• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.5
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• pp.269-275
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• 2014

In this study, chemical bath deposition method was used to grow Zinc sulfide(ZnS) thin films from $NH_3/SC(NH_2)_2/ZnSO_4$ solutions at $90^{\circ}C$. ZnS thin films have been prepared onto ITO glass. The concentrations of $ZnSO_4$ and $NH_3$ were varied while the concentration of Thiourea was fixed in 0.52 M. Structural, optical, electrical characteristic of ZnS thin films were measured. The physical and optical properties of different ZnS thin films were influenced severely by the concentration of the two reacting chemicals. The optimal concentration of $ZnSO_4$ and $NH_3$ was 0.085 M and 1.6 M, respectively.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.2
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• pp.233-240
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• 2021

For the production of neodymium-doped zinc sulfide thin films in various amounts, zinc sulfide and neodymium were simultaneously deposited using an RF magnetron sputtering equipment to form a thin films, and rapid thermal annealing was performed at 400℃ for 30 minutes as a post-treatment process. The structure, shape, and optical properties of ZnS thin films having various neodymium doping contents (0.35at.%, 1.31at.%, 1.82at.% and 1.90at.%) were studied. The X-ray diffraction pattern was grown to a (111) cubic structure in all thin films. The surface and structural morphology of the thin films due to the neodymium doping content was explained through SEM and AFM images. Only elements of Zn, S, and Nd that do not contain other impurities were identified through EDAX. The transmittance and band gap of the prepared thin films were confirmed using the UV-vis spectrum.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 2000.06a
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• pp.35-58
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• 2000

The demand for sub-micrometer or nanometer functional ceramic powders with a better suspension behavior in aqueous media in increasing. Redispersible barium titanate (BT) nanocrystals, green light emitting Mn2+ doped Zn$_2$SiO$_4$ and ZnS nanoparticle phosphors were synthesized by a hydrothermal method or chemical precipitation with surface modification. The nanoparticle redispersibility for BT was achieved by using a polymeric surfactant. X-ray diffraction(XRD) results indicated that the BT particles are of cubic phase with 80 nm in size. XRD results of zinc silicate phosphor indicate that seeds play an important role in enhancing the nucleation and crystallization of Zn$_2$SiO$_4$ crystals in a hydrothermal condition. This paper describes and discuss the methods of surface modification, and the resulting related properties for BT, zinc silicate and zinc sulfide.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.26-26
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• 2002

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.213-214
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• 2013

• Transactions of the Korean hydrogen and new energy society
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• v.1 no.1
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• pp.9-14
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• 1989

Mixed photocatalyst containing cadmium sulfide and zinc sulfide was prepared on silica gel powder and Nafion film. Photo-irradiation of aqueous mixture containing the photocatalysis generated hydrogen by water cleavage reaction. Use of sodium sulfide as sacrificial reagent help the photo-reaction. Evolution of the hydrogen was measured by gas chromatographic analysis. Composition of the catalyst was determined by atomic absorption spectrophotometer. 0.2 mL of of hydrogen was generated per hour. The maximun catalytic activity was obtained after 8-12 hours later. Hydrogen generation efficiency by the two different catalytic system was compared and showed that the Nafion-based catalyst is more efficient than the silicagel-based catalyst for the photoreaction.

• Elastomers and Composites
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• v.53 no.2
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• pp.75-79
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• 2018

ZnS:Mn-glycine (ZnS:Mn-Gly) nanocomposites were synthesized by capping ZnS:Mn nanocomposites with glycine. Zinc sulfate heptahydrate ($ZnSO_4{\cdot}7H_2O$), glycine ($C_2H_5NO_2$), manganese sulfate monohydrate ($MnSO_4{\cdot}H_2O$), and sodium sulfide ($Na_2S$) were used as the source reagents. $ZnS:Mn-Gly-C_{60}$ nanocomposites were obtained by heating the ZnS:Mn-Gly nanocomposites and fullerene ($C_{60}$) at a 2:1 mass ratio in an electric furnace at $700^{\circ}C$ for 2 h. X-ray diffraction (XRD) was used to characterize the crystal structure of the synthesized nanocomposites. The photocatalytic activity of the $ZnS:Mn-Gly-C_{60}$ nanocomposites was evaluated, via the degradation of brilliant green (BG) dye under 254 nm irradiation, with a UV-vis spectrophotometer.

• Journal of Environmental Health Sciences
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• v.17 no.1
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• pp.39-49
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• 1991

고온에서 황화수소(H$_{2}$S)를 제거하기 위한 흡착제를 개발할 목적으로 ZnO에 $Fe_{2}O_{3}$를 5~50 atomic %까지 첨가시켜 제조한 다공성 흡착제와 황화수소와의 반응(sulfidation)을 thermogravimetric analyzer (Shimadzu DT-30)로 수행하였으며, 고정층세서 zinc ferrite 흡착제의 흡착능을 측정하였다. 반응온도는723$^{\circ}$K~973$^{\circ}$K범위이며, 반응기체는 황화수소(2vol.%)와 질소와 혼합기체로서 total gas flow rate는 200ml/min으로 고정시켰다. Grain Model을 사용하여 실험데이터를 분석한 결과 전화율이 낮을 때 zinc ferrite와 황화수소 반응의 율속단계는 화학반응이었고 황화수소 농도에 대해 1차 반응이었다. 실험한 흡착제 중 10 atomic %의 $Fe_{2}O_{3}$를 첨가하여 제조한 zinc ferrite형 흡착제가 반응속도, 흡착능, 그리고 재생성면에서 우수한 흡착제로 밝혀졌다.

• Clean Technology
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• v.19 no.3
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• pp.300-305
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• 2013

Zinc oxide (ZnO) and reduced graphite oxide (rGO) composites were synthesized and tested as adsorbents for the hydrogen sulfide ($H_2S$) adsorption at mid-to-high (300 to $500^{\circ}C$) temperatures. In order to investigate the critical roles of oxygen containing functional groups, such as hydroxyl, epoxy and carboxyl groups, attached on rGO surface for the $H_2S$ adsorption, various characterization methods (TGA, XRD, FT-IR, SEM and XPS) were conducted. For the reduction process for graphite oxide (GO) to rGO, a microwave irradiation method was used, and it provided a mild reduction environment which can remain substantial amount of oxygen functional groups on rGO surface. Those functional groups were anchoring and holding nano-sized ZnO onto the 2D rGO surface; and it prevented the aggregation effect on the ZnO particles even at high temperature ranges. Therefore, the $H_2S$ adsorption capacity had been increased about 3.5 times than the pure ZnO.

• Journal of the Korean Institute of Navigation
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• v.25 no.4
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• pp.435-442
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• 2001

A new technique to grow a manganese-doped zinc-sulfide(ZnS：Mn) has been proposed using the repeated deposition of the Hot Wall method. The optical characteristics and crystallinity for the ZnS and ZnS：Mn thin films deposited on a quartz glass substrate by the method were investigated. Also, The ZnS：Mn thin film elcetroluminescent devices were fabricated by the method to study luminescence characteristics. All films showed (111)-oriented cubic structure. By the repeated deposition, the deposition rates were decreased, and the optical characteristics and crystalline properties were improved, which clarifies that the method is effective to deposit the thin films with good crystallinity Futhermore, the crystallinity was more improved by the doping of Mn. Only one peak emission at around 585nm originating from Mn luminescent center is observed In the photoluminescent and electroluminescent spectra of ZnS：Mn films and the luminance of the ZnS：Mn-based thin film electroluminescent devices was obtained below 60cd/$m^2$ . The optical and crystalline properties, luminescence characteristics are discussed in terms of the effects of the repeated deposition and Mn-doping.