A rich variety of inorganic-organic hybrid thioantimonates and thiostannates were prepared during the last few years under solvothermal conditions applying organic amine molecules or transition metal complexes as structure directors. In this review synthetic approaches to and structural features of these thiometallates are discussed. For thioantimonates(III) the structures range from well isolated thioanions to three-dimensional networks, whereas the structural chemistry of thiostannates(IV) is strongly dominated by the [Sn 2 S 6 ] 4− anion, and no three-dimensional thiostannate has been reported so far. In the structures of thioantimonates(III) several primary building units like the [SbS 3 ] trigonal pyramid, the [SbS 4 ] unit or even the [SbS 5 ] moiety are joined by vertex-and/or edge-linkages to form building blocks of higher structural hierarchy like [Sb 3 S 4 ] semi-cubes or Sb x S x heterocycles. A pronounced difference between thioantimonate and thiostannate chemistry is the tendency of Sb(III) to enhance the coordination geometry via so-called secondary bonds. In most cases the environment of Sb(III) is better described as a 3 + n polyhedron with n = 1 -3. The thioantimonate(V) structural chemistry is less rich than that of thioantimonates(III), and the [SbS 4 ] 3− anion shows no tendency for further condensation. By applying suitable multidentate amine molecules, transition metal cations which normally prefer bonding to the N atoms of the amines can be incorporated into the thiometallate frameworks.

Amorphous silicon is a promising high-capacity anode material for the next generation of lithium-ion batteries. However, the enormous volume expansion of the active material during lithiation up to 400% (V/V 0) is held responsible for capacity fading during cycling. In this study we measured continuously the volume modifications taking place during galvanostatic lithiation of amorphous silicon thin film electrodes by in-operando neutron reflectometry experiments. The results indicate (after initial effects) a linear increase in volume as a function of lithiation time and lithium content independent of current density and initial film thickness. The experimental results are in agreement with recent atomistic calculations.

In order to better understand the critical influence of the synthesis parameters during preparation of Cu/ZnO catalysts at the early stages of preparation, the aging process of mixed Cu,Zn hydroxide carbonate precursors was decoupled from the precipitation and studied independently under different conditions, i.e. variations in pH, temperature and additives, using in situ energy-dispersive XRD and in situ UV-Vis spectroscopy. Crystalline zincian malachite, the relevant precursor phase for industrial catalysts, was formed from the amorphous starting material in all experiments under controlled conditions by aging in solutions of similar composition to the mother liquor. The efficient incorporation of Zn into zincian malachite can be seen as the key to Cu/ZnO catalyst synthesis. Two pathways were observed: direct co-condensation of Cu(2+) and Zn(2+) into Zn-rich malachite at 5 ≥ pH ≥ 6.5, or simultaneous initial crystallization of Cu-rich malachite and a transient Zn-storage phase. This intermediate re-dissolved and allowed for enrichment of Zn into malachite at pH ≥ 7 at later stages of solid formation. The former mechanism generally yielded a higher Zn-incorporation. On the basis of these results, the effects of synthesis parameters like temperature and acidity are discussed and their effects on the final Cu/ZnO catalyst can be rationalized.

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Thioantimonate chemistry is characterized by a fascinating structural and chemical diversity. 1 One intriguing structural feature is that for a given Sb/S ratio the dimensionality of the thioantimonate anion may range from zero-dimensional (0D) isolated anions to three-dimensional (3D) networks. Analyzing the thioantimonate(III) structures containing charge compensating cations of different sizes and charges, only a moderate influence on the dimensionality could be identified. For instance, 0D Ni 2+ containing thioantimonates(III) were obtained with diethylenetriamine (dien) as solvent; one-dimensional (1D) chains with ethylenediamine (en), dien, and tris(2-aminoethyl)amine (tren); two-dimensional (2D) layers with 1,2-diaminopropane (1,2-dap), dien, and tren; and 3D networks with en, dien, and 1,4,8,11-tetraazacyclotetradecane (cyclam). This clearly demonstrates that the choice of the size/charge of the solvent/structure director has no effect on the dimensionality of the inorganic part of the compounds. There are no general rules allowing prediction of the chemical composition and/or crystal structure of thioantimonates formed under solvothermal conditions. Thiometallate compound formation was investigated by us applying in situ X-ray scattering and X-ray absorption techniques demonstrating the complexity of the reactions occurring under solvothermal conditions. 2À5 Concerning the structural chemistry of thioantimonates containing Ni-amine complexes as structure directing and charge balancing agents, two compounds are 0D, namely, [Ni (dien) 2 ]-Sb 4 S 8 6 and [Ni(dien) 2 ] 3 (Sb 3 S 6 ) 2 . 7 In the former compound, four SbS 3 moieties share common corners to form the [Sb 4 S 8 ] 4À heterocycle. 6 The [Sb 3 S 6 ] 3À anion 7 is constructed by three vertex-linked SbS 3 pyramids. Several isolated thioantimonate(V) anions could also be isolated like [Ni(en) 3 ] 3 (SbS 4 )(NO 3 ), 8 [Ni-(dien) 2 ] 3 (SbS 4 ) 2 , 9 (paH)[Ni(tren)SbS 4 ], 10 [Ni(chxn) 3 ] 3 (SbS 4 ) 2 3 4H 2 O 11 and [Ni(en) 3 (enH)]SbS 4 . 12 Only in (paH)[Ni(tren)-SbS 4 ] 10 the Ni 2+ ion is octahedrally surrounded by four N atoms of the amine and by two S atoms of the [SbS 4 ] 3À anion. 1D chain anions are found in [Ni(tren)]Sb 2 S 4 , 13 [Ni(dien) 2 ]Sb 4 S 9 , 14 [Ni(tren)Sb 4 S 7 ], 15 [Ni(en) 3 ]Sb 2 S 4 , and [Ni(en) 3 ]Sb 4 S 7 . 16 The compound [Ni(tren)]Sb 2 S 4 13 is a rare example where the Ni 2+ ion is incorporated in the thioantimonate network via NiÀS bonds. ABSTRACT: The new thioantimonates [Ni(aepa) 2 ] 3 Sb 6 S 12 (1), [Ni(aepa) 2 ] 6 -(Sb 3 S 6 ) 2 (SO 4 ) 3 3 2H 2 O (2), and [Ni(aepa) 2 ]Sb 4 S 7 (3) (aepa = C 5 H 15 N 3 = N-(aminoethyl)-1,3-propandiamine) were obtained under solvothermal conditions by slightly varying the reaction conditions. In all compounds the [Ni(aepa) 2 ] 2+ complexes were formed in situ during the chemical reactions. Compound 1 features the new unique [Sb 6 S 12 ] 6À cyclic anion composed by vertex-linked SbS 3 trigonal pyramids. This [Sb 6 S 12 ] 6À cyclic anion represents the largest isolated thioantimon...