• Journal of the Korean Ceramic Society
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• v.37 no.12
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• pp.1135-1139
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• 2000

본 연구에서는 Pt/Sn $O_2$박막의 CO 감지특성을 향상시키기 위하여 표면 형상을 제어하였다. Pt/Sn $O_2$계 박막센서의 최적 동작온도는 175$^{\circ}C$이었다. Pt가 12초 동안 증착된 Sn $O_2$가 200ppm의 CO 가스에 대하여 1.23의 최대감도를 나타내었고, 그 이상의 Pt 증착시간 증가에 따라 Sn $O_2$위의 Pt의 coverage가 증가하여 센서의 감도를 감소시켰다. 다층박막(multi-layer thin film)의 단층의 Pt/Sn $O_2$복합체 위에 다시 Sn $O_2$및 Pt의 cluster 층들을 연속적으로 증착함으로서 제작되었다. 단지 하나의 Pt 층만을 증착한 Sn $O_2$막보다 다층의 Pt/Sn $O_2$막이 더욱 우수한 감도( $R_{air}$/ $R_{co}$=1.72, CO: 200 ppm)를 나타내었다. Pt/Sn $O_2$다층박막의 우수한 감도의 원인은 Pt와 Sn $O_2$사이의 계면적 증대 때문인 것으로 생각되어 진다.다.

• Korean Journal of Materials Research
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• v.22 no.7
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• pp.352-357
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• 2012

$SnO_2$-mixed and Sn-doped $TiO_2$ nanoparticles were synthesized via a hydrothermal process. $SnO_2$-mixed $TiO_2$ nanoparticles prepared in a neutral condition consisted of anatase $TiO_2$ nanoparticles(diamond shape, ~25 nm) and cassiterite $SnO_2$ nanoparticles(spherical shape, ~10 nm). On the other hand, Sn-doped $TiO_2$ nanoparticles obtained under a high acidic condition showed a crystalline phase corresponding to rutile $TiO_2$. As the Sn content increased, the particle shape changed from rod-like(d~40 nm, 1~200 nm) to spherical(18 nm) with a decrease in the particle size. The peak shift in the XRD results and a change of the c-axis lattice parameter with the Sn content demonstrate that the $TiO_2$ in the rutile phase was doped with Sn. The photocatalytic activity of the $SnO_2$-mixed $TiO_2$ nanoparticles dramatically increased and then decreased when the $SnO_2$ content exceeded 4%. The increased photocatalytic activity is mainly attributed to the improved charge separation of the $TiO_2$ nanoparticles with the $SnO_2$. In the case of Sn-doped $TiO_2$ nanoparticles, the photocatalytic activity increased slightly with the Sn content due most likely to the larger energy bandgap caused by Sn-doping and the decrease in the particle size. The $SnO_2$-mixed $TiO_2$ nanoparticles generally exhibited higher photocatalytic activity than the Sn-doped $TiO_2$ nanoparticles. This was caused by the phase difference of $TiO_2$.

• Journal of the Korean Magnetics Society
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• v.25 no.5
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• pp.156-161
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• 2015

The electronic structures of the potential candidate semiconductor nanoparticles for dye-sensitized solar cell (DSSC), such as $ZnSnO_3$ and $Zn_2SnO_4$, have been investigated by employing X-ray photoemission spectroscopy (XPS). The measured X-ray diffraction patterns show that $ZnSnO_3$ and $Zn_2SnO_4$ samples have the single-phase ilmenite-type structure and the inverse spinel structure, respectively. The measured Zn 2p and Sn 3d core-level XPS spectra reveal that the valence states of Zn and Sn ions are divalent (Zn 2+) and tetravalent (Sn 4+), respectively, in both $ZnSnO_3$ and $Zn_2SnO_4$. On the other hand, the shallow core-level measurements show that the binding energies of Sn 4d and Zn 3d core levels in $ZnSnO_3$ are lower than those in $Zn_2SnO_4$. This work provides the information on the valence states of Zn and Sn ions and their chemical bonding in $ZnSnO_3$ and $Zn_2SnO_4$.

• Journal of the Korean Ceramic Society
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• v.49 no.5
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• pp.448-453
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• 2012

Nitrogen-incorporated $SnO_2$ thin films were deposited by rf magnetron sputtering. Comparative structural, electrical and optical studies of thin films deposited by sputtering of the Sn metallic target and sputtering of the $SnO_2$ ceramic target were conducted. The $SnO_2$ thin films deposited by sputtering of the Sn metallic target had a higher electrical conductivity due to a higher carrier concentration than those by sputtering of the $SnO_2$ ceramic target. Structurally the $SnO_2$ thin films deposited by sputtering of the $SnO_2$ ceramic target had a better crystallinity and a larger grain size. This study confirmed that there were distinct and clear differences in electrical, structural, and optical characteristics between $SnO_2$ thin films deposited by reactive sputtering of the Sn metallic target and by direct sputtering of the $SnO_2$ ceramic target.

• Journal of Sensor Science and Technology
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• v.14 no.5
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• pp.297-301
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• 2005

Nanocrystalline SnO and $SnO_{2}$ powder have been prepared by hydrazine method. Sn-Hydrazine complex was formed by the reduction between aqueous $SnCl_{2}$ solution and hydrazine monohydrate. $SnO_{2}$ nano powder was prepared by the decomposition of Sn-Hydrazine complex at $450^{\circ}C$. When NaOH was added to Sn-hydrazine complex, SnO powder with nano-sheet morphology could be prepared. This can be attributed to the role of $OH^{-}$ ion as a reducing agent.

• 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.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.198-198
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• 2006

Tin doped $In_2O_3$ sputtering target is widely used to produce a various kinds of flat panel display because of high transmittance in visible region and high electrical conductivity. In2O3 and SnO2 powders were prepared by a homogeneous precipitation method using metal source, respectively, the calcining and sintering behavior of the indium-tin oxide(In2O3-SnO2) composite powders were studied. The tin oxide(SnO2) dispersion condition in ITO sputtering target was improved by increasing calcining temperature. And the tin oxide dispersion was also improved by reducing the tin oxide contents in the ITO target from 30 to 5wt%. SnO2 dispersion and densification of ITO target is very difficult to control due to sublimation of SnO2 at over 1150C.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.3
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• pp.487-492
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• 1998

Ultrafine particles of $SnO_2$ or $(Sn,Ti)O_2$ and thin films of $SnO_2$ were synthesized by introducing aqueous tin chloride solution into a high temperature argon inductively coupled plasma (ICP) generated under ambient pressure (the spray-ICP technique). As-deposited $SnO_2$ particles from each concentration of solution were all tetragonal $SnO_2$ crystallline phase and their mean size decreased in proportion to the increase of solution concentration. The mean size of $SnO_2$ particles was in the 10~40 nm range.

• Applied Chemistry for Engineering
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• v.5 no.2
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• pp.295-304
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• 1994

$Mo-V-O/SnO_2$(VM/Sn) and $SnO_2/Mo-V-O$(Sn/VM) catalysts have been prepared and characterized by XRD, BET, SEM and TPD of ammonia. The catalytic reaction of acrolein oxidation with these catalysts, in a continuous-flow fixed-bed reactor, showed that they had higher conversion of acrolein and higher yield of acrylic acid than those of Mo-V-O itself. The origin of the observed synergy studied by TPD, TPR and TPO is explained by the cooperation of $SnO_2$ and Mo-V-O at their interfaces where electrons flow from Mo-V-O phase to $SnO_2$ and $SnO_2$ produces spill-over oxygens, which, by being transported onto the surface of Mo-V-O, reoxidize the partially reduced active sites.

• Korean Journal of Materials Research
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• v.26 no.4
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• pp.222-227
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• 2016

Tin oxides have been studied for various applications such as gas detecting materials, transparent electrodes, transparent devices, and solar cells. p-type SnO is a promising transparent oxide semiconductor because of its high optical transparency and excellent electrical properties. In this study, we fabricated p-type SnO thin film using rf magnetron sputtering with an SnO/Sn composite target; we examined the effects of various oxygen flow rates on the SnO thin films. We fundamentally investigated the structural, optical, and electrical properties of the p-type SnO thin films utilizing X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV/Vis spectrometry, and Hall Effect measurement. A p-type SnO thin film of $P_{O2}=3%$ was obtained with > 80% transmittance, carrier concentration of $1.12{\times}10^{18}cm^{-3}$, and mobility of $1.18cm^2V^{-1}s^{-1}$. With increasing of the oxygen partial pressure, electrical conductivity transition from p-type to n-type was observed in the SnO crystal structure.