• 통합자연과학논문집
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• 제3권2호
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• pp.112-116
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• 2010

Prepared CdSe nanoparticles were systems, one of the most studied and useful nanostructures. Semiconductor quantum dots (QDs) have been the subject of much interest for both fundamental reseach and technical applications in recent years, due mainly to their strong size dependent properties and excellent chemical processibility. CdSe nanocrystals were synthesized by using sol-gel process. Synthesized CdSe quantum dots were studied to evaluate the optical, electronic and structural properties using UV-absorption, and photoluminescence (PL) measurement. Prepared CdSe nanoparticles were subjected to sense hydrofluoric acid. Photoluminescence was quenched upon adding of hydrofluoric acid.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2321-2324
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• 2013

An improved hybrid solar cell was obtained by focusing on the effects of ligand for CdSe nanoparticles, in the active layers. The performance was compared by mixing nanoparticles capped with pyridine or oleic acid for the acceptor material into poly(3-hexylthiophene):[6,6]-phenyl C61 butyric acid methyl ester based active layer. The solar cells with pyridine capped CdSe nanoparticles showed a power conversion efficiency of 2.96% while oleic acid capped CdSe nanoparticles showed 2.85%, under AM 1.5G illumination. Formation of percolation pathways for carrier transport and a reduction in the hopping event resulted in better performance of pyridine capped nanoparticles.

• 한국분말재료학회지
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• 제15권3호
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• pp.210-213
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• 2008

Elongated CdSe nanoparticles with a diameter of 3-7nm have been successfully synthesized using two surfactants of trioctylphospine (TOP) and hexadecylamine (HDA) at $160^{\circ}C$. The formation of elongated CdSe nanoparticles is possibly due to the cooperative effects from both the different binding capability of two surfactants (TOP and HDA) and intrinsically anisotropic crystal structure of the CdSe. The electron diffraction pattern of CdSe nanoparticles revealed the formation of wurzite phase. The CdSe samples showed red-shifted wavelength from 560 to 580nm with increasing the refluxing time due to the gradual growth of CdSe nanoparticles. The relatively broad absorption band can be attributed to the surface state of CdSe nanoparticles. The possible formation mechanism of elongated CdSe nanoparticles was proposed and the characteristics of CdSe have been discussed as well.

• 한국수소및신에너지학회논문집
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• 제16권2호
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• pp.130-135
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• 2005

Cadmium selenide is one of the group IIb-VI compounds, which is the promising semiconductor material due to its wide range of technological applications in optoelectronic devices such as photoelectrochemical cells, solid state solar cells, thin film photoconductors etc. CdSe has optical band gap of 1.7-1.8eV and proper conduction band edge for water splitting. CdSe films are coated with small thickness(20-50nm) nanocrystalline $TiO_2$ film by electrodeposition or chemical bath deposition methods and PEC properties of CdSe and CdSe/$TiO_2$ sandwich structure are studied. The photoactivity of CdSe and CdSe/$TiO_2$ films deposited on titanium substrate is studied in aqueous electrolyte of 1M NaOH solution. Photocurrent and photovoltage obtained were of the order of 2-4 mA/$cm^2$ and 0.5V, respectively, under the intensity of illumination of 100 mW/$cm^2$.

• 센서학회지
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• 제19권2호
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• pp.160-167
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• 2010

In this paper, we fabricated the optoelectronic device based on Cadmium selenide(CdSe) nanocrystal quantum dots (NQDs)/single-walled carbon nanotubes(SWNTs) heterostructure using dieletrophoretic force. The efficient charge transfer phenomena from CdSe to SWNT make CdSe-Pyridine(py)-SWNT unique heterostructures for novel optoelectronic device. The conductivity of CdSe-py-SWNT was increased when it was exposed at ultra violet(UV) lamp, and varied as a function of wavelength of incident light.

• 전기화학회지
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• 제14권4호
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• pp.225-230
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• 2011

Copper indium gallium selenide (CIGS) 기반 박막 태양전지는 저렴한 제작 단가 및 다른 박막 태양전지에 비해 높은 효율을 보여 실리콘 기반 태양전지의 차세대 태양전지로 각광을 받고 있다. 구성 요소 중 buffer 층은 window 층과 absorber 층 사이의 높은 밴드 갭(band gap)을 해소 해주는 역할을 한다. 기존의 cadmium sulfide(CdS)의 인체 유해성 때문에 이를 대신할 indium sulfide(In2S3)를 이용한 buffer 층의 연구가 활발히 진행되고 있다. 본 연구에서는 전기화학적인 방법을 통해 값싸고 간편하게 indium sulfide buffer 층을 전극 표면에 합성하는 연구를 진행하였다. Indium-Tin-Oxide(ITO) 전극표면을 sodium thiosulfate 및 indium sulfate의 혼합물 용액에 담그고 환원 전위를 인가하여 indium sulfide를 합성하였다. 크기가 다른 두 전압을 교대로 인가하여 확산 한계(diffusion limit)를 최소화 함으로써 표면에 균일한 조성을 가지는 buffer 층을 합성해 낼 수 있었다. 또한 합성 중 온도의 조절을 통해 buffer 층의 밴드 갭을 최적화 할 수 있었다. 이렇게 전기화학적으로 합성된 buffer 층은 X-선 광전자 분광법과 회절법의 분석을 통해 ${\beta}$-indium sulfide 결정구조를 가짐을 확인 하였다.