ken Verguts Dr. Neil R. Brooks Dr. Stijn Schaltin Dr. Thanh Hai Phan Dr. Thi Mien Trung Huynh Prof. Luc Van Meervelt Prof. Steven De Feyter Prof. Jin Won Seo Prof. Jan Fransaer Prof. Koen Binnemans 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):1010-1020
New nickel‐containing ionic liquids were synthesized, characterized and their electrochemistry was investigated. In addition, a mechanism for the electrochemical synthesis of nanoparticles from these compounds is proposed. In these so‐called liquid metal salts, the nickel(II) cation is octahedrally coordinated by six N‐alkylimidazole ligands. The different counter anions that were used are bis(trifluoromethanesulfonyl)imide (Tf2N?), trifluoromethanesulfonate (OTf?) and methanesulfonate (OMs?). Several different N‐alkylimidazoles were considered, with the alkyl sidechain ranging in length from methyl to dodecyl. The newly synthesized liquid metal salts were characterized by CHN analysis, FTIR, DSC, TGA and viscosity measurements. An odd‐even effect was observed for the melting temperatures and viscosities of the ionic liquids, with the complexes with an even number of carbon atoms in the alkyl chain of the imidazole having a higher melting temperature and a lower viscosity than the complexes with an odd number of carbons. The crystal structures of several of the nickel(II) complexes that are not liquid at room temperature were determined. The electrochemistry of the compounds with the lowest viscosities was investigated. The nickel(II) cation could be reduced but surprisingly no nickel deposits were obtained on the electrode. Instead, nickel nanoparticles were formed at 100 % selectivity, as confirmed by TEM. The magnetic properties of these nanoparticles were investigated by SQUID measurements. 相似文献
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Laure Laffont Laurence Maurice David Amouroux Patricia Navarro Mathilde Monperrus Jeroen E. Sonke Philippe Behra 《Analytical and bioanalytical chemistry》2013,405(9):3001-3010
We optimized a mercury (Hg) speciation extraction method for human hair in combination with species-specific isotope-dilution analysis by gas chromatography–inductively coupled plasma–mass spectrometry (GC–ICP–MS). The method was validated on human hair reference material RM (IAEA-086), which is recommended for analysis of monomethylmercury (MMHg) and inorganic mercury (IHg). Three reagents, hydrochloric acid (HCl), nitric acid (HNO3), and tetramethylammonium hydroxide (TMAH), and three extraction procedures, at ambient temperature for 12 h, microwave-assisted at 75 °C for 6 min, and oven heated at 80 °C for 2 h were tested. Extraction efficiency, recovery, and potential species transformations were evaluated for each method. The most efficient procedures, with recovery of ~90 % for each species with limited demethylation (<5 %) and methylation (0 %), were HNO3 digestion, irrespective of temperature, and microwave-assisted TMAH extraction. Acidic extraction with HCl induces significant demethylation, with production of artifacts. To correct for potential demethylation artifacts we recommend spiking with isotopically enriched standards before the extraction step. 相似文献
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Jeroen Hendrik Vrijsen Emma Van de Reydt Tanja Junkers 《Journal of polymer science. Part A, Polymer chemistry》2020,58(24):3402-3410
Thermoresponsive star polymers were synthesized by copolymerization of water-soluble acrylate monomers, di(ethylene glycol) ethyl ether acrylate (DEGA) and 2-hydroxyethyl acrylate (HEA), in a core-first approach using a modified β-cyclodextrin multifunctional initiator and photo-mediated atom transfer radical polymerization (photoATRP). The controlled character of the polymerization, as well as the formation of statistical star copolymers, was demonstrated. The lower critical solution temperature (LCST) is conveniently tuned by varying the ratio of the two hydrophilic monomers. The cyclodextrin core appears to lead to a lowering of the LCST, and introduction of a hydrophobic pocket via star block copolymer synthesis allowed for further tunability of the cloud point temperature. In the final step, we demonstrate that the star polymers made in here can be used as facile carriers and solubilizers for hydrophobic compounds, highlighting their applicability in the biomedical field. 相似文献
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