• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.161-161
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• 2013

본 연구에서는 백금 나노입자의 크기, 형상, 분포도에 따른 전기 화학적 효율을 평가하기 위해 계면활성제 농도를 달리하여 백금 나노입자를 합성하였다. 계면활성제로는 CTAB(cetyltrimethylammonium bromide)이 사용되었으며, 0.5 mM의 $H_2PtCl_6$의 백금 염을 환원시키기 위하여 유체 플라즈마 공정을 이용하였다. 공정 시간은 UV-vis 스펙트럼 결과를 토대로, 262 nm의 파장대에서 관찰된 LMCT(ligand-to-metal charge transfer) peak이 사라지는 시간을 기준으로 하여 공정을 진행하였다. 합성된 나노입자는 순환 전류-전압곡선(CV), TEM이미지와 XRD 분석을 이용하여 전기화학적 특성, 입자의 평균 크기 및 형상 변화를 비교 분석 하였다. 그 결과 CTAB을 넣지 않은 백금나노입자의 경우, CTAB을 넣고 제조한 백금 나노입자와는 달리 구의 형태로 뭉쳐있음을 관찰하였고, 이러한 백금 나노입자의 구조는 보다 높은 전기화학적 활성 특성을 가짐을 보였다.

• 대한공업교육학회지
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• v.32 no.2
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• pp.188-198
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• 2007

Platinum nanoparticles loading on carbon nanotube was carried out by impregnation of hexachloro platinate(IV) from hydrogen hexachloro platinate(IV) hydrate dissolved solution without using reduction agents, and heating the hexachloro platinate(IV) impregnated carbon nanotube up to $400^{\circ}C$. The amounts of impregnated hexachloro platinate(IV) on to carbon nanotube were measured with UV-visible spectrophotometer. The TG, XRD, and TEM analysis were performed to confirm the platinum particles loading and distribution on carbon nanotube. The average platinum particles size on carbon nanotube was under 2 nm by heating the hexachloro platinate(IV) up to $400^{\circ}C$ in spite of non-using reduction agents, while the average size increased due to the agglomeration of some particles by heating them up to $800^{\circ}C$. Therefore, uniformly distributed platinum nanoparticles loading on carbon nanotube can be obtained from simple impregnation of hexachloro platinate(IV) from solution and heating it up to $400^{\circ}C$.

• Korean Chemical Engineering Research
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• v.53 no.5
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• pp.540-544
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• 2015

A bath for electrodeposition of platinum nanoparitcles on low-cost graphite substrates was developed to attach nanoparticles directly onto a substrate, and electrochemical characteristics of the electrodeposition of platinum nanoparticles were investigated. The reaction mechanism was examined by the analysis of polarization behavior. Cyclic voltammetry measurements revealed that the elecrodeposition of platinum nanoparticles was limited by mass transfer. The chronoamperometric study showed an instantaneous nucleation mechanism during the electrodeposition of platinum nanoparticles on graphite. Because graphite is much cheaper than other carbon-based substrates, the electrodeposition of platinum nanoparticles on the graphite is expected to have useful applications.

• Resources Recycling
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• v.20 no.2
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• pp.67-73
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• 2011

In this study, for recovery of renewable noble metal from used stack of fuel cell, synthesis of platinum nano particle is established through effect of platinum solution concentration, pH value, reducing agent and dispersing agent at a volume ratio of 1 mM $H_2PtCl_6$:10 mM $NaBH_4$:8 mM Cl4TABr = 1:0.4:0.4(vol.%), pH4, $50^{\circ}C$, 160 rpm and 10min. Less than 5 nm platinum particles were synthesized using Pt leaching solution from used MEA of stack under same condition of method using simulated Pt solution. The characteristics of synthesized nano particles was illustrated by XPS analysis as the reduction of platinum ions into platinum metals(zero-valent).

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.9.1-9.1
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• 2011

나노입자는 벌크에 비해 월등히 큰 비표면적(surface-to-volume ratio)과 작은 사이즈에서 오는 양자효과로 인해 촉매나 나노 전자 소자 등 여러 분야에서 응용되고 있다. 특히 백금 나노입자는 수소나 메탄올의 산화, 산소환원 반응의 독보적인 촉매로서 연료전지의 산화극과 환원극의 촉매로 널리 활용되고 있다. 본 연구에서는 높은 가격의 백금의 사용량을 줄일 수 있는 합금 나노입자 촉매에 대한 연구의 일환으로 Pd, Au, Cu, Ag 등의 원소를 활용한 합금 나노입자에 대한 구조 및 열역학적 안정성에 대한 연구를 수행하였다. 다양한 합금에 대한 원자간 포텐셜을 개발하였고, 이를 기반으로 몬테카를로 및 분자동력학 시뮬레이션을 수행하여 Pd-Pt, Cu-Pt, Ag-Pt, Au-Pt 이원계 합금 나노입자의 다양한 원자 구조 및 형상에 따른 결합에너지와 열역학적 특성에 대하여 분석하였다.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.92.2-92.2
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• 2011

차세대 에너지로 연료전지가 각광을 받고 있는 현재, 세계 각국에서는 연료전지의 상용화를 위해 노력하고 있다. 그러나 촉매분야에서 백금계 촉매의 사용량의 문제에 따른 매장량 한계점과 귀금속이라는 문제점이 존재하기 때문에 이에 대하여 대책강구가 필요한 시점이다. 이에 백금 촉매의 활성을 증대하고자 나노 크기의 제어 연구가 진행되고 있다. 또한, 촉매의 구조적인 면에 따라 촉매의 활성이 달라지는 점을 착안하여 백금계의 나노 형상 조절 연구와 백금계 촉매를 대체할 비백금계의 촉매 개발 연구가 활발히 진행되어지고 있다. 이에 본 연구는 백금계 촉매 중 Pd을 polyol process에 의한 나노 형상 조절을 통하여 단위 질량당(or 단위 부피당)촉매의 활성을 높이고자 하였다. 여기서 새로이 도입된 환원제는 Glycerol을 이용하였으며, {111}면이 많이 드러난 Pd 나노입자를 형성하였다. 이에 따라 나노 형상 조절이 된 Pd촉매를 이용하여 상용화된 촉매(Pd/C(XC-72R))에 비하여 전기화학적인 특성의 차이와 Pd 촉매의 촉매적 특성의 효과를 보고자 한다.

• Journal of the Korean Chemical Society
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• v.54 no.3
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• pp.310-316
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• 2010

Nanoparticle with antimicrobial property has been applied to various fields. This study added silver/platinum nanoparticles to HEMA (2-hydroxyethylmethacrylate), NVP (N-vinyl pyrrolidone) and MMA (methylmethacrylate) in various concentrations and copolymerized by heating at $70^{\circ}C$ for 40 minutes, $80^{\circ}C$ for 40 minutes, and finally, $100^{\circ}C$ for 40 minutes. The particle size of used nano silver and platinum was 10 ~ 20 nm respectively. Using the polymer produced through the copolymerization process, the authors have produced a contact lens and measured the physical characteristics which showed water content of 34.29 ~ 39.00%, refractive index of 1.422 ~ 1.430, visible transmittance of 78.8 ~ 92.5% and tensile strength of 0.149 ~ 0.179 kgf. The ophthalmic lens material produced using silver/platinum nanoparticles satisfied the basic physical properties required for contact lens application.

• Resources Recycling
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• v.16 no.5
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• pp.36-40
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• 2007

Platinum plays an important role in many applications because of its extraordinary physical and chemical properties. All these applications require the use of platinum in the finely divided state. Therefore the preparation of platinum nanoparticles by reducing platinum-surfactant salt with reducing agent in the solution was investigated in this study. The net interaction between C14TABr and $H_2[PtCl_6]$ in aqueous solution results in the formation of $[C14TA]_2[PtCl_6]$. The concentration of C14TABr and the concentration of $H_2[PtCl_6]$ has to be above cmc and 0.32 mM, respectively in order to obtain complex-micelle aggregation for mono dispersed Pt particles. Pt particle size increases with increasing $H_2[PtCl_6]$ and C14TABr concentration. And the shape of Pt particles was well controlled with increasing surfactant concentration.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.673-678
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• 2010

In the present study, mixed carbon-supported platinum(Pt) nanoparticles were prepared by a chemical reduction method of Pt precursor solution on two types of carbon materials such as activated carbons(ACs) and graphite nanofibers(GNFs). Average crystalline sizes and loading levels of Pt metal particles could be controlled by changing a content of GNFs. The highest electroactivity for methanol oxidation was obtained by preparing the carbon supports having 15 wt% GNFs. Furthermore, with an increase of GNFs content from 0% to 15%, an electrical conductivity was changed from $10^{-4}S/cm$ to $10^{-1}S/cm$. By an introduction of 10 wt% GNFs additive, the electroactivity of platinum particles was enhanced, but was saturated in the case of 15 wt% GNFs contents. This was related with the fact that the electroactivity change was dependent on the electrical conductivity of mixed carbon supports and Pt particle deposition content or deposition morphology.

• Korean Chemical Engineering Research
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• v.56 no.5
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• pp.705-710
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• 2018

An electrochemical glucose sensor with enzyme-free was fabricated using Pt nanoparticles (Pt NPs) decorated CuO nanoflowers (CuO NFs). 3-D CuO nanoflowers film was directly synthesized on Cu foil by a simple hydrothermal method and Pt NPs were dispersed on the petal surface of CuO NFs through electrochemical deposition. This prepared sample was noted to Pt NPs-CuO NF. Morphology of the Pt NPs-CuO NFs layer was analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The electrochemical properties and sensing performances were investigated using cyclic voltammetry (CV) and chronoamperometry (CA) under alkaline condition. The sensor exhibited a high sensitivity, wide liner range and fast response time. Its excellent sensing performance was attributed to the synergistic effect of the Pt NPs and CuO nanostructure.