• 한국결정성장학회지
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• 제29권6호
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• pp.379-382
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• 2019

금 나노 입자의 합성은 폴리바이닐피롤리던(PVP)의 계면 활성제로 아스코르브 산(AC)에 의한 골드 솔트의 환원을 통해 수용액 환경을 만들었다. pH 제어에 의해 4 내지 20 nm의 크기 범위를 갖는 고분 산성 금 입자를 고수율로 제조하였다. 합성된 금 나노 입자의 구조적 및 광학적 특성은 투과 전자 현미경(TEM) 및 UV-vis 분광법에 의해 특성화되었다. 제조된 나노 입자는 효율적인 표면 강화 라만 산란(SERS) 특성을 나타내었고, 이들의 SERS 활성은 크기에 의존한다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.130-130
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• 2016

Bioinspired hierarchical nanostructures for self-cleaning s-tnwjurface and SERS substrates are investigated. The multi-level hierarchy is combined with CuO nanowire and additional nanoscale structures. CuO nanowire, which has extremely high aspect ratio, serves as a base structure of multi-level hierarchy and additional flower like structures are placed on the CuO nanowires. Since as-fabricated CuO nanostructures are hydrophilic, the surface is coated with perfluorooctyltrichlorosilane in order to change its wetting property to hydrophobic. While those CuO based nanostructures have a sufficient roughness for superhydrophobic characteristics, hierarchical nanoflowers on nanowire structures lead to a self-cleaning surface. Furthermore, flower like nanostructures provide reentrant curvatures, thus enabling oleophobic property. The surfaces has a repellency even for a tiny droplet (10 nL) of low surface tension liquids (~35 mN/m). On the on hands, nanoflowers provide many number of nanoscale gaps. After a thin layer of silver is deposited on the surface of CuO nanostructures, those nanoscale gaps act as hot-spot for surface enhanced Raman scattering (SERS). To analyze SERS enhancement of the surfaces, Raman shift is measured with varying molar density of 4-Mercaptopyridine from mM to pM. From these results, hierarchical CuO nanostructures are suitable for self-maintenance and cost effective SERS sensing applications.

• 진공이야기
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• 제4권3호
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• pp.12-15
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• 2017

Surface enhanced Raman scattering (SERS) is considered as one of promising medical and diagnostic technologies. The SERS effect is caused by the localized surface plasmon resonance (LSPR) from metal nanoparticles with narrow hot spots. The mechanism of LSPR, development of nanostructure fabrication, and corresponding researches are discussed. The flexible, label-free, low-cost, and highly-sensitive Au/ZnONRs/G is introduced. The Au/ZnONRs/G detects and distinguishes cataract, age-related macular degeneration, and diabetic macular edema from aqueous humor. Comprehension of SERS provides further improvement in bio sensing technology including early diagnosis and prolonged life expectancy.realize highly stretchable electrodes.

• Bulletin of the Korean Chemical Society
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• 제35권3호
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• pp.958-960
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• 2014

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.79-80
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• 2009

• 한국고분자학회지:고분자과학과기술
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• 제26권1호
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• pp.56-60
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• 2015

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2941-2948
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• 2011

A nanogap formed by a metal nanoparticle and a flat metal substrate is one kind of "hot site" for surface-enhanced Raman scattering (SERS). The characteristics of a typical nanogap formed by a planar Au and either an Au and Ag nanoparticle have been well studied using 4-aminobenzenethiol (4-ABT) as a probe. 4-ABT is, however, an unusual molecule in the sense that its SERS spectral feature is dependent not only on the kinds of SERS substrates but also on the measurement conditions; thus further characterization is required using other adsorbate molecules such as 1,4-phenylenediisocyanide (1,4-PDI). In fact, no Raman signal was observable when 1,4-PDI was selfassembled on a flat Au substrate, but a distinct spectrum was obtained when 60 nm-sized Au or Ag nanoparticles were adsorbed on the pendent -NC groups of 1,4-PDI. This is definitely due to the electromagnetic coupling between the localized surface plasmon of Au or Ag nanoparticle with the surface plasmon polariton of the planar Au substrate, allowing an intense electric field to be induced in the gap between them. A higher Raman signal was observed when Ag nanoparticles were attached to 1,4-PDI, irrespective of the excitation wavelength, and especially the highest Raman signal was measured at the 632.8 nm excitation (with the enhancement factor on the order of ${\sim}10^3$), followed by the excitation at 568 and 514.5 nm, in agreement with the finite-difference timedomain calculation. From a separate potential-dependent SERS study, the voltage applied to the planar Au appeared to be transmitted without loss to the Au or Ag nanoparticles, and from the study of the effect of volatile organics, the voltage transmission from Au or Ag nanoparticles to the planar Au also appeared as equally probable to that from the planar Au to the Au or Ag nanoparticles in a nanogap electrode. The response of the Au-Ag nanogap to the external stimuli was, however, not the same as that of the Au-Au nanogap.

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1405-1409
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• 2007

The potential-induced charge transfer of the dye (Bu4N)2[Ru(dcbpyH)2-(NCS)2] (N719) on Au, Ag, and Cu electrode surfaces has been examined by surface-enhanced Raman scattering (SERS) in the applied voltage range between 0.0 and ?0.8 V. N719 is assumed to have a relatively perpendicular geometry with its bipyridine ring on the metal surfaces. A strong appearance of the carboxylate band at ~1370 cm-1 indicates that the carboxyl group will likely be deprotonated on the metal surfaces. As the electric potential is shifted from ?0.8 to 0.0 V, the ν (NCS) band at ~2100 cm-1 on the electrode surfaces appears to undergo a shift in frequency and intensity change. This indicated that the charge transfer between the dye and metal electrode surfaces had occurred. Electric-field-dependent charge transfer differs somewhat depending on the type of metal surfaces as suggested from the dissimilar frequency positions of the ν (NCS) band.

• 한국전기전자재료학회논문지
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• 제32권6호
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• pp.462-465
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• 2019

Nanoscale gold particles have been intensively researched due to their potential applications in catalysis, electronics, plasmonics, and biological assays. In our study, we fabricated gold nanoparticles (NPs) that were synthesized in an aqueous environment via the reduction of $HAuCl_4$ by ascorbic acid (AC) with a sodium citrate (SC) surfactant. Highly monodispersed gold particles with sizes ranging from 123 to 184 nm were prepared in high-yield by a surfactant concentration. The structural and optical properties of the synthesized gold nanoparticles were characterized by transmission electron microscopy (TEM) and UV-vis spectroscopy. The prepared nanoparticles exhibited efficient surface-enhanced Raman scattering (SERS) properties that were dependent on their on size.

• 전기화학회지
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• 제16권1호
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• pp.46-51
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• 2013

전극과 용액 사이 계면에서 일어나는 전기화학 반응 현상을 보다 정확하게 이해하기 위하여 전기화학 반응과정을 분광학적 방법으로 실시간으로 모니터링 할 수 있는 전극으로도 작동할 뿐만 아니라 표면증강라만산란(SERS) 활성도 강한 금 마이크로쉘을 제조하였다. 기존에 보고된 금 마이크로쉘에서 핵으로 사용한 폴리스티렌의 경우 균일성이 떨어지고 유기용매에 약하며 독성이 있다. 이에 본 연구에서는 폴리스티렌 보다 균일한 구조를 가지고, 유기 용매에서도 사용 가능하며 무독한 실리카 비드를 이용하여 금 마이크로쉘을 만들고 높은 SERS 신호를 낼 수 있도록 최적화시켰다. $2{\mu}m$ 실리카 비드 표면에 서로 다른 양의 3-aminopropyl triethoxysilane (APTES)를 반응시켜 얻은 금 마이크로쉘에서 SERS 신호가 가장 월등히 증폭되는 조건을 비교한 결과 1% (v/v) APTES 조건에서 SERS 신호의 증폭이 가장 컸다. 표면증강라만산란 스펙트럼 및 전계방출형 주사전자현미경(FE-SEM) 이미지를 통해 금 마이크로쉘을 분석하였다.