• Bulletin of the Korean Chemical Society
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• 제18권9호
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• pp.972-976
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• 1997

Single phase ruthenium oxides with perovskite (ATi1-xRuxO3 (A=Ca, Sr)) and pyrochlore structure (Bi2Ru2O7, Pb2Ru2O6.5) have been prepared reproducibly by solid state reaction methods and their electrocatalytic activities for oxygen evolution have been examined by Tafel plots. Tafel slopes vary from a low value of 42 mV/decade up to 222 mV/decade at room temperature. The high exchange current densities and high Tafel slopes compared with those obtained from the RuO2 DSA electrode at the crystalline single phase metal oxide electrodes suggest that they are better electrocatalysts at low overpotentials. A favorable change in the Tafel slope for the oxygen evolution reaction occurs as the ruthenium content increases. Substitution of Ti for Ru in the perovskite solid solutions enhanced their chemical stability by losing marginal electrochemical activity.

• Bulletin of the Korean Chemical Society
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• 제14권6호
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• pp.682-686
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• 1993

The syntheses and reactivities with olefins of $[Ru^{II}(L_3)(L_2)OH_2]^{2+}$ $[L_3$= 2,6-bis(N-pyrazolyl)pyridine(bpp), 2,6-bis(3,5-dimethyl-N-pyrazolyl)pyridine $(Me_4bpp);\;L_2$= 2,2'-bipyridine(bpy), 4,4'-dimethyl-2,2'-bipyridine $(Me_2bpy)$] are described. Their spectral and redox properties in aqueous solution were investigated. Evidence for each one electron redox process for the $Ru^{IV}-Ru^{III}$ and $Ru^{III}-Ru^{II}$ couples has been obtained. Oxidation of $[Ru^{II}(bpp)(bpy)OH_2]^{2+}$ with $Ce^{IV}$ gave $[Ru^{IV}(bpp)(bpy)O]^{2+}$. The $[Ru^{IV}$= 0 complex is paramagnetic $({\mu}_{eff}=2.82)$ and the complexes $[Ru(L_3)(L_2)OH_2]^{2+}$ are robust catalysts for the oxidation of styrene, cyclohexene, and cyclooctene with cooxidant such as NaOCl. Product distributions and selectivities are discussed by varying the number of the substituted-methyl group in the ring.

• 전기화학회지
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• 제5권1호
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• pp.21-26
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• 2002

비정질 루테늄 산화물을 사용한 수퍼캐패시터를 개발하였다. 삼염화루테늄 수화물$(RuCl_3{\cdot}xH_2O)$로부터 제조한 비정질의 이산화루테늄 수화물$(RuO_2{\cdot}nH_2O)$을 사용하여 수퍼캐패시터 전극을 제조하였다. 집전체로는 티타늄 및 STS 304박막에 비해 보다 넓은 전위창을 가지는 탄탈륨 박막을 사용하였다. 제조한 전극과 4.8M 황산 전해액을 사용하여 수퍼캐패시터를 제조하였다. 전극의 비정전용량은 순환전위전류분석에서 미분 최대 값으로 산화 및 환원 과정 각각 710 및 $645\;F/g-RuO_2{\cdot}nH_2O$이었으며, 평균값은 $521\;F/g-RuO_2{\cdot}nH_2O$으로 나타났다. 수퍼캐패시터를 포화카로멜기준전극에 대하여 0.5 V로 protonation level을 조정하고, 충방전 시험한 바, $151\;F/g-RuO_2{\cdot}nH_2O$의 비정전용량을 나타내었다.

• 분석과학
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• 제8권4호
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• pp.481-486
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• 1995

Quenching experiments by photoinduced electron transfer between a charged donor and a neutral acceptor were carried out in acetonitrile, dichloromethane and mixed solvents of acetonitrile and dichloromethane. Tris(2, 2'-bipyridine) ruthenium(II) ($[Ru(bpy)_3]^{2+}$) which has 2+ charge and dicyanobis (2, 2'-bipyridine) ruthenium(II) ($Ru(bpy)_2(CN)_2$) which has no charge were used as electron donors, and a series of tris(${\beta}$-diketonato) ruthenium (III) was used as acceptor. In dichloromethane, $[Ru(bpy)_3]^{2+}$ and its counter ions ($ClO{_4}^-$) form ion pair. In the estimate of ${\Delta}G$ of electron transfer, the electrostatic potential between counter ions and product ion pair produced by electron transfer must be taken into account. A similar effect of counter ions was found in mixed solvents of 10, 30, 50, 70 and 90% acetonitrile ratio in volume. The effect of counter ion on ${\Delta}G$ became smaller with the increase in acetonitrile ratio. The result in mixed solvents suggests that $[Ru(bpy)_3]^{2+}$ and its counter ions form ion pair even in 90% acetonitrile solution.

• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1341-1345
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• 2011

A novel ruthenium(II) complex, [$RuCl_2(DMSO)_2$(PhenTPy)] has been synthesized by the condensation of $RuCl_2(DMSO)_4$ with (1-(1,10-phenanthrolinyl)-2,5-di(2-thienyl)-1H-pyrrole)[PhenTPy] in $CHCl_3$ solution. The [$RuCl_2(DMSO)_2$(PhenTPy)] complex modified electrode was fabricated through the electropolymerization of the monomer in a 0.1 M tetrabutylammonium perchlorate (TBAP)/$CH_2Cl_2$ solution, to take advantage of the electronic communication between metal ion center by the conjugated backbone. The UV-visible spectroscopy (UV), mass spectrometry (MS), and cyclic voltammetry (CV) were employed to characterize the [$RuCl_2(DMSO)_2$(PhenTPy)] complex and its polymer (poly-Ru(II)Phen complex). The poly-Ru(II)Phen complex modified electrode exhibited an electrocatalytic activity to the oxidation of acetaminophen and the catalytic property was used for the analysis of acetaminophen at the concentration range between 0.09 and 0.01 mM in a phosphate buffer solution (pH 7.0).

• 대한화학회지
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• 제62권4호
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• pp.269-274
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• 2018

금속산화물 고분자 복합재료전극 제조기법을 수소이온 감응성이 높은 $RuO_2$에 적용하여 표면연마가 가능한 나노 $RuO_2$ 복합재료 pH전극을 제조하였다. $RuO_2$ 함량 53 wt%을 가지는 나노 $RuO_2$ 복합재료 전극의 경우 나노 $IrO_2$ 복합재료 전극과 비슷한 수소이온 감응특성을 나타내었다. pH 1~9의 범위에서 이론치에 가까운 -58.7 mV/pH의 감응기울기, 1초 이하의 감응속도, 평균 $-57.0{\pm}0.3mV/pH$ (n=5)의 표면재생성, 장기 안정성 등 제반 특성과 전기화학적으로 활성이 높은 화학종에 의한 방해효과도 비슷하게 나타났다. 그러나 pH 10 이상의 염기성 용액에서의 감응기울기와 감응속도는 나노 $IrO_2$ 복합재료전극에 비하여 현저히 떨어지는 결과를 보였으며 이는 복합재료 매질 속의 금속산화물 함량에 따른 물리적 성질 차이에 따른 것으로 추측된다.

• 한국전기전자재료학회논문지
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• 제15권10호
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• pp.865-869
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• 2002

The structural and electrical properties of PZT (lead zirconate titante) thin films grown on Pt (platinum) and Ru/Ru $O_2$(ruthenium/ruthenium oxide) electrodes were investigated. Thin films of PZT were deposited on a variety of electrodes using the rf-magnetron sputtering process. PZT films exhibited polycrystalline structure with strong PZT (100) plane and weak (211) plane for an optimizied Pt electrode and (100), (101), (111), (200), (210), (211) planes for Ru/Ru $O_2$. Switching polarization versus fatigue characteristic of Pt/Ti electrodes showed 20% degradation up to 1 $\times$ 10$_{9}$ cycles. No significant fatigue was observed in the films on Ru/Ru $O_2$ electrodes up to Ix109 test cycles. The results show that the new Ru/Ru $O_2$ bottom electrodes are expected to reduce the degradation of ferroelectric fatigue.

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2329-2337
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• 2009

Three heteroleptic ruthenium sensitizers, Ru(L)($L^1)(NCS)_2$ [L = 4,4'-dicarboxylic acid-2,2'-bipyridine, Ru-T1: $L^1$ = (E)-2-(4'-methyl-2,2'-bipyridin-4-yl)-3-(thiophen-2-yl)acrylonitrile, Ru-T2: $L^2$ = (E)-3-(5'-hexyl-2,2'-bithiophen-5- yl)-2-(4'-methyl-2,2'-bipyridin-4-yl)acrylonitrile, and Ru-T3: $L^3$ = (E)-3-(5"-hexyl-2,2':5',2"-terthiophen-5-yl)-2- (4'-methyl-2,2'-bipyridin-4-yl)acrylonitrile)], were synthesized and used as photosensitizers in nanocrystalline dyesensitized solar cells (DSSCs). The introduction of the 3-(5-hexyloligothiophen-5-yl)acrylonitrile group increased the conjugation length of the bipyridine donor ligand and thus improved their molar absorption coefficient and light harvesting efficiency. DSSCs with the configuration of Sn$O_2$: F/Ti$O_2$/ruthenium dye/liquid electrolyte/Pt devices were fabricated using these Ru-$T1{\sim}T3$ as a photosensitizers. Among the devices, the DSSCs composed of Ru-T2 exhibited highest power conversion efficiency (PCE) of 2.84% under AM 1.5 G illumination (100 mW/$cm^2$).

• 분석과학
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• 제23권5호
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• pp.498-504
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• 2010

열 이온화 질량분석을 이용한 루테늄(Ru) 동위원소 비 측정은 루테늄의 이온화 포텐셜이 높고 산화상태로 휘발이 일어나 시료가 쉽게 소모되어 안정된 이온피크를 얻기가 어렵다. 따라서 이온화 효율을 높이고 안정적 이온생성을 위한 실험과 질량분석에 사용되는 레늄(Re) 필라멘트에 함유된 불순물들에 의한 동중원소 영향을 검토하였다. 질량분석에서 double filament를 사용하는 것 보다는 single filament를 사용하는 것이 더 안정적 이온 피크를 얻을 수 있었을 뿐만 아니라 몰리브데넘(Mo)에 의한 동중원소 영향도 작았다. 또한 필라멘트 온도를 필요이상 높이면 높일수록 동중원소 영향이 큼을 알 수 있었다. 즉, 불순물로 함유된 Mo이 Ru 동위원소 비 측정에 큰 영향을 주었다. 특히 필라멘트 온도를 일정한 시간 간격을 두고 서서히 올려주는 것이 안정된 피크를 얻는데 매우 중요함을 알 수 있었다. Mo으로부터 오는 동중원소 영향을 $^{94}Mo/^{99}Ru$ 비를 측정하여 보정함으로써 Ru 동위원소 비를 정확히 측정할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제31권11호
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• pp.3145-3150
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• 2010

Ruthenium catalysts modified by selenium have been introduced as alternative materials to Pt in Direct methanol fuel cells (DMFCs). RuSe nano-particles were synthesized on the Vulcan XC72R carbon supports via polyol method. The prepared catalysts were electrochemically and physically characterized by cyclic voltammetry (CV,) linear sweep voltammetry, methanol tolerance test, X-ray diffraction (XRD), Transmission electron microscopy (TEM), Energydispersive Spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS). Increasing the Se concentration up to 20 at % increased the electro-catalytic activity for the oxygen reduction. By increasing Se amount, Ru metallic form on the surface was increased. The $Ru_{80}Se_{20}$/C catalysts showed the highest oxygen reduction reaction (ORR) activity and outstanding methanol tolerant property in half cell tests as well as single cell test.