Tin Hydroxide Research Articles

Catena-Poly[[cyclohexyldiphenyltin(IV)]-μ-hydroxido-κ2O:O

The title polymeric mixed-organyl tin hydroxide, [Sn(C6H5)2(C6H11)(OH)]n, hass a hydroxide-bridged chain structure; the tin center shows trans-C3SnO2 trigonal bipyramidal coordination. The Sn atom lies on a special position of site symmetry m; the symmetry element relates one phenyl ring to the other and also relates one half of the cyclo­hexyl ring to the other half.

Products of hydrolysis of C, N-chelated triorganotin(IV) chlorides and use of products as catalysts in transesterification reactions

Triorganotin(IV) chlorides containing one L CN chelating ligand were hydrolyzed with an excess of sodium hydroxide. The composition of the products is strongly dependent on the nature of the organic groups bound to the tin atom. Di( n-butyl)tin, dimethyltin as well as the diphenyl derivative exhibits an equilibrium between hydroxide and stannoxane forms (oxide), whereas alkyltin species react spontaneously and reversibly with carbon dioxide present in the air to form carbonate species. On the other hand, diphenyl derivatives display virtually no reaction with CO 2 towards carbonates, while the di- t-butyl-substituted tin derivative is stable under the same experimental condition and remains as a tin hydroxide. In the case of the dimethyltin derivative, a methyl group migration was observed with displacement of one L CN chelating ligand during the reaction on the air. The coordination geometry of the tin central atom(s) of all studied compounds can be described as trigonal bipyramidal with a dative bonded dimethylamino group occupying one coordination site. The catalytic activity of these compounds in transesterification reactions is generally lower compared to the systems reported in the literature, with the exception of the transesterification of ethyl acetate by cyclohexanol which displays a remarkable activity.

Preparation of highly dispersed antimony-doped tin oxide nanopowders by azeotropic drying with isoamyl acetate

Antimony-doped tin hydroxide colloid precipitates were prepared by hydrolysis of SnCl 4·5H 2O and SbCl 3 ethanol solutions. Isoamyl acetate was selected as azeotropic drying solvent and was compared with the most commonly used n-butanol solvent on treating precipitate for low hard agglomeration precursor powders. The FT-IR, BET, XRD. and TEM results of the precursor powders and calcinated antimony-doped tin oxide powders were recorded. The results demonstrate that isoamyl acetate is an excellent azeotropic drying solvent that can effectively prevent the agglomeration of particles and greatly improve the fluffiness of the obtained dried powders. After these precursor powders are calcined, antimony-doped tin oxide nanopowders with tetragonal rurile structure and high dispersivity can be obtained.

Preparation of Highly Dispersed Antimony-doped Tin Oxide Nano-powder via Ion-exchange Hydrolysis of SnCl4 and SbCl3 and Azeotropic Drying

Antimony-doped tin hydroxide colloid precipitates have been synthesized by hydrolysis of SnCl4 and SbCl3 using: (1) an ion-exchange hydrolysis to remove chlorine ions, and (2) isoamyl acetate as an azeotropic solvent to obviate water. The obtained dried powder is of high dispersivity without any need for further grinding. The size and dispersivity of the final particles are investigated with the aid of TG-DTA, BET, XRD and TEM. After having calcined, the antimony-doped tin oxide nanopowder possesses a tetragonal rutile structure with high dispersivity, uniform particles and low hard agglomeration.

Urea-based hydrothermal synthesis of ITO nanopowders

Nanosized tin-doped indium oxide (ITO) powders were prepared by hydrothermally treating either the coprecipitated hydroxides of tin and indium gels with the addition of a small amount of urea or the solution of indium and tin aqueous salts in presence of urea at 240°C for about two days followed by calcination at 600°C for one hour. The effect of urea in the two different processing routes on the crystal structure and morphology of the ITO nanopowders has been investigated. Weakly-aggregated nanosized ITO powders with the uniform spherical morphology were obtained by the calcination of the hydrothermally treated coprecipitated indium and tin gels with 10 wt.% urea. However, by directly using urea as an alkaline solution during the hydrothermal treatment, the obtained ITO powders exhibit a composite morphology consisting of spheres and rods. Both of the processing routes yield a two-phase mixture consisting of rhombohedral and cubic forms of ITO.

Effects of temperature on indium tin oxide particles synthesized by co-precipitation

Indium (III) and tin (IV) hydroxides (precursor) were synthesized by a co-precipitation process at the different reaction temperature in a water bath. Nanocrystalline indium tin oxide (ITO) powders with spherical and rod shapes were obtained upon calcination. The phase transformations during calcination process in Ar gas at ambient temperature −1100 °C were investigated by TG/DTA system, X-ray diffraction and transmission electron microscopy. A mixture of In(OH) 3, InOOH and Sn 3O 2(OH) 2 preferred the path of pure In(OH) 3→In 2O 3 during calcinations in Ar gas and the powders with rhombohedral and cubic structured crystalline ITO were obtained at 600 °C. The crystal parameters changed with calcination temperature. Oxygen vacancies were developed at about 400 °C determined by resistivity decrease and the color change of powders. Characterized by TEM and FESEM, the spherical and rod shapes of the particles were prepared at bath temperature of 40 and 100 °C, respectively, and remained after calcination in Ar gas. The particles’ size showed obvious shrinkage compared with the precursors. At higher bath temperature In(OH) 3 octahedral nuclei in the cubic structure cell stacks along the closest plane (1 0 0) and evolves nano-rod due to the influence of NH 4 + on the orientation of crystals.

Infrared Spectra of M(OH)1,2,4 (M: Pb, Sn) in Solid Argon.

Infrared absorptions for the matrix-isolated lead and tin hydroxides M(OH), M(OH)2 and M(OH)4 (M = Pb, Sn) were observed in laser-ablated metal atom reactions with H2O2 during condensation in excess argon. The major M(OH)2 product was also observed with H2 and O2 mixtures, which allowed the substitution of 18O2. The band assignments were confirmed by appropriate D2O2, D2, 16O18O, and 18O2 isotopic shifts. MP2 and B3LYP calculations were performed to obtain molecular structures and to reproduce the infrared spectra. The minimum energy structure found for M(OH)2 has Cs symmetry and a weak intramolecular hydrogen bond. In experiments with Sn, HD, and O2, the internal D bond is favored over the H bond for Sn(OH)(OD). The Pb(OH)4 and Sn(OH)4 molecules are calculated to have S4 symmetry and substantial covalent character.

XPS-Studies on the Formation of Passive Layers on Sn and CuSn Alloys in 0.1 M KOH

Passive layers on tin, CuSn4 and CuSn19 were prepared in 0.1 N KOH (pH 12.5) under potentiostatic control with systematic variation of the relevant parameters, such as potential and time, and examined by X-ray photoelectron spectroscopy. XPS studies of potentiostatically polarised Sn-electrodes show the linear growth of the oxide layer thickness with increasing potential. Angular resolved-XPS measurements and XPS-depth-profiles allow the development of a model of the passive layer: In the passive potential range it consists mainly of SnO2 with a small contribution of SnO. Tin hydroxide was found only on top of the layer. Sputter profiles indicate a dominating SnO2 part which increases with the potential and the passivating time. SnO was detected underneath a layer of SnO2 with a thickness constant with potential.

Formation of 3‐Sulfanylcoumarins by SnPh3OH‐Promoted Cyclization of 3‐Aryl‐2‐Sulfanylpropenoic Acids

AbstractReaction of SnPh3OH with 3‐(2‐hydroxyphenyl)sulfanylpropenoic acid [H2(o‐hpspa)] yielded [SnPh3(SC)], where SC is deprotonated 3‐sulfanylcoumarin (3‐sulfanyl‐2H‐1‐benzopyran‐2‐one, HSC), by a cyclization process. Similarly, when 3‐(2‐hydroxy‐5‐bromophenyl)‐ and 3‐(2‐hydroxy‐3,5‐dibromophenyl)‐2‐sulfanylpropenoic acids were treated with the same tin hydroxide, the cyclization resulted in [SnPh3(BrSC)] and [SnPh3(Br2SC)], where BrSC and Br2SC are the new ligands formed from the deprotonation of 3‐sulfanyl‐6‐bromocoumarin and 3‐sulfanyl‐6,8‐dibromocoumarin, respectively. The new compounds were characterized by elemental analysis, multinuclear NMR (1H, 13C and 119Sn) and vibrational spectroscopy, and mass spectrometry. Single‐crystal X‐ray structures of these complexes all showed that the tin atom is surrounded by three phenyl C atoms and the S and O atoms of the bidentate ligand in a distorted trigonal‐bipyramidal environment. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

Infrared Spectra of M(OH)1,2,4 (M = Pb, Sn) in Solid Argon

Infrared absorptions for the matrix-isolated lead and tin hydroxides M(OH), M(OH)2 and M(OH)4 (M = Pb, Sn) were observed in laser-ablated metal atom reactions with H2O2 during condensation in excess argon. The major M(OH)2 product was also observed with H2 and O2 mixtures, which allowed the substitution of 18O2. The band assignments were confirmed by appropriate D2O2, D2, 16O18O, and 18O2 isotopic shifts. MP2 and B3LYP calculations were performed to obtain molecular structures and to reproduce the infrared spectra. The minimum energy structure found for M(OH)2 has C(s) symmetry and a weak intramolecular hydrogen bond. In experiments with Sn, HD, and O2, the internal D bond is favored over the H bond for Sn(OH)(OD). The Pb(OH)4 and Sn(OH)4 molecules are calculated to have S4 symmetry and substantial covalent character.

A photoelectrochemical investigation of conversion coatings on Mg substrates

The structure, morphology and composition of conversion coatings grown in stannate bath on pure Mg were studied using potential–time, polarization curves, X-ray diffraction, scanning electron microscopy and photocurrent spectroscopy. The coating is manly constituted by crystalline magnesium–tin hydroxide, whose morphology and distribution depends on the conversion bath composition and temperature. The photoelectrochemical investigation allowed to estimate the band gap value of MgSn(OH) 6 and flat band potential. A sketch of the metal/passive film/electrolyte junction formed during conversion on the metal substrate is reported to account for the overall photoelectrochemical behaviour.

Synthesis of nanocrystalline transition metal and oxides for lithium storage

Nanosize silver and tin dioxide powders were synthesised by a novel reverse micelle technique. The reverse micelles were formed from a microemulsion of organic solvents, water based salts and surfactants. The spherical nanosize Ag powders were formed via in situ reduction. The tin hydroxide precipitates were formed in reverse micelles and converted to tin dioxide nanopowders after heat treatment. The Ag and SnO 2 powders have a particle size in the range of 20–50 nm. The as-prepared nanosize Ag and SnO 2 nanopowders were used in lithium-ion cells for lithium storage.

Different reactivity of the heavier group 14 element alkyne analogues Ar′MMAr′ (M = Ge, Sn; Ar′ = C6H3-2,6(C6H3-2,6-Pri2)2) with R2NO

The reactions of the digermanium and ditin alkyne analogues Ar'MMAr' (M = Ge or Sn) with R2NO, (R2NO = Me2C(CH2)3CMe2NO or N2O), result in complete MM bond cleavage to afford the germylene :Ge(Ar')ONR2 or the germanium(II) or tin(II) hydroxides {M(Ar')(micro-OH)}2.

Further study of tris(cyclohexyl)stannane compounds, Cy 3SnX. Syntheses of the compounds with X = Br, I, N 3 and NCS and redetermination of the crystal structures of Cy 3SnX (X = Br and I)

Methods of preparation and far IR data are presented for various Cy 3SnX compounds. The synthesis of tris(cyclohexyl)tin hydroxide, Cy 3SnOH, is also described. Redeterminations of the crystal structures of tris(cyclohexyl)tin bromide and iodide, Cy 3SnBr and Cy 3SnI, confirm their molecular nature and improve considerably upon the results reported earlier [S. Calogero, P. Ganis, V. Peruzzo, G. Tagliavini, G. Valle, J. Organomet. Chem. 220 (1981) 11] providing, in both cases, lower Rfactors and, in particular, a revised estimate of the Sn–I bond length, now 2.7463(6) Å.

Preparation and property control of nano-sized indium tin oxide particle

Indium tin oxide (ITO) particles of 20–30 nm in diameter, which would be used as coating material for electromagnetic wave shield, were synthesized by co-precipitation of indium chloride and tin chloride. Size and shape of particles were controlled by pH of co-precipitation solution, thermal oxidation temperature and tin contents. The prepared particles were thermally reduced under hydrogen gas to control electrical properties. When the solution pH was 6.75, plate type of particles with 60 nm size was coexisted with spherical particles of 20 nm size and the part of crystal structure was hexagonal. As pH was increased, plate type of particles was disappeared and 20–30 nm size of spherical particles were formed. Size of ITO particles was increased and particle resistance was decreased with increasing thermal oxidation temperature of indium tin hydroxide in the range of 400–700 °C. Particle size was decreased as tin content was increased from 3.18 to 21.11 at.% Sn/In in co-precipitation. The resistance of particles had a minimum point with changing of tin contents. The lowest resistance was shown in the region of about 3–5 at.% Sn in ITO. It was confirmed by Auger electron spectroscopy (AES) that tin ratio of ITO particle was increased with increasing tin contents.

Preparation and property control of nano-sized indium tin oxide particle

Indium tin oxide (ITO) particles of 20–30 nm in diameter, which would be used as coating material for electromagnetic wave shield, were synthesized by co-precipitation of indium chloride and tin chloride. Size and shape of particles were controlled by pH of co-precipitation solution, thermal oxidation temperature and tin contents. The prepared particles were thermally reduced under hydrogen gas to control electrical properties. When the solution pH was 6.75, plate type of particles with 60 nm size was coexisted with spherical particles of 20 nm size and the part of crystal structure was hexagonal. As pH was increased, plate type of particles was disappeared and 20–30 nm size of spherical particles were formed. Size of ITO particles was increased and particle resistance was decreased with increasing thermal oxidation temperature of indium tin hydroxide in the range of 400–700 °C. Particle size was decreased as tin content was increased from 3.18 to 21.11 at.% Sn/In in co-precipitation. The resistance of particles had a minimum point with changing of tin contents. The lowest resistance was shown in the region of about 3–5 at.% Sn in ITO. It was confirmed by Auger electron spectroscopy (AES) that tin ratio of ITO particle was increased with increasing tin contents.

Thermodynamic Calculation of Nucleation during Codeposition of Indium and Tin Hydroxides

A thermodynamic calculation of nucleation during codeposition of indium and tin hydroxides is presented. A thermodynamic probability of phase formation is evaluated. The theoretical results obtained are in good agreement with experiment.

Atomic scale flattening of organosilane self-assembled monolayer and patterned tin hydroxide thin films

We have succeeded in fabricating an atomic flattening surface of organosilane self-assembled monolayers (SAMs) on a Si substrate. In the present process, the octadecyltrichlorosilane (OTS) compound was selected as the starting material for the SAM. The OTS–SAM was formed by the reaction between the OTS molecules and the substrates, which were hydrogen terminated Si(001) (H:Si) and silica covered on Si(001) (SiO 2/Si), at room temperature in a N 2 atmosphere. The formation rate of the OTS–SAM onto H:Si was smaller than that on SiO 2/Si. Interestingly, the hydrophobicity of the OTS–SAM was observed to increase the amount formed on H:Si in comparison with that on SiO 2/Si. The photo reactivity of the SAMs formed on each substrate was also investigated by using ultraviolet (UV) irradiation in ambient air. Tin hydroxide thin films were site-selectively deposited on the patterned OTS–SAM/Si substrate in order to clarify the cleavage of the OTS–SAM by the UV irradiation.

The underpotential deposition of Sn on Pt in acid media. Cyclic voltammetric and electrochemical quartz crystal microbalance studies

This work describes the studies of tin underpotential deposition on Pt electrodes in acid media by using cyclic voltammetry and electrochemical quartz crystal microbalance techniques. The voltammetric results were analyzed and it was verified the same values of anodic charge densities for the Sn in the solutions of perchloric acid with tin sulfate or chloride. The charge density value found (380 μC cm −2), in the potential region from 0.4 to 0.8 V, was attributed to the oxidation of Sn to Sn 4+ (0.9 monolayer). The electrochemical quartz crystal microbalance results showed a mass–charge ratio of 16 g mol −1 (43 ng cm −2) and 8 g mol −1 (50 ng cm −2) in the same potential region for tin oxidation in different electrolyte solutions. These relationships are due to the formation of Sn(OH) 4 and SnO 2, respectively. The differences observed in relation to the formation of Sn(OH) 4 in solutions containing SnSO 4 and SnCl 2 were due to the presence of HSO 4 − in these solutions. In this manner the OH - can adsorb on Sn in perchloric acid media with SnSO 4. The tin hydroxide and oxide are reduced in the scanning to the potentials between 1.55 and 0.05 V.

Temporal sensitivity ofAlternaria solani to foliar fungicides

Alternaria solani Sorauer (Ellis) is a causal agent of early blight of potato (Solanum tuberosum L.). Sensitivity to chlorothalonil, triphenyl tin hydroxide (TPTH), and mancozeb was determined for field isolatesof A. solani in 1998 and 1999. Specifically, the relative sensitivity ofA. solani to foliar fungicides in field populations collected from several commercial fields was evaluated over the course of two growing seasons. Sensitivity to these foliar fungicides was determined with anin vitro spore-germination assay method. The fungicide concentration that inhibited conidial germination by 50% (EC50) was estimated for each isolate. Sensitivity ofA. solani isolates to TPTH and mancozeb varied little during the growing season, possibly because there were few TPTH and mancozeb applications made to the fields studied. At several locations, however, repeated exposure ofA. solani populations to chlorothalonil resulted in considerable variability in sensitivity, frequently causing isolates to have decreased sensitivity to this fungicide at the end of the growing season. In five of seven fields, isolates of A.solani collected at the end of the season were significantly less sensitive to chlorothalonil than isolates collected at the beginning of the season.