• 공업화학
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• 제18권5호
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• pp.467-474
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• 2007

팔라듐과 금 나노입자 등이 첨착된 높은 비표면적을 갖는 Polyacrylonitrile (PAN)계 활성탄소섬유(ACF: Activated Carbon Fiber)를 제조하였다. 여러 첨착 ACF에 대하여 BET, FE-SEM, TEM, XPS 등으로 비표면적과 기공부피, 미세구조, 시간에 따른 산소관능기의 표면변화를 관찰하였으며 $SO_2$에 대한 흡착성능을 연구하였다. 그 결과 첨착과정으로 인하여 총 기공부피 대비 미세기공 부피는 95.5%에서 30.5~43.7%로 대부분 감소하였으며, 산소관능기의 표면변화는 대기중에서 시간이 경과함에 따라 나노입자보다 금속염의 산소관능기 변화가 컸음을 알 수 있었다. 또한 Au 나노입자와 금속염을 첨착한 ACF의 $SO_2$ 파과시간은 무첨착 ACF에 비하여 크게 변하지 않았으나, 100 ppm의 Pd 나노입자를 첨착한 ACF는 $SO_2$ 파과시간이 880 s로 흡착성능이 우수하였다. 이러한 결과로 볼 때 $SO_2$ 흡착성능은 시간에 따른 산소관능기의 표면 변화와 연관성이 있다고 볼 수 있으며, PAN계 활성탄소섬유에 적정한 농도의 Pd 나노입자 첨착은 촉매작용으로 인하여 $SO_2$ 흡착 성능을 증가시키는 것으로 판단된다

• 한국수소및신에너지학회논문집
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• 제27권3호
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• pp.264-269
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• 2016

A simple dry chemical approach was developed in order to load palladium (Pd) as a promoter on Pt/gas diffusion electrode (GDE) for polymer electrolyte membrane fuel cell (PEMFC). Palladium(II) bis (acetylacetonate), $Pd(acac)_2$ was sublimed, penetrated into Pt/GDE and then reduced to Pd nanoparticles simultaneously without any reducing agent and any solvent in a glass reactor of $N_2$ atmosphere at $180^{\circ}C$ for 3, 5 and 15 min. Pd distribution was analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), and I-V curve was estimated by using a unit cell with $5{\times}5cm^2$ active area.

• 한국세라믹학회지
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• 제43권4호
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• pp.224-229
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• 2006

Ag-Pd alloy nanoparticles were prepared by a chemical reduction method using hydrazine $(N_2H_4)$ as a reductant in $AgNO_3\;and\;Pd(NO_3)_2$ aqueous solutions. Characterization of these particles by X-ray powder diffraction revealed a bimetallic and crystalline silver-palladium alloy. The average size of the particles was influenced not by the reductant $(N_2H_4)$ concentration, but the concentration of the starting materials $(AgNO_3\;and\;Pd(NO_3)_2)$.

• Bulletin of the Korean Chemical Society
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• 제28권10호
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• pp.1746-1750
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• 2007

The second-order scattering (SOS) phenomenon of the interaction of Pd nanoparticles with protein was reported and a simple, sensitive, palladium nanoparticle-based assay for trace amount of protein with SOS technique was developed. The SOS intensities were significantly enhanced due to the interaction of Pd nanoparticles with bovine serum albumin (BSA) or human serum albumin (HSA) at pH 3.5 or 4.0, respectively. The maximum SOS peak appeared at 260/520 nm (λex/λem). The optimal experiment conditions, affecting factors and the influence of some coexisting substances were checked. The SOS intensity increased proportionally with the increase of Pd concentration below 3.0 × 10?5 mol·L?1, while declined gradually above 4.0 × 10?5 mol·L?1. BSA within the range of 0.01-2.6 μg·mL?1 and HSA of 0.01-1.7 μg·mL?1 can be detected with this method and the detection limits were 2.3 and 11.2 ng·mL?1, respectively. The method was successfully applied to the quantitative detection of total protein content in human serum samples with the maximum relative standard deviation (RSD) lower than 2.6% and the recoveries over the range of 99.5-100.5%.

• Bulletin of the Korean Chemical Society
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• 제35권7호
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• pp.1979-1984
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• 2014

We have developed an efficient method to generate highly active Pd and PdO nanoparticles (NPs) dispersed on graphene and graphene oxide (GO) by an impregnation method combined with thermal treatments in $H_2$ and $O_2$ gas flows, respectively. The Pd NPs supported on graphene (Pd/G) and the PdO NPs supported on GO (PdO/GO) demonstrated excellent carbon-carbon cross-coupling reactions under a solvent-free, environmentally-friendly condition. The morphological and chemical structures of PdO/GO and Pd/G were fully characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). We found that the remarkable reactivity of the Pd/G and PdO/GO catalysts toward the cross-coupling reaction is attributed to the high degree of dispersion of the Pd and PdO NPs while the oxidative states of Pd and the oxygen functionalities of graphene oxide are not critical for their catalytic performance.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.175.2-175.2
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• 2014

Graphene (G) has been modified with palladium, copper, and manganese oxide nanoparticles (NPs), and their catalytic applications have been studied in C-C coupling reactions and methylmercaptan (CH3SH) decomposition reactions. In this research, graphite oxide (GO) sheets were exfoliated and oxidized from graphite powder and impregnated with metal precursors including Pd2+, Cu2+, and Mn2+. The thermal treatments of the metal impregnated GO in preferred gas environments produced Pd NPs on graphene (Pd/G), PdO NPs on GO (PdO/GO), and CuOx and MnOx NPs on graphene (CuOx/MnOx/G). In case of Pd/G and PdO/GO, the TEM images show that, although the mean size of the Pd NPs changed significantly before and after the C-C coupling reaction, that of the PdO NPs didn't, implying that the PdO/GO was superior to Pd/G in terms of the recyclability. Also, we demonstrate that the CuOx/MnOx/G exerts the excellent catalytic efficiency in CH3SH decomposition reaction comparing with conventional catalysts. The chemical and electronic structural changes were investigated using XRD and XPS.

• 한국수소및신에너지학회논문집
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• 제29권3호
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• pp.243-250
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• 2018

Zinc oxide (ZnO) nanorods were grown on a palladium (Pd) activated polyacrylonitrile (PAN) fiber where Pd activation was carried out in advance by the following dry process: palladium(II) bis(acetylacetonate), $Pd(acac)_2$ was sublimed, penetrated into the surface of PAN fiber and spontaneously reduced to Pd nanoparticles at $180^{\circ}C$ for various times under a nitrogen atmosphere. ZnO nanorod morphology was observed by a scanning electron microscopy (SEM) and the elemental composition was confirmed by energy-dispersive X-ray spectroscopy (EDS). The crystalline structure of ZnO nanorods was analyzed by X-ray diffraction (XRD) analysis showing Wurtzite structure consisting of hexagonal lattice. Sulfur removal characteristics were evaluated.

• 센서학회지
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• 제33권5호
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• pp.288-297
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• 2024

Currently, numerous studies are being conducted on metal oxide semiconductor (MOS) gas sensors for hydrogen detection, using Palladium (Pd) and Pd-based alloy nanoparticles (NPs) owing to their hydrogen absorption ability. Furthermore, several studies have reported that Pd-Iridium (Ir) alloys possess high hydrogen absorption capabilities in their bulk state. However, Ir growth is limited to above 2 nm and it does not mix extensively with other metals. Furthermore, as the hydrogen absorption capacity decreases with the reduction in particle size, it is necessary to synthesize nanoparticles of an appropriate size. Therefore, the synthesis of Pd-Ir alloy NPs larger than 10 nm is challenging. In this study, we report the synthesis of Pd-Ir NPs with an average diameter of 19 nm using a hydrothermal technique for the first time and fabricated Pd-Ir alloy NPs through calcination at 500℃ in Ar and air. To confirm alloy formation and oxidation behavior, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were performed. In addition, we synthesized Pd-Ir@CeO₂ core-shell nanoparticles (CSNPs) as hydrogen gas-sensing materials. The Pd-Ir core was partially oxidized during heat treatment at 500℃ in air, and Pd-Ir@CeO₂ CSNPs were finally changed into Pd-Ir(alloy)/PdO-IrO₂@CeO₂ CSNPs, which exhibited higher sensitivity and selectivity toward H₂ gas compared to totally oxidized PdO-IrO₂@CeO₂ CSNPs and pure CeO₂ NPs. The enhanced gas-sensing performance was attributed to the hydrogen absorption effect of the Pd-Ir(alloy) NPs.

• 한국수소및신에너지학회논문집
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• 제27권3호
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• pp.270-275
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• 2016

A simple solid state incorporation method was employed in order to incorporate Pd nanocatalyst into a Nafion film for polymer electrolyte membrane fuel cell (PEMFC) via the reduction of palladium (II) bis (acetylacetonate), $Pd(acac)_2$. It was sublimed, penetrated into Nafion film and then reduced to Pd nanoparticles simultaneously in a glass reactor of N2 atmosphere at $180^{\circ}C$ for 1, 3 and 5 min. This reaction was took place without any reducing agent and any solvent. The morphology of the Pd nanoparticles was observed by transmission electron microscopy (TEM), and Pd distribution was analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). And 23% modification of tensile strength of Pd/Nafion composite film was measured by universal testing machine and I-V curve was estimated by using a unit cell with $5{\times}5cm^2$ active area.

• Composites Research
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• 제32권2호
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• pp.85-89
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• 2019

나노입자에 기반한 화학 촉매 반응 효율성에는 크기, 형태 및 조성이 중요한 영향을 미치는 것으로 알려져 있다. 이에 대한 체계적인 비교를 위해 갈바닉 치환 반응을 통해 100 nm 직경의 요철형 표면 구조를 갖는 금, 백금, 팔라듐 나노플레이트에 대한 정량적인 분석 조건 형성이 가능하였으며, 4-나이트로페놀과 4-나이트로아닐린을 대상으로한 촉매 반응 진행을 분광분석법을 통해 확인할 수 있었다. 이로부터 동일 형태 및 형태에서 구성 원소에 따라 확연히 다른 Pd > Au > Pt의 촉매성 환원 반응 효율을 보임을 관찰할 수 있었으며, 기질의 형태에 따라 추가적인 영향을 받음을 관찰 가능하였다.