Chemical compounds with an element in more than one oxidation state have been labelled as "mixed-valence" systems. The contribution about detailed examination of green AgI2AgII(SbF6)4 compound written by leading authors Z. Mazej (JSI) and W. Grochala (Univesity in Warsaw) together with co-workers (T. Michałowski and J. Szydłowska, University in Warsaw; E. Goreshnik, JSI; Z. Jagličić, University in Ljubljana; I. Arčon, JSI, University of Nova Gorica) has been reported in Dalton Transactions. It's a first example of a of Ag compound with random distribution of Ag(I) and Ag(II) cations on the same crystallographic sites in the crystal lattice with the preserved localized-valence character. The contribution has been selected for the inside front cover of issue 24 of the Dalton Transactions.
COBISS.SI-ID: 3901947
A new class of inorganic aerogels – fluoride aerogels based on AlF3, were prepared in a novel direct solvothermal process that combines fluoride sol-gel synthesis and high temperature supercritical drying. Very voluminous bulk aerogels were obtained only in MeOH-containing solvents. Under these conditions, remarkably stable methoxy (MeO) species are formed that deactivate the surface and lead to formation of anisotropic nanoparticles in the form of nanorods. Entanglement of these particles prevents excessive shrinkage and allows the formation of very open and relatively rigid aerogel structures. Some other characteristics of the fluoride nanoparticles, like crystallinity, particle size, and uniformity, can be effectively controlled by the temperature of the solvothermal process. Developed methodology is flexible and allows a controllable preparation of regularly shaped and uniformly sized fluoride nanoparticles.
COBISS.SI-ID: 29050407
The novel composite MoS2/C material was synthesised and characterised. MoS2/C is the first single synthesis step composite, containing MoS2 inorganic fullerenes (IF) interconnected with carbon. Inorganic fullerene units with round 12 nm in diameter are interconnected by amorphous carbon inclusions and form the agglomerates 50–100 µm in size. Urchin-like MoS2 catalyst exhibited higher activity compared to commercial MoS2 powder in hydrodeoxygenation of liquified wood. Oxygen content decreased from 43.3 % to 8.2 % (wt.) while residual phenolic oxygen is not removable with this particular catalyst. Observed catalytic performance offer new solutions in terms of biofuel processing. The research work was done in cooperation with the National Institute of Chemistry, Slovenia.
COBISS.SI-ID: 5537562
New types of [XeF5]+ salts, i.e., NO2XeF5(SbF6)2 and XeF5[Cu(SbF6)3], are derived from reactions between XeF5SbF6 and NO2SbF6 or Cu(SbF6)2, respectively. The crystal structure of the former consists of [NO2]+ and [XeF5]+ cations and [SbF6]– anions. The main feature of the crystal structure of XeF5[Cu(SbF6)3] are rings of CuF6 octahedra that share apexes with SbF6 octahedra connected into an infinite tridimensional framework. This arrangement leads to the formation of cavities within which [XeF5]+ cations are located.
COBISS.SI-ID: 28429863
Fluorinated reduced graphene oxide (F-rGO) was synthesised by a direct fluorination of reduced graphene oxide with F2 or XeF2/BF3 in anhydrous HF. Characterization performed by HAADF-STEM and solid-state NMR confirmed the formation of C–F bonds, which is also accompanied by change in the color of samples from graphite gray to light yellow. F-rGO has been used as an interlayer additive supported by a glass fiber separator in lithium–sulfur batteries in order to block the diffusion/migration of polysulfides from the porous positive electrode to the metallic lithium electrode and to prevent the redox shuttle effect. Electrochemical cycling of these Li–S batteries has confirmed the beneficial role of F-rGO separators, with a more pronounced effect observed for high degrees of fluorination. XPS studies have shown a direct effect on the amount of Li2S and polysulfides found on the lithium electrode and evidenced a better reversibility of reduction/oxidation mechanisms of sulfur at the positive electrode upon discharge/charge.
COBISS.SI-ID: 29021479