• 전기학회논문지
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• 제59권3호
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• pp.594-598
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• 2010

We studied on the field emission properties of double-walled carbon nanotubes (DWCNTs) coated with lead selenide (PbSe) nanoparticles. PbSe nanoparticles were uniformly attached on the surface of the DWCNTs by a simple chemical process. The PbSe-coated DWCNTs showed highly increased emission current density and enhanced emission stability over 20 h, compared with raw DWCNTs. We consider that the enhanced field emission properties of PbSe-coated DWCNTs were attributed to the increased field enhancement factor and lowered work function of the emitters.

• 대한화학회지
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• 제66권5호
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• pp.341-348
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• 2022

In this work, radio frequency magnetron sputtering was used to deposit zinc selenide thin films on p-type silicon (100) wafers and glass substrates in a high vacuum chamber. Several surface characterization instruments were implemented to study the thin films. X-ray photoelectron spectroscopy results revealed that oxidized Zn bound to Se (Zn-Se) at 1022.7 ± 0.1 eV becomes the dominant oxidized species when Se concentration exceeds 70%. Scanning electron microscopy coupled with energy dispersive spectroscopy showed that incorporating Se in Zn thin films will lead to formation of ZnSe grains on the surface. Contact angle measurements indicated that ZnSe-60 exhibited the lowest total surface free energy value of 24.94 mN/m. Lastly, ultraviolet-visible spectrophotometry and ultraviolet photoelectron spectroscopy data evinced that the energy band gap gradually increases with increasing Se concentration with ZnSe-70 having the highest work function value of 4.91 eV.

• Journal of Mechanical Science and Technology
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• 제17권12호
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• pp.2099-2106
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• 2003

In this paper, a novel fast response NDIR analyzer (FRNDIR), which uses an electrically pulsed semiconductor emitter and dual type PbSe detector for the PPM-level detection of carbon dioxide (CO$_2$) at a wavelength of 4.28 $\mu\textrm{m}$, is described. Modulation of conventional NDIR energy typically occurs at 1 to 20 Hz. To achieve real time high-speed measurement, the new analyzer employs a semiconductor light emitter that can be modulated by electrical chopping. Updated measurements are obtained every one millisecond. The detector has two independent lead selenide (PbSe) with IR band pass filters. Both the emitter accuracy and the detector sensitivity are increased by thermoelectric cooling of up to -20 degrees C in all semiconductor devices. Here we report the use of semiconductor devices to achieve improved performance such that these devices have potential application to CO$_2$ gas measurement and, in particular, the measurement of fast response CO$_2$ concentration at millisecond level.

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1803-1806
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• 2005

Formation of octahedral shaped PbSe quantum dots at higher synthesis temperature is being reported in this paper. The synthesis includes the reaction between lead oleate and trioctylphosphine selenide under inert gas conditions to produce PbSe. TEM, SEM, XRD and EDS were used to characterize the samples. The SEM exhibited the formation of spherical shaped nanocrystals at temperature below 140 ${^{\circ}C}$ and octahedral shaped nanoparticles at higher temperatures. Moreover, the TEM also showed the well resolved (111) lattice fringes proving that the nanocrystals were crystalline in nature. Synthesis of highly pure PbSe nanocrystals was another interesting aspect of this research.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2014년도 추계학술대회 논문집
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• pp.305-305
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• 2014

포토리소그래피와 도금 공정을 통해 PbSe 나노와이어를 합성하였다. PbSe은 광센서 및 열전 물질로 많이 알려져있다. 이러한 응용처에의 향상된 성능을 위해 본 연구에서는 PbSe 나노와이를 합성하였다. 합성에 사용된 방법인 포토리소그래피와 도금 공정은 반도체 산업 전반에 인프라가 잘 구축된 공정이며, 병렬 공정이다. 따라서 본 연구는 경제적이며 대량생산이 가능한 PbSe 나노와이어의 합성법을 제안한다.

• 분석과학
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• 제13권2호
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• pp.222-228
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• 2000

비분산 적외선 방식에 의한 대기 중 일산화 탄소 측정용 검출기를 제작하고, 감도 및 안정성을 조사하였다. 검출 감도를 향상시키기 위하여 동일 흡수셀 내에 3개의 반사거울을 장착하여 셀 안에서의 빛의 통과거리가 증가되도록 설계하였다. 50cm 길이의 셀 안에서 빛의 통과거리를 16m까지 늘릴 수 있도록 컴퓨터 모사에 의해 반사거울의 곡률반경 및 곡률중심, 셀 안에서의 위치 등을 산출하여 셀을 제작하였다. 빛의 경로와 광학적 특성은 모의 셀 안에서 laser beam alignment에 의해 확인하였다. 투과광의 검출에는 광전도성 PbSe센서를 사용하였으며, 센서소자는 열전냉각방식에 의해 냉각하였다. 제작된 일산화 탄소 검출기의 검출한계와 스팬 드리프트는 각각 0.24ppm과 0.03ppm(v/v)이었다.