• Korean Journal of Materials Research
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• v.22 no.10
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• pp.504-507
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• 2012

Synthesis of RGO (reduced graphene oxide)-CdS composite material was performed through CBD (chemical bath deposition) method in which graphene oxide served as the support and Cadmium Sulfate Hydrate as the starting material. Graphene-based semiconductor photocatalysts have attracted extensive attention due to their usefulness for environmental and energy applications. The band gap (2.4 eV) of CdS corresponds well with the spectrum of sunlight because the crystalline phase, size, morphology, specic surface area and defects, etc., of CdS can affect its photocatalytic activity. The specific surface structure (morphology) of the photocatalyst can be effective for the suppression of recombination between photogenerated electrons and holes. Graphene (GN) has unique properties such as a high value of Young's modulus, large theoretical specific surface area, excellent thermal conductivity, high mobility of charge carriers, and good optical transmittance. These excellent properties make GN an ideal building block in nanocomposites. It can act as an excellent electron-acceptor/transport material. Therefore, the morphology, structural characterization and crystal structure were observed using various analytical tools, such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. From this analysis, it is shown that CdS particles were well dispersed uniformly in the RGO sheet. Furthermore, the photocatalytic property of the resulting RGO-CdS composite is also discussed in relation to environmental applications such as the photocatalytic degradation of pollutants. It was found that the prepared RGO-CdS nanocomposites exhibited enhanced photocatalytic activity as compared with that of CdS nanoparticles. Therefore, better efficiency of photodegradation was found for water purification applications using RGO-CdS composite.

• Solar Energy
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• v.10 no.3
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• pp.53-59
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• 1990

[ $CdSe_xTe_{1-x}$ ] ($0{\le}x{\le}1$) thin films were deposited cathodically on Ti substrates in aqueous sulfric acid solution containing 1M $CdSO_4$ and 1mM$(TeO_2+SeO_2)$. The limiting current was observed in deposition potential ranging from -0.20 to -0.65 vs.Ag/AgCl ; although its value has changed a little depending on the mole ratio x, the limiting current was almost constant in deposition potential of -0.45V in spite of the change of mole ratio x. The crystal structure of the $CdSe_xTe_{1-x}$ thin films was cubic zinc-blonde in the range of mole ratio $x=0{\sim}0.8$, and hexagonal wurtzite in the mole ratio x=1 When the mole ratio changed from x=0 to x=0.8, diffraction peaks was shifted to the larger diffraction angle.

• Journal of the Korean Chemical Society
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• v.63 no.3
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• pp.160-165
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• 2019

A series of reactions between an amino alcoholic ligand, cis-2-((2-((2-hydroxyethyl)amino)ethyl)amino)cyclohexan-1-ol (HEAC), with the mixtures of group 12 metals including, $HgCl_2/CdCl_2$, $HgCl_2/CdI_2$, $ZnCl_2/CdCl_2$ and $ZnCl_2/CdCl_2/HgCl_2$ was experimentally and theoretically studied to determine the most stable product of these reactions. Furthermore, the Cambridge Structural Database (CSD) studies were done to evaluate the theoretical results. The products were characterized by elemental analysis, FT-IR, Raman, $^1H$ NMR spectroscopy and single-crystal X-ray diffraction. Based on these investigations a binuclear structure of cadmium, [$Cd_2(HEAC)_2({\mu}-Cl)_2Cl_2$] (1), is the most stable product that was formed in all studied reactions between HEAC and metals mixtures. In this structure, the cadmium atom has a $CdN_2O({\mu}-Cl)_2Cl$ environment and distorted octahedral geometry.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.275-275
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• 2009

CdTe(331)/Si(211) and CdTe(400)/Si(100) thin films have been grown by MOCVD(metal organic chemical vapor deposition) system for large scale of IFPAs(IR focal plane arrays). We have investigated the effect of various growth parameters on the surface morphology and structural quality. Single crystalline CdTe(331) films were grown by two stage growth method - low temperature buffer layer step and high temperature growth step. In other case, single crystal of CdTe(400) films were grown on a few atomic layer thickness of GaAs which is grown on Si(100) substrate by molecular beam epitaxy. The crystalline quality of the films was analyzed by X-ray diffraction. The surface morphology and crystal structure of CdTe films were characterized by optical microscope.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.57-57
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• 2010

Self assembled $Zn_{x-1}Cd_xS$ nanowires, synthesized on a Indium tin oxide coated glass substrate with low composition of Cd as x=0.09, were fabricated non-precursor via a co-evaporation method using of solid sources of CdS and ZnS. We studies that ZnCdS nanowires are dislocation-free and the single crystalline hexagonal wurtzite structure showed by transmission electron microscopy and selected area electron diffraction pattern. Cathode luminescence spectra showed an near band edge peak at 383nm originated from nanowires at 80K and 300K. Core level spectra of the Cd 3d, Zn 2p and S 2p in the ZnCdS nanorods were obtained by x-ray photoelectron spectroscopy. Prepared ZnCdS nanorods showed different shape with increase of substrate temperature at the growth.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.318-321
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• 2007

CdSe nanoparticles were prepared by chemical solution methods using $CdCl_2{\cdot}4H_2O$ (or $Cd(NO_3)_ 2{\cdot}4H_2O$) and $Na_2SeSO_3$. The characteristics of CdSe nanoparticles were controlled by the react ion time, reaction temperature and reaction method as well as the surfactants. Cetyltrimethyl ammonium bromide(CTAB) was used as a capping agent to control the chemical reactions in aqueous solution. Polyvinylalcohol(PVA) was used as a templet in sono-chemical method. CdSe nanoparticles synthesized in aqueous solution showed homogeneous size distribution with relatively stable surface. CdSe nanoparticles synthesized in non-aqueous solution containing diethanolamine(DEA) showed the structure transformation from cubic to hexagonal as the reduction temperature increased from 80 to $160^{\circ}C$. Core shell CdSe was synthesized by sono-chemical method. Characteristics of CdSe nanoparticles were analyzed using transmission electron microscopy(TEM), x-ray photoelectron spectroscopy(XPS), x-ray diffraction(XRD), UV-Vis absorption spectra, fourier transform infrared spectroscopy(FT-IR) and photoluminescence spectra spectroscopy(PL). This paper presents simple routes to prepare CdSe nanoparticles for solar cell applications.

• Analytical Science and Technology
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• v.14 no.6
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• pp.535-539
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• 2001

One-dimensional coordination polymer of cadmium(II) complex, $[Cd(SCN)_2(C_4H_6N_2]_n$, has been prepared and characterized by X-ray single crystallography. Structure analysis reveals that each cadmium(II) atom is six-coordinated in distorted octahedral fashion with $CdS_2N_4$ composition. $CdS_2N_4$ composition contains two S and two N atoms from four thiocyanates and tow N atoms from two 4-methylimidazole ligands. Central cadmium(II) atoms are run in parallel to the a-axis and are doubly bridged with neighboring cadmium(II) atoms by the thiocyanate and isothiocyanate ligands. Thus, this complex has a one-dimensional polymer structure in which the 4-methylimidazole is in the trans conformation.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.285-288
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• 2012

• Bulletin of the Korean Chemical Society
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• v.35 no.5
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• pp.1529-1532
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• 2014

• Bulletin of the Korean Chemical Society
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• v.18 no.8
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• pp.791-793
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• 1997