Impact on Anode Performance of Lithium-ion Batteries by Deep Cryogenic Treated SnSb/C Nanofiber Derived from Inorganic Precursors

The major obstacle prohibiting the practical application of Sn-based anodes is drastic volume variation during cycling processes. Here, polyacrylonitrile (PAN) was acted as carbon source, stannic chloride pentahydrate (SnCl4.5H2O) and antimony chloride (SbCl3) were used as SnSb precursors. SnSb/C nanofibers were prepared via simple electrospinning, deep cryogenic treatment, and carbonization, its applied in anode materials for Lithium ion Batteries (LIBs) to achieve excellent cycle performance(115.5% capacity retention for 100 cycles). The improvement of electrochemical performance is mainly attributed to the synergistic effect of deep cryogenic treated special SnSb/C nanofibers precursor. In the deep cryogenic treatment process, the crystalline water in the precursor has a pore forming effect, the porous nanofiber structure leads to the phenomenon of capacity increase. The above results indicate that comprehensive consideration of deep cryogenic treatment and nanofiber precursors is a new idea to enhance the electrochemical performance of LIBs anode materials.

Catalytic Conversion of α-Pinene to High-Density Fuel Candidates Over Stannic Chloride Molten Salt Hydrates

The synthesis of dimeric products from monoterpene hydrocarbons has been studied for the development of renewable high-density fuel. In this regard, the conversion of α-pinene in turpentine over stannic chloride molten salt hydrates (SnCl4·5H2O) as a catalyst was investigated, and the reaction products were analyzed with gas chromatography/flame ionization detector/mass spectrometer (GC/FID/MS). Overall, the content of α-pinene in a reaction mixture decreased precipitously with an increasing reaction temperature. Almost 100% of the conversion was shown after 1 h of reaction above 90 °C. From α-pinene, dimeric products (hydrocarbons and alcohols/ethers) were mostly formed and their yield showed a steady increase of up to 61 wt% based on the reaction mixture along with the reaction temperature. This conversion was thought to be promoted by Brønsted acid activity of the catalyst, which resulted from a Lewis acid-base interaction between the stannic (Sn(IV)) center and the coordinated water ligands. As for the unexpected heteroatom-containing products, oxygen and chlorine atoms were originated from the coordinated water and chloride ligands of the catalyst. Based on the results, we constructed not only a plausible catalytic cycle of SnCl4·5H2O but also the mechanism of catalyst decomposition.

Fabrication of Hollow and Porous Tin-Doped Indium Oxide Nanofibers and Microtubes via a Gas Jet Fiber Spinning Process

We report the morphologies of tin-doped indium oxide (ITO) hollow microtubes and porous nanofibers produced from precursor solutions of polyvinylpyrrolidone (PVP), indium chloride (InCl3), and stannic chloride (SnCl4). The polymer precursor fibers are produced via a facile gas jet fiber (GJF) spinning process and subsequently calcined to produce ITO materials. The morphology shows strong dependence on heating rate in calcination step. Solid porous ITO nanofibers result from slow heating rates while hollow tubular ITO microfibers with porous shells are produced at high heating rates when calcined at a peak temperature of 700 °C. The mechanisms of formation of different morphological forms are proposed. The ITO fibers are characterized using several microscopy tools and thermogravimetric analysis. The concentration of inorganic salts in precursor solution is identified as a key factor in determining the porosity of the shell in hollow fibers. The data presented in this paper show that GJF method may be suitable for fabrication of hollow and multi-tubular metal oxide nanofibers from other inorganic precursor materials.

Photodegradation of Gas Phase Benzene by SnO2 Nanoparticles by Direct Hole Oxidation Mechanism

Photodegradation of gas phase benzene by SnO2 nanoparticles has been studied in humid air, dry air and N2 by using a tubular photoreactor. The SnO2 nanoparticles are synthesized by the oxidation of anhydrous stannic chloride (SnCl4) in a propane/air turbulent flame. Direct hole oxidation and the ·OH radical mechanisms have been discussed based on experimental results. The goal of this research is to explore a viable and efficient alternative photocatalyst and photocatalytic process, in particular, for humidity-tolerant photocatalyst or photocatalytic process in environmental applications.

A facile method for synthesis of SnS2 with different morphologies by an ambient pressure tetraethylene glycol solution process

An ambient pressure solution chemical process was used for synthesis of SnS2 nanocrystals with different morphologies such as nanoparticles, nanosheets, nanospheres and so on. The process was conducted by using diethylene glycol as solvent, stannic chloride and thioacetamide as precursors, polyvinylpyrrolidone as capping agent. The influence of synthesized temperature and reducing agent on the morphologies and phases of product were investigated based on XRD, TEM, HRTEM and EDX. Optical properties of SnS2 nanocrystals were characterized. The results showed that pure phase, ultrathin SnS2 nanosheets were prepared with few polyvinylpyrrolidone exited.

UTILIZATION OF INDONESIAN LOCAL STANNIC CHLORIDE (SnCl4) PRECURSOR IN THE PROCESS OF MAKING FLUORINE- DOPED TIN OXIDE (FTO) CONDUCTIVE GLASS

UTILIZATION OF INDONESIAN LOCAL STANNIC CHLORIDE (SnCl4) PRECURSOR IN THE PROCESS OF MAKING FLUORINE-DOPED TIN OXIDE (FTO) CONDUCTIVE GLASS. Thin layer of fluorine- doped tin oxide (FTO) conductive glass has been deposited on a glass substrate heated at a temperature of 350°C using the ultrasonic spray pyrolysis nebulizer method with variations in fluorine doping and substrate temperatures. This experiment uses the raw material of Indonesian local stannic chloride (SnCl4) (PT Timah Industri) as a precursor with a temperature variation of 250, 300, 350, 400°C. The structure and morphology of the optical and electrical properties of all the thin layers have been examined. XRD results show that all thin layers have a tetragonal crystal structure. In this experiment, there is a significant influence on the role of fluorine doping on resistivity and transmittance values. With the addition of 2% wt doping, the resistivity and transmittance values decrease. The optimum value is obtained by doping 2 wt%, substrate temperature of 350°C with a resistivity value of 9.28.10-5 Ω.cm and transmittance value of 88%.