WO2006038045A1 - Synthèse sélective par la dimension de nanoparticules de métal - Google Patents

Synthèse sélective par la dimension de nanoparticules de métal Download PDF

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Publication number
WO2006038045A1
WO2006038045A1 PCT/GR2004/000049 GR2004000049W WO2006038045A1 WO 2006038045 A1 WO2006038045 A1 WO 2006038045A1 GR 2004000049 W GR2004000049 W GR 2004000049W WO 2006038045 A1 WO2006038045 A1 WO 2006038045A1
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WIPO (PCT)
Prior art keywords
pom
process according
silver
metal
reduced
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Application number
PCT/GR2004/000049
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English (en)
Inventor
Anastasia Hiskia
Elias Papaconstantinou
Aristides Troupis - Koukoutsis
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National Center Of Scientific Research 'demokritos'
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Priority to PCT/GR2004/000049 priority Critical patent/WO2006038045A1/fr
Publication of WO2006038045A1 publication Critical patent/WO2006038045A1/fr

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/05—Metallic powder characterised by the size or surface area of the particles
    • B22F1/054—Nanosized particles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
    • B22F2009/245—Reduction reaction in an Ionic Liquid [IL]

Definitions

  • the present invention deals with the size-selective synthesis (preparation) of uniform metal particles and more specifically with the control of the reduction of metal ions in the presence of reduced polyoxometalates (POM), which act as electron donors and possibly also as stabilizers, in order to adjust the size of the obtained particles.
  • POM polyoxometalates
  • metal nanoparticles have been obtained by thermal, photochemical, radiolytic, electrochemical or sonochemical reductive methods, which methods have certain disadvantages. More particularly, almost all these methods are reagents-consuming since two kind of substances are needed: the electron donor in stoichiometric (large) amounts and the stabilizer that stops the growth of the particles to nanometer scale.
  • POM have been proposed as both catalytic electron donors and stabilizers for the synthesis of metal nanoparticles in aqueous solutions using either UV/near-Vis light [A. Troupis, A. Hiskia, E. Papaconstantinou, Angew. Chem. Int. Ed. 2001, 41, 1911] or ⁇ -rays [A V. Gordeev, N.I. Kartashev, B. G. Ershov, High Energy Chem. 2002, 36, 102].
  • the use of POM provides reagents-economy since the addition of a second chemical (stabilizer) is avoided, and besides, only traces of POM are needed (catalytic amounts).
  • stabilizer stabilizer
  • the size of the metal nanoparticles is crucial since it dictates their physical and chemical behavior, such as the ability to accept or release electrons, light absorption, photoredox, photocatalytic, photovoltaic or even bactericidical properties among others. By presenting methods that enable to control the size of these nanoparticles, one could also control the corresponding properties and applications of these particles. It is the object of this invention to provide a process that is able to control the size of the obtained metal nanoparticles at will, using POM as electron donors and as a result define certain properties of the nanoparticles. More particularly, the present invention aims at providing a process with particular advantages, namely a rapid and simple process (simple mixing at room temperature, reagents-economy) by which metal nanoparticles of well- controllable size can be made
  • the invention provides a process for the manufacture of metal nanoparticles in a solution in which a POM (polyoxometalate) is used as catalytic reducing reagent, to induce reduction of a metal cation to form the metal nanoparticles, which process is characterized in that the size of the metal nanoparticles formed is controlled by the selection of POM of appropriate redox potentials, and /or the selection of appropriate concentration of reduced POM, and/or the selection of appropriate concentration of metal ion.
  • POM can also serve as stabilizer.
  • the solution within which the metal nanoparticles are manufactured may be liquid, or ionic liquid.
  • the liquid solution within which the metal nanoparticles are manufactured is aqueous.
  • the metal nanoparticles manufactured are silver nanoparticles.
  • the silver is provided by silver nitrate, silver perchlorate or other soluble silver salt.
  • the metal nanoparticles manufactured are gold, palladium, copper or platinum nanoparticles.
  • the two reactants are gold, palladium, copper or platinum nanoparticles.
  • POM and metal ions are premixed in a POM/organic/metal ion solution (one-pot process).
  • the preparation of the catalytic reducing agent is produced by treatment of a solution containing oxidized POM (or less reduced POM) and oxidizable species by means of exposure to electric current, ⁇ -rays, ultrasound, temperature, UV/near- Visible light, or sunlight.
  • the preparation of the catalytic reducing agent is achieved with the use of oxidizable reagents.
  • the oxidizable reagent is an alcohol, phenol, hydride, chorophenol, cresol, benzene derivative, organohalogenated compounds aliphatic, or a pesticide
  • the process for the formation of silver nanoparticles in a two-step process is as follows:
  • step 1 An aqueous solution of the electron donor-stabilizer is prepared (reduced POM) by illuminating with UV/near-Vis light (according to an embodiment of the invention) a deaerated aqueous solution of oxidized POM / propan-2-ol. Upon illumination, electron transfer from propan-2-ol to POM resulted in the formation of reduced POM, (POM(e-)),
  • step 2 An aqueous silver salt solution such as silver nitrate, silver perchlorate or other water soluble silver salt solutions is prepared, is deaerated and is added to the solution from step 1 or vice versa to produce silver nanoparticles, according to the reaction:
  • the mechanism for the formation of silver nanoparticles, reaction (step) (2) comprises firstly a slow nuclealion step and, then, a fast reductive growth on the already formed nuclei.
  • these two stages and, subsequently, the size of the formed metal particles can be affected via two ways: (i) By changing the rate of metal reduction one can adjust the nucleation process. In general, faster reduction leads to greater number of seeds and, for a fixed initial concentration of silver, the same quantity of silver has to be distributed on greater number of seeds and smaller particles are expected (the "rate rule").
  • the initial amount of silver can affect the extent of the growth process. By increasing silver concentration, for roughly the same number of nuclei, more amount of silver has to be deposited on the same number of seeds and larger particles are expected.
  • the size-selectivity of the process is achieved by varying operational parameters such as the initial concentration of reduced POM, the kind of POM or the extent of reduction of the same POM (which affects the rate of the reaction) or the initial concentration of silver ions (which affects the amount of silver to be deposited).
  • Possible POM are all reducible POM, i.e the Keggin, Dawson, Pryessler, Lindqvist or Anderson structured polyoxometalate anions, or the decatungstate POM.
  • the Keggin and Dawson POM are used.
  • a variety of POMs selected from the two classical types of Keggin and Dawson structrure are used.
  • the following photochemically produced reduced POM were used to reduce Ag + to Ag 0 nanoparticles: the 1-e-reduced Keggin POM SiWi 2 O 40 4" and H 2 W n O 40 6" (SiWj 2 O 40 5" and H 2 Wj 2 O 40 7" ), the 1-e- and 2-e-reduced Dawson phosphotungstate P 2 Wi 8 O 62 6" (P 2 Wi 8 O 62 7" and P 2 Wi 8 O 62 8" ) and the 2-e- and 4-e-reduced Dawson phosphomolybdate P 2 MOi 8 O 62 6" (P 2 MOI 8 OO 2 8" and P 2 MOi 8 O 62 10" ).
  • These reagents exhibit widely-ranged redox potentials dependent on either the nature of POM or the extent
  • Figure 1 shows the structures of the characteristic POM used herein.
  • (A) XM 12 O 40 " . Keggin structure. They are composed of MO 6 octahedra sharing corners and edges. The heteroatom X P, Si or H2 is within the central (shaded) tetrahedron XO 4 .
  • Figure 2 shows the various redox potentials exhibited by polyoxometalate anions and silver ions (Volts vs. NHE).
  • Figure 3 shows a schematic diagram of synthesis and stabilization of Ag nanoparticles in the presence of polyoxometalates.
  • Figure 4 shows the diagram of the variation of the initial rate of SiWnO 40 5" reoxidation with the initial concentration Of SiWi 2 O 40 5' .
  • Figure 5 shows the particle size distribution of the silver particles prepared in solutions of various initial concentrations Of SiWi 2 O 40 5" .
  • Figure 6 shows the UV absorbance of the silver particles prepared in solutions of various initial concentrations of SiW] 2 O 40 5" .
  • Figure 7 shows the diagram of the variation of the UV absorbance peak of the silver particles prepared in solutions of various initial concentrations Of SiWi 2 O 4 O 5" .
  • Figure 8 shows the diagrams of the decrease of reduced POM concentration with reaction time upon addition of silver ions, for various kinds of reduced POM.
  • the inset shows the variation with time of the UV absorbance spectra OfP 2 Wi 8 Oo 2 7" upon addition of silver ions.
  • - Figure 9 shows the influence of the kind of reduced POM on the size distribution and the
  • Figure 10 shows the UV absorbance of the silver particles obtained in the presence of the same POM but with different extent of reduction.
  • Figure 11 shows the diagram of the variation of the initial rate of SiWi 2 O 4 O 5" reoxidation with the initial concentration of Ag + .
  • Figure 12 shows the particle size distribution and the TEM pictures of the silver particles prepared in solutions of various initial concentrations of Ag 1 .
  • Figure 13 shows the UV absorbance of the silver particles prepared in solutions of various initial concentrations of Ag' .
  • Figure 14 shows the diagram of the variation of the UV absorbance peak of the silver particles prepared in solutions of various initial concentrations of Ag + .
  • the preparation of the electron donor solution can be achieved with various ways for different embodiments of the invention; such ways are treatment of a solution containing oxidized POM (or reduced POM) and oxidizable species by means of exposure to electric current, ⁇ -rays, ultrasound, temperature or UV/near- Visible (Vis) light.
  • the photolytic method was used. In all cases electrons were transferred to POM and the reduced POM of characteristic blue color was formed.
  • the reaction media can be a solvent, water or organics, where POM are dissolved (i.e, polar organics such as acetonitrile, acetone, protic solvents such as alcohols e t c.), films where POM are immobilized through i.e. a sol-gel or layer-by-layer technique or ionic liquids, where reduction of POM can also take place.
  • POM polar organics
  • acetone such as acetonitrile
  • protic solvents such as alcohols e t c.
  • films where POM are immobilized through i.e. a sol-gel or layer-by-layer technique or ionic liquids, where reduction of POM can also take place.
  • the metal that was used as target metal was silver.
  • many other metals can also be efficient as target metals, such as gold, palladium, platinum and copper, that are known to be converted to nanoparticles by reduced POM [A. Troupis, A. Hiskia, E.
  • POM from two representative series were used, of the type XMi 2 O 4 O 11" or X 2 MI 8 OG 2 " " , as an example.
  • POM compounds such as the lacunar/ types or other structured POM, can be used.
  • propan-2-ol for the production of reduced POM in the photolytic method is the example presented as an embodiment of this invention.
  • oxidizable reagent i.e., organic pollutants such as phenols, chorophenols, cresols, benzene derivatives, organohalogenated compounds, aliphatics, triazine pesticides e t c [E Papaconstantinou, A. Hiskia, in Polyoxometalate Molecular Science, Borras-Almenar, JJ.
  • the process was also effective at even larger wavelengths, i.e. using sunlight.
  • the two reactants to produce silver nanoparticles the two reactants,
  • Step 1 In order to produce reduced POM 4 ml of an aqueous solution of POM H 4 SiWi 2 O 4 O (m.w. 3096, Aldrich) or K 4 SiWi 2 O 4 O (m.w. 3137, specially synthesized) Na O H 2 Wi 2 O 40 (m.w. 3370, specially synthesized) KeP 2 Wi S O 62 (m.w. 4705, home-made) or (NH 4 ) 6 P2Mo I 8 O 62 (m.w.
  • the concentration of Ag 0 nanoparticles was measured from the increase of the absorbance at ca 420 nm, attributed to the plasmon resonance peak of colloidal silver, taking as absorption coefficient the one calculated at the saturation point of the reaction, when all silver had been reduced.
  • Step 2 silver nanoparticles were obtained by injecting a deaerated aqueous solution of AgNO 3 from Panreac ( ⁇ l of a 3.83xlO "3 M or 0.01 15 M solution were added in order to obtain concentration of silver ions of ca 10 "4 M) to the already prepared POM(e-) solution (4ml).
  • the solutions were mixed, agitated for ca 3 seconds and allowed to stand.
  • the initially blue solution turned green and finally yellow within time that spanned from seconds to hours depending on the POM used.
  • Silver nanoparticles were formed according to reaction (2).
  • the obtained silver nanoparticles were characterized using Transmission Electron Microscopy. The corresponding images were obtained using a Philips 20OkV microscope, while the samples were prepared by placing microdrops of colloid solution on a Fprmvar/Carbon coated copper grid. The subsequent analysis for the size-distribution of the particles was based on the counting of ca 150 particles.
  • the initial rate of POM(e-) reoxidation was calculated by the slope of the curve of the concentration of POM(e-) vs. time of the reaction with silver ions, for conversion less than 30 %
  • control of the size of the nanoparticles was achieved by changing either the reaction rate [by variation of POM(e-) initial concentration, kind of POM or extent of reduction of the same POM] or the amount of silver ions. , More particularly:
  • K 6 P 2 Wi 8 O 62 (1 2x10 4 M) and propan-2-ol (2.0 M) were photolyzed to form the 1-e- reduced POM P 2 Wi 8 O 62 7" at 1.OxIO "4 M.
  • Another 4 ml of the K 6 P 2 W 18 O 62 (1.2xlO "4 M) and propan-2-ol (2.0 M) solution were deaerated and illuminated for further time to form the 2-

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Abstract

L'invention concerne la préparation sélective par la dimension de nanoparticules de métal dans des solutions de polyoxométalates (POM). Selon ce procédé, des POM réduits peuvent agir comme donneurs d'électrons catalytiques et éventuellement également comme stabilisateurs qui limitent les dimensions des particules à l'échelle nanoscopique. La dimension des particules formées est régulée par le choix du type approprié de POM réduits, et/ou des concentrations adéquates de POM réduits, et/ou des concentrations adéquates d'ions métalliques.
PCT/GR2004/000049 2004-10-05 2004-10-05 Synthèse sélective par la dimension de nanoparticules de métal WO2006038045A1 (fr)

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010021600A1 (fr) * 2008-08-22 2010-02-25 Agency For Science, Technology And Research Procédés et compositions comprenant des polyoxométalates
CN102304152A (zh) * 2011-04-20 2012-01-04 南开大学 一种含钼多金属氧酸盐的金刚烷杂化化合物及其制备方法
CN104174869A (zh) * 2014-08-25 2014-12-03 常州大学 一种超长制备银纳米线的方法
CN104308184A (zh) * 2014-10-24 2015-01-28 武汉理工大学 一种可见光制备Au-Ag核壳纳米粒子的方法
CN106825601A (zh) * 2016-12-30 2017-06-13 西安交通大学青岛研究院 一种银纳米线的制备方法
CN107744823A (zh) * 2017-09-26 2018-03-02 浙江工商大学 一种多金属氧酸盐基复合可见光催化剂的制备方法
US9993812B2 (en) 2012-04-17 2018-06-12 Momentive Pereformance Materials Inc. High activity catalyst for hydrosilylation reactions and methods of making the same
CN108273990A (zh) * 2018-02-02 2018-07-13 东莞华晶粉末冶金有限公司 一种钛合金蜡基喂料及其制备方法
CN108311689A (zh) * 2017-01-17 2018-07-24 东莞华晶粉末冶金有限公司 粉末注射成型喂料及其制备方法和应用
CN113145170A (zh) * 2020-12-31 2021-07-23 东北电力大学 一种可见光全吸收饱和型Keggin结构磷钼酸盐复合材料的制备方法
CN115805088A (zh) * 2022-08-15 2023-03-17 河南师范大学 一种基于银簇和Nb/W混金属多酸光催化剂及其制备方法和应用

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GORDEEV ET AL.: "Metal Nanoparticles with PW11O397- and P2W17O6110- Heteropoly Anions as Stabilizing Agents: Radiation-Chemical Preparation and Properties", HIGH ENERGY CHEMISTRY, vol. 36, no. 2, 2002, pages 75 - 79, XP009041119 *
TROUPIS A ET AL: "Photocatalytic reduction - Recovery of silver using polyoxometalates", APPL. CATAL. B ENVIRON.; APPLIED CATALYSIS B: ENVIRONMENTAL MAY 28 2003, vol. 42, no. 3, 28 May 2003 (2003-05-28), pages 305 - 315, XP002309322 *
TROUPIS ET AL.: "Synthesis of Metal Nanoparticles by Using Polyoxometalates as Photocatalysts and Stabilizers", ANGEW. CHEM. INT. ED., vol. 41, no. 11, 2002, GERMANY, pages 1911 - 1914, XP002309321 *

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012500896A (ja) * 2008-08-22 2012-01-12 エージェンシー フォー サイエンス， テクノロジー アンド リサーチ ポリオキソメタレートを含む方法および組成物
WO2010021600A1 (fr) * 2008-08-22 2010-02-25 Agency For Science, Technology And Research Procédés et compositions comprenant des polyoxométalates
CN102304152A (zh) * 2011-04-20 2012-01-04 南开大学 一种含钼多金属氧酸盐的金刚烷杂化化合物及其制备方法
CN102304152B (zh) * 2011-04-20 2013-09-18 南开大学 一种含钼多金属氧酸盐的金刚烷杂化化合物及其制备方法
US9993812B2 (en) 2012-04-17 2018-06-12 Momentive Pereformance Materials Inc. High activity catalyst for hydrosilylation reactions and methods of making the same
CN104174869A (zh) * 2014-08-25 2014-12-03 常州大学 一种超长制备银纳米线的方法
CN104174869B (zh) * 2014-08-25 2016-08-24 常州大学 一种制备超长银纳米线的方法
CN104308184A (zh) * 2014-10-24 2015-01-28 武汉理工大学 一种可见光制备Au-Ag核壳纳米粒子的方法
CN106825601A (zh) * 2016-12-30 2017-06-13 西安交通大学青岛研究院 一种银纳米线的制备方法
CN108311689B (zh) * 2017-01-17 2020-04-03 东莞华晶粉末冶金有限公司 粉末注射成型喂料及其制备方法和应用
CN108311689A (zh) * 2017-01-17 2018-07-24 东莞华晶粉末冶金有限公司 粉末注射成型喂料及其制备方法和应用
CN107744823A (zh) * 2017-09-26 2018-03-02 浙江工商大学 一种多金属氧酸盐基复合可见光催化剂的制备方法
CN107744823B (zh) * 2017-09-26 2020-06-16 浙江工商大学 一种多金属氧酸盐基复合可见光催化剂的制备方法
CN108273990A (zh) * 2018-02-02 2018-07-13 东莞华晶粉末冶金有限公司 一种钛合金蜡基喂料及其制备方法
CN113145170A (zh) * 2020-12-31 2021-07-23 东北电力大学 一种可见光全吸收饱和型Keggin结构磷钼酸盐复合材料的制备方法
CN115805088A (zh) * 2022-08-15 2023-03-17 河南师范大学 一种基于银簇和Nb/W混金属多酸光催化剂及其制备方法和应用

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