• Bulletin of the Korean Chemical Society
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• v.5 no.1
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• pp.3-16
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• 1984

The effect of solvent on the dipole moments for (chloromethyl) stannanes has been investigated by applying EHT calculation for the isomers of trigonal bipyramidal Sn(Ⅳ)$Cl_4X$ and $Cl_n$Sn(Ⅳ) $(CH_2Cl)_{4-n}$, octahedral Sn(Ⅳ)$Cl_42X$ and $Cl_nSn$(Ⅳ)$(CH_2Cl)_{4-n}$ 2X type complexes in dioxane and ethylacetate solutions (X: dioxane or ethylacetate). For Sn(Ⅳ)$Cl_4$ in dioxane solution, the calculated dipole moment for the trigonal bipyramidal Sn(Ⅳ)$Cl_4X$ type complex [isomer (b)] is closer to the experimental dipole moment than octahedral Sn(Ⅳ)$Cl_4X$2X type complexes. This calculated dipole moment suggests that Sn(Ⅳ)$Cl_4X$ may have the trigonal bipyramidal structure in dioxane solution. However, the calculated dipole moment for octahedral $Cl_3$Sn(Ⅳ) ($CH_2$Cl)2X type complex [Isomer (d)], ClSn(Ⅳ)(CH2Cl)32X type complex [Isomer(k)] and Cl2Sn(Ⅳ)(CH2Cl)22X type complex [Isomer(h)] are closer to the experimental dipole moments than other isomers for octahedral complexes and trigonal bipyramidal complexes. Such theoretical results indicate that $Cl_3Sn$(Ⅳ )($CH_2Cl$), ClSn(Ⅳ)$(CH_2Cl)_3$ and $Cl2Sn$(Ⅳ)$(CH_2Cl)_2$ complexes may have octahedral structures, Isomer(d), (k) and (h) in ethylacetate solution, respectively.

• Journal of the Korean Ceramic Society
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• v.27 no.5
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• pp.638-644
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• 1990

The C3H8 gas sensitivities of SnO2, Pd-SnO2, Pt-SnO2 gas sensor are looked over with the impregnation method of PdCl2, H2PtCl6 solution on SnO2. The Cl- ion due to incomplete decomposition of PdCl2 at 80$0^{\circ}C$ for 30 min decrease the C3H8 gas sensitivity of SnO2, and the sensitivity is increased by the impreganation of H2PtCl6 solution on SnO2 because of its lower decomposition temperature compared with PdCl2. The C3H8 gas sensitivities of Pd-SnO2, Pt-SnO2 impregnated slightly after 1st sintering are larger than that of pure SnO2 sensor because very small amount of Cl- ion exist in sample due to smaller amount of impregnaiton.

• Journal of the Korean Ceramic Society
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• v.30 no.9
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• pp.740-746
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• 1993

TiO2-SnO2 fine powders prepared by coprecipitation from TiCl4-SnCl4 aqueous solution, and their crystal structures were studied. All the TiO2-SnO2 fine powders calcined at 180~$700^{\circ}C$ showed the complete solid solution between TiO2(rutile structure) and SnO2(rutile structure). This crystal structure of TiO2-SnO2 powders is thought to be originated mainly from the heterogeneous nucleation of Ti-hydroxde on the Sn-hydroxide with coherent structure.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.3
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• pp.294-305
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• 1994

The influence of deposition parameter on the electrical, optical andsurface morphology of $SnO_2(:F)$ films prepared by ultrasonic spray deposition using DBDA and $SnCl_4.5H_2O$ as a source material was studied. Resistivity was decreased sharply with increasing F/Sn ratio in solution up to 0.6. Depending on the source material, $SnCl_4.5H_2O$ shows lower resistivity than DBDA. When F/Sn ratio in solution was 1, optical transmittance was higher DBDA than $SnCl_4.5H_2O$.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.449-453
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• 2007

Synthesis of Sn-GIC (Graphite intercalated compound) and its electrochemical characteristics were investigated to find a method for enhancing the performance of carbon anode of lithium ion battery. The content of Sn intercalated in graphite interlayer increased with increase of concentration of $SnCl_2$ solution and increase of the heat treatment temperature of dried graphite after dipped in $SnCl_2$ solution, respectively. And initial discharge capacity increased upon increase of intercalated Sn content. Sn-GIC with excellent electrochemical performance, which can be synthesized by heat treatment at $900^{\circ}C$ after dipped in 1.0 M $SnCl_2$ solution, showed 356 mAh/g of initial discharge capacity and 13% of capacity decay after 10 cycles.

• Korean Journal of Metals and Materials
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• v.48 no.10
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• pp.929-935
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• 2010

The solvent extraction behavior of Sn(IV) from hydrochloric acid was investigated using Alamine336 (Tri-n-cotylamine) as an extractant. The experimental parameters of the concentration of the HCl solution, chloride ions, extractant, and Sn(IV) were assessed. The results showed that the extraction percentage of Sn(IV) was more than 95% in our experimental range and was only slightly affected by the HCl concentration. The extraction reaction of Sn(IV) by Alamine 336 from the chloride solution was identified as follows: $SnCl_6{^{2-}}+2R_3NHCl_{(org)}=(R_3NH)_2SnCl_{6(org)}+2Cl^-$ and $K=6.3{\times}10^4$. Stripping experiments of Sn(IV) from the loaded organic phase were done by using several stripping agents. A stripping percentage of 90% was obtained with a 2.0 M NaOH solution.

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.440-444
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• 2010

$SnO_2$ powders were prepared from the calcination of stannic acids precipitated from the aqueous solution of $SnCl_4$ with ammonium nitrate as a precipitator at $90^{\circ}C$. For the comparison of properties, the stannic acids were prepared from the homogeneous precipitation method using urea as a precipitator at the same temperature. The stannic acid from ammonium nitrate at a thermal gravity analysis showed the weight loss until $700^{\circ}C$ and the percentage of total weight loss was 16.5%. The crystallization of stannic acid into $SnO_2$ finished in the calcination at $600^{\circ}C$ for 2 h. The crystallite size of $SnO_2$ increased with the increase of calcination temperature and initial concentration of $SnCl_4$ solution. In case of the same calcination condition, $SnO_2$ prepared from homogeneous precipitation using urea had a relatively smaller crystallite size rather than $SnO_2$ prepared from ammonium nitrate.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.7
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• pp.589-593
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• 2011

[ $SnO_2$ ]nano powders were prepared by solution reduction method using tin chloride($SnCl_2{\cdot}2H_2O$), hydrazine($N_2H_4$) and NaOH. The $SnO_2$ thick films for gas sensors were fabricated by screen printing method on alumina substrates and annealed at $300^{\circ}C$ in air, respectively. XRD patterns of the $SnO_2$ nano powders showed the tetragonal structure with (110) dominant orientation. The particle size of $SnO_2$ nano powders at the ratio of $SnCl_2:N_2H_4$+NaOH= 1:6 was about 60 nm. The sensing characteristics were investigated by measuring the electrical resistance of each sensor in a test box. Sensitivity of $SnO_2$ gas sensor to 5 ppm $CH_4$gas and 5 ppm $CH_3CH_2CH_3$ gas was investigated for various $SnCl_2:N_2H_4$+NaOH proportion. The highest sensitivity to $CH_4$ gas and $CH_3CH_2CH_3$ gas of $SnO_2$ sensors was observed at the $SnCl_2:N_2H_4$+NaOH= 1:8 and $SnCl_2:N_2H_4$+NaOH= 1:6, respectively. Response and recovery times of $SnO_2$ gas sensors prepared by $SnCl_2:N_2H_4$+NaOH= 1:6 was about 40 s and 30 s, respectively.

• Bulletin of the Korean Chemical Society
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• v.19 no.9
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• pp.947-951
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• 1998

$K_2NiF_4$-type layered compounds of the ($C_nH_{2n+1}NH_3)_2SnCl_4$ (n=2, 4, 6, 8, and 10) system have been synthesized from a stoichiometric mixture of $SnCl_2$ and alkyl ammonium salt using a low temperature solution technique under the inert atmosphere condition. Their crystal structures are assigned to the orthorhombic system by X-ray powder diffraction analysis. The a and b cell parameters show small changes. However, the c parameter is varied significantly according to the increment of alkyl chains of the organic layer which is located between inorganic layers in the compounds. The conformational phase transitions of the compounds are studied by the DSC in the temperature range of 300 to 500 K. FT-IR and Raman spectra are analyzed in the ranges of 1300 to 4000 cm-1 and of 50 to 360 $cm^{-1}$ with Ar-laser (λ=514.5 nm) excitation, respectively. Photoluminescence phenomena are observed for some compounds. The bond-length of Sn-Cl is determined by the EXAFS spectroscopic analysis.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.218-218
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• 2012

Nanocrystalline $SnO_2$ colloids are synthesized by hydrolysis of $SnCl_4{\cdot}5H_2O$ in aqueous ammonia solution. The synthesized $SnO_2$ nanoparticles with ca. 15 nm in diameter are coated on a fluorinedoped thin oxide (FTO) conductive substrate and heated at $550^{\circ}C$. The annealed $SnO_2$ film is treated with aqueous $TiCl_4$ solution, which is sensitzied with MK-2 dye (2-cyano-3-[5'''-(9-ethyl- 9H-carbazol-3-yl)-3',3'',3''',4-tetra-n-hexyl-[2,2',5',2'',5'',2''']-quater thiophen-5-yl]). Compared to bare $SnO_2$ film, the conversion efficiency is significantly improved from 0.22% to 3.13% after surface treatment of $SnO_2$ with $TiCl_4$, which is mainly due to the large increases in both photocurrent density from 1.33 to $9.46mA/cm^2$ and voltage from 315 to 634 mV. It is noted that little change in the amount of the adsorbed dye is detected from 1.21 for the bare $SnO_2$ to $1.28{\mu}mol/cm^2$ for the $TiCl_{4-}$ treated $SnO_2$. This indicates that the photocurrent density increased by more than 6 times is not closely related to the dye loading concentration. From the photocurrent and voltage transient spectroscopic studies, electron life time increases by about 13 order of magnitude, whereas electron diffusion coefficient decreases by about 3.6 times after $TiCl_4$ treatment. Slow electron diffusion rate offers sufficient time for regeneration kinetics. As a result, charge collection efficiency of about 40% before $TiCl_4$ treatment is improved to 95% after $TiCl_4$ treatment. The large increase in voltage is due to the significant increase in electron life time, associated with upward shift of fermi energy.