Tin Tert-butoxide Research Articles

Tin asymmetric membranes for high capacity sodium ion battery anodes

Sodium-ion batteries have attracted tremendous research attention as promising candidates for next generation energy storage systems due to low-cost and high abundancy. However, comparing to current Li-ion battery technology, limitations on the anode side seriously hinder the cell performance since sodium does not easily intercalate into graphite materials. Here, tin nanoparticles embedded in various asymmetric membrane structures were developed to leverage the high capacity of tin (847 mA h g−1 based on Na15Sn4) and accommodate the significant volume expansion for long cycle life. It was demonstrated 762 mA h g−1 reversible capacity at 50 mA g−1 and stable cycling performance over 100 cycles with 92.1% capacity retention at 100 mA g−1 can be achieved for the tin asymmetric membrane electrode synthesized using polysulfone and tin tert-butoxide precursor.

Synthesis of poly(styrene oxide) with different molecular weights using tin catalysts

The polymerization reactions of styrene oxide (SO) at different temperatures for different time intervals were performed by four different tin catalysts, tin(IV) perfluorooctanoate (PFO-Sn), tin(IV) methacrylate (MAc-Sn), tin(II) chloride (SnCl2), and SnCl2/hexamethyldisilazane. Tin(IV) perfluorooctanoate and methacrylate compounds have been prepared from perfluorooctanoic acid, methacrylic acid, and tin tert-butoxide in tert-butanol. The Sn-PFO and Sn-MAc compounds were characterized by 1H, 13C NMR, FTIR, and elemental analysis. These four compounds were tested as catalysts in polymerization of SO and were effective. Polystyrene oxide (PSO) was characterized by 1H, 13C NMR, and gel permeation chromatography. High molecular weight of PSO (~138,000 Da) was recorded for the first time by this study.

Ring-opening polymerization of isopropylglycidyl ether (IPGE) with new catalysts of Ti, Sn, Al-alkoxides and comparison of its reactivity

The polymerization reactions of isopropylglycidyl ether (IPGE) were carried out by various catalysts potassium hydroxide, potassium tert-butoxide, tetrafluorophthalate aluminum sec-butoxide, tetrafluorophthalate tin tert-butoxide, and tetrafluorophthalate–titanium isopropoxide complexes. Tetrafluorophthalate–aluminum, tin, and titanium have been prepared from aluminum sec-butoxide, tin tert-butoxide, and titanium isopropoxide in alcohol and tetrafluorophthalic acid. Poly-IPGE and catalysts were characterized by 1H, 13C NMR, FTIR spectroscopy, elemental analysis, and gel permeation chromatography. IPGE is less reactive toward OH− nucleophiles than 3-glycidyloxypropyltrimethoxysilane and propylene oxide.

Optimal synthesis parameters and application of Sn-MCM-41 as an efficient heterogeneous catalyst in solvent-free Mukaiyama-type aldol condensation

Hydrothermal synthesis of mesoporous Sn-MCM-41 materials was established by optimizing crucial synthesis parameters. Several synthesis compositional variables such as molar TMAOH/SiO 2, CTMABr/SiO 2, H 2O/SiO 2 and SiO 2/SnO 2 ratios in the starting gel, type of silica and/or tin sources and synthesis time whose cause and effect relationship on the properties of Sn-MCM-41 materials have been explored. Gels with molar compositions SiO 2: w Sn O 2 : xCTMABr: yTMAOH: zH 2O where 0.00 < w < 0.01, 0.18 < x < 0.32, 0.25 < y < 0.35, 25 < z < 45 were prepared and subjected for hydrothermal treatment at 383 K. Under identical and judiciously pre-optimized synthesis conditions, the influence of different combinations of silicon sources and tin sources on structural properties, tin configuration and morphology of Sn-MCM-41 has been investigated. Powder XRD, DRUV-vis, AAS, SEM and low temperature N 2 adsorption/desorption isotherms have been employed to characterize the products. Selected Sn-MCM-41 materials prepared using different silica and tin sources were evaluated for their efficiency in Mukaiyama-aldol condensation of methyl trimethylsilyldimethyl ketene acetal and benzaldehyde under solvent-free system. Invariably, the β-hydroxy ester selectivity was found to be 100% irrespective of the conversion levels. Among different source combinations, Sn-MCM-41 prepared with: (1) fumed silica and tin tetrachloride and (2) fumed silica and tin tert-butoxide have shown higher catalytic activity. The differences in the catalytic behavior of the materials were found to depend on tin content, the intrinsic differences in Sn siting and textural properties. Sn-MCM-41 materials have shown noticeable morphological differences upon changing the silica sources.

Nonaqueous Synthesis of Uniform Indium Tin Oxide Nanocrystals and Their Electrical Conductivity in Dependence of the Tin Oxide Concentration

Indium tin oxide nanoparticles with tin oxide contents varying from 2 to 30 wt % have been synthesized via a nonaqueous sol−gel procedure involving the solvothermal treatment of indium acetylacetonate and tin tert-butoxide in benzyl alcohol. According to powder X-ray diffraction analysis combined with Rietveld refinement all the materials are crystalline with the cubic bixbyite structure of indium oxide without any indication of SnO2 as an additional phase. Transmission electron microscopy studies proved that the nearly spherical particles are relatively uniform in size and shape with crystallite sizes in the range of 5−10 nm. X-ray photoelectron spectroscopy results showed that the final composition of the nanoparticles coincided well with the initial indium acetylacetonate-to-tin tert-butoxide ratio. Furthermore, a high amount of oxygen vacancies was detected, which contribute to the good electrical conductivity of the nanoparticles. Conductivity measurements on the as-synthesized nanopowders pressed into pellets showed a maximum conductivity of 2.56 S/cm at a dopant concentration of 15 wt % and can be further increased to 52.6 S/cm upon annealing under a nitrogen atmosphere.

Deposition and characterization of zirconium tin titanate thin films as a potential high- k material for electronic devices

There is considerable need for study of new high dielectric constant ( k) materials to replace SiO 2 in the manufacture of future CMOS logic and storage devices. Current work has focused primarily on binary metal oxides and silicates. In this work, thin films of zirconium tin titanate (ZTT) were deposited by chemical vapor deposition (CVD) using a precursor solution of zirconium tert-butoxide, tin tert-butoxide, and titanium tert-butoxide. The precursor was delivered to a reactor using direct liquid injection. The precursor is mixed such that the relative ratio of the components in the solution is at or near the desired cation ratio of the films. NMR analysis of the precursor solution and each of the individual components suggests that the components in the mixture do not interact (i.e. no ligand exchange). Compositional analysis of the films correlates to the composition of the precursor within a range of values; composition of films deposited from a given precursor composition varies with deposition temperature. The zirconium content of deposited films has been shown to decrease with increasing temperature; the titanium content increases with increasing deposition temperature, while the tin content remains relatively constant with temperature. Kinetic studies of ZTT deposition rate indicate an effective activation energy of 38.8±5 kcal/mol. Depending on processing parameters, dielectric constants of ZTT films were shown to range from 21 to 36 with no post-deposition anneal.

Electronically addressable SnO2 inverted opal gas sensors fabricated on interdigitated gold microelectrodes.

Electronically addressable thin films of tin oxide gas sensors with well-defined opaline microstructures and reproducible sensor-to-sensor responses have been fabricated on interdigitated gold microelectrodes through self-assembly growth of a monodisperse polystyrene latex film onto the electrodes followed by infiltration of tin tert-butoxide and calcination of the film.