• 제목/요약/키워드: Platinum(Pt)

검색결과 487건 처리시간 0.029초

Ethylcellulose와 금속염을 이용한 고분자-금속 착체막의 제조 및 기체투과특성 (Preparation of Polymer-Metal Complexed Membranes using Ethylcellulose and Metal salts, and Their Characteristics of Gas Separation.)

  • 변홍식;서성호;박병규;홍병표;백승욱;박영규
    • 멤브레인
    • /
    • 제13권3호
    • /
    • pp.200-209
    • /
    • 2003
  • Ethyl cellulose(EC)와 platinum(II) acetylacetonate(Pt), rhodium(III)acetylacetonate(Rh)를 이용하여 용매증발법으로 고분자-금속 착체막을 제조하였다. 이때 최종 분리막의 제막조건을 최적화하기 위하여 금속염의 조성을 변화시켰다. (0.3-4.0 wt%). FTIR을 이용하여 EC-금속착체막을 분석하였으며 SEM을 이용하여 막의 구조를 관찰하였다. 그리고 산소, 질소, 이산화탄소, 메탄 가스들의 투과성능을 조사하였다. 금속염들은 모든 가스들의 선택도의 감소없이 투과도를 향상시킨다는 것을 알 수 있었다 그러나 Pt의 경우 산소와 질소가스의 투과성능에 더 영향이 있었으며, Rh은 이산화탄소와 메탄가스의 투과도에 더 영향이 있음을 알 수 있었다. EC-Pt 착체막의 경우에는, Pt의 산소와의 친화력특성에 기인하여 산소/질소의 선택도가 증가(37%)하는 것을 보여주었다.

폴리올법으로 제조된 Pt/C 촉매의 연료전지 적용을 위한 나노 입자 크기제어 (Nano particle size control of Pt/C catalysts manufactured by the polyol process for fuel cell application)

  • 허준;윤혁준;최지훈;문채린;최순목
    • 한국표면공학회지
    • /
    • 제56권6호
    • /
    • pp.437-442
    • /
    • 2023
  • This research aims to enhance the efficiency of Pt/C catalysts due to the limited availability and high cost of platinum in contemporary fuel cell catalysts. Nano-sized platinum particles were distributed onto a carbon-based support via the polyol process, utilizing the metal precursor H2PtCl6·6H2O. Key parameters such as pH, temperature, and RPM were carefully regulated. The findings revealed variations in the particle size, distribution, and dispersion of nano-sized Pt particles, influenced by temperature and pH. Following sodium hydroxide treatment, heat treatment procedures were systematically executed at diverse temperatures, specifically 120, 140, and 160 ℃. Notably, the thermal treatment at 140 ℃ facilitated the production of Pt/C catalysts characterized by the smallest platinum particle size, measuring at 1.49 nm. Comparative evaluations between the commercially available Pt/C catalysts and those synthesized in this study were meticulously conducted through cyclic voltammetry, X-ray diffraction (XRD), and field-emission scanning electron microscopy-energy dispersive X-ray spectroscopy (FE-SEM EDS) methodologies. The catalyst synthesized at 160 ℃ demonstrated superior electrochemical performance; however, it is imperative to underscore the necessity for further optimization studies to refine its efficacy.

유도 결합 BCl$_{3}$/Cl$_{2}$ 플라즈마내에서 Pt 박막의 건식 식각 (Dry etching of pt thin film in inductive coupled BCl$_{3}$/Cl$_{2}$ plasmas)

  • 김남훈;김창일;권광호;장의구
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1998년도 하계종합학술대회논문집
    • /
    • pp.375-378
    • /
    • 1998
  • Platinum thin film which hardly form volatile compounds with any reactive gas at normal process temperature was etched in inductive coupled BCl$_{3}$/Cl$_{2}$ plasma. The etch rate of platinum thin film increased with increasing Cl$_{2}$/(Cl$_{2}$ + BCl$_{3}$) ratio. That reasoned increasing of ion current density.

  • PDF

측온저항체 온도센서용 백금박막의 형성에 관한 연구 (The study on formation of platinum thin films for RTD temperature sensor)

  • 정귀상;노상수
    • E2M - 전기 전자와 첨단 소재
    • /
    • 제9권9호
    • /
    • pp.911-917
    • /
    • 1996
  • Platinum thin films were deposited on Si-wafer by DC rnagnetron sputtering for RTD (resistance thermometer devices). We investigated the physical and electrical characteristics of these films under various conditions, the input power, working vacuum, temperature of substrate and also after annealing these films. The deposition rate was increased with increasing the input power but decreased with increasing Ar gas pressure. The resistivity and sheet resistivity were decreased with increasing the temperature of substrate and the annealing time at 1000.deg. C. At substrate temperature of >$300^{\circ}C$, input power of 7 w/cm$^{2}$, working vacuum of 5 mtorr and annealing conditions of 1000.deg. C and 240 min, we obtained 10.65.mu..ohm..cm, resistivity of Pt thin films and 3800-3900 ppm/.deg. C, TCR(temperature coefficient of resistance). These values are close to the bulk value. These results indicate that the Pt thin films deposited by DC magnetron sputtering have potentiality for the development of Pt RTD temperature sensor.

  • PDF

자동차 연료전지 진단 및 백금 촉매제 최소화에 대한 연구 (Methods for Diagnosis and Minimum PT-Loading of PEM Fuel Cell Stack)

  • 유승열;이용현
    • 전기학회논문지
    • /
    • 제62권1호
    • /
    • pp.105-108
    • /
    • 2013
  • To resolve global environmental problems, many automobile companies are making a great deal of effort to develop so-called green-cars. One of the solutions is an electric vehicle equipped with the PEMFC (Proton Exchange Membrane Fuel Cell) stack. However, the cost of the stack, at the moment, is still too high. This obstacle must be resolved for commercialized fuel cell cars. One of the reasons for high cost is a relatively large amount of Pt (platinum) in the membrane. In this paper, a method for reducing the Pt-loading is introduced. Furthermore, the durability of the stack will be important for a company to stay competitive in world markets (in the future). For this, the diagnosis of the stack must be conducted on-line. Some diagnosis methods as key technology are also introduced in this paper.

Synthesis and Properties of Diamineplatinum(II) and Diamineplatinum(IV) Complexes Involving Cyclohexylidenemalonate Ligand

  • 정철수;이성실;김관묵;정옥상;손윤수
    • Bulletin of the Korean Chemical Society
    • /
    • 제16권10호
    • /
    • pp.981-984
    • /
    • 1995
  • New diamineplatinum(Ⅱ) complexes of cyclohexylidenemalonate (chm) ligand, A2Pt(OOC)2C=C(CH2)4CH2 (1, A2=ethylenediamine (en); 2, A2=propylenediamine (pn); 3, A=NH3; 4, A=isopropylamine (ipa)) have been prepared. Their oxidation with H2O2 has led to the corresponding dihydroxoplatinum(Ⅳ) complexes: cis, cis, trans-A2Pt((OOC)2C=C(CH2)4CH2)(OH)2 (5, A2=en; 6, A2=pn; 7, A=NH3; 8, A=ipa). The title complexes have been characterized by means of various spectroscopies and X-ray crystallography. 5 crystallizes in the monoclinic space group P21/a (Z=4) with a=12.098(7) Å, b=9.552(2) Å, c=16.258(4) Å, β=98.03(5)° and V=1860(1) Å3. The structure was refined to R=0.074. The local geometry around platinum atom is approximately octahedral with each hydroxide group in trans position. These platinum complexes are stable in aqueous solution. Pt(Ⅳ) complexes are readily reduced to the corresponding Pt(Ⅱ) complexes by ascorbic acid.

Cycloplatinated Complexes of Thiosemicarbazones. Synthesis and Crystal Structure of [$Ph_2PC_6H_4CHNNC(S)NHCH_3PtCl$]

  • 유동원;강상욱;고재정;최문근
    • Bulletin of the Korean Chemical Society
    • /
    • 제18권3호
    • /
    • pp.305-310
    • /
    • 1997
  • The synthesis and characterization of the platinum heterocyclic carboxaldehyde thiosemicarbazone complexes [NC5H4CRNNC(S)NHR'PtCl] (R=H, R'=CH3(1); R=CH3, R'=CH3(2); R=CH3, R=H(3)) and diphenylphosphinophenyl carboxaldehyde thiosemicarbazone complexes [Ph2PC6H4CHNNC(S)NHRPtCl] (R=CH3(5); R=iC3H7(6); R=Ph(7)) are described. Compounds 1-3 were prepared by reaction of Pt(SEt2)2Cl2 with 2-acetylpyridine-4-alkylthiosemicarbazone in the presence of NEt3. Compounds 5-7 were prepared using Pt(SEt2)2Cl2 in toluene with diphenylphosphinophenyl carboxaldehyde alkylthiosemicarbazone. The compounds have been characterized by microanalysis, NMR (1H, 13C, 31P) spectroscopy, and single-crystal X-ray diffraction. X-ray single crystal diffraction analysis reveals that compound 5 is a mononuclear platinum compound with P,N,S-coordination mode.

PEMFC 용 Pt 담이 촉매의 Pt 담지비에 따른 성능변화 (Optimization of Platinum amount in Pt/C for PEMFC)

  • 조용훈;조윤환;박현서;성영은
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2006년도 춘계학술대회 논문집
    • /
    • pp.547-548
    • /
    • 2006
  • This study focuses on a determination of amount of Pt in the Pt/C for catalysts of polymer electrolyte membrane fuel cells (PEMFC). PEMFC offer low weight and high power density and being considered fur automotive and stationary power applications. The PEMFC behavior is quite complex is influenced by several factors, including catalysts and structure of electrode and membrane type. Catalyst of electrode is important factor for PEMFC. One of the obstacles preventing polymer electrolyte membrane fuel cells from commercialization is the high cost of noble metals to be used as catalyst, such as platinum. To effectively use these metals, they have to be will dispersed to small particles on conductive carbon supports. The optimal amount of Pt in Pt/C was investigated by using polarization curves in single cell with $H_2/O_2$ operation.

  • PDF