SYNTHESIS AND CHARACTERIZATION OF COLLOIDAL METAL AND SEMICONDUCTOR PARTICLES PREPARED IN MICROEMULSIONS

被引:61
作者
CLINT, JH
COLLINS, IR
WILLIAMS, JA
ROBINSON, BH
TOWEY, TF
CAJEAN, P
KHANLODHI, A
机构
[1] UNIV E ANGLIA, SCH CHEM SCI, NORWICH NR4 7TJ, NORFOLK, ENGLAND
[2] UNILEVER RES LTD, PORT SUNLIGHT LAB, BEBINGTON L63 3JW, CHESHIRE, ENGLAND
来源
FARADAY DISCUSSIONS | 1993年 / 95卷
关键词
D O I
10.1039/fd9939500219
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The preparation of colloidal particles of platinum 'in situ' in water-in-oil microemulsions formed by the aerosol-OT (AOT)-water-heptane system and the hexadecyltrimethylammonium bromide (CTA B)-water-heptane-chloroform system is described. In both systems, particle growth is controlled and particle sizes of the order of a nm or so are obtained. In the AOT system, there is only a weak correlation between the particle size and droplet size. To obtain further insight into the mechanism of particle growth, the kinetics of the process were investigated. Nucleation particles (Pt-o) are produced in an initial step by the reduction of PtCl62- (Pt-IV) using hydrazine as reducing agent. The kinetics of this stage were found to be erratic and this was attributed to a reaction of AOT with hydrazine. This also had the effect of flocculating the microemulsion system (forming networks) which drastically perturbed the size measurements made using the sedimentation velocity (ultracentrifuge) method. Fractal growth was also indicated by light-scattering measurements. In CTAB microemulsions, the hpdrazine was stable but a gradual replacement of the platinum complex ion (PtCl62-)-Cl-IV by Br- was indicated. The kinetics of nucleation were affected by internal partitioning within droplets, but for both systems small particles in the 1-2 nm radius size range were obtained. The sizes were dependent on droplet size but again the particle sizes did not equate with the droplet sizes. The catalytic ability of these particles in microemulsions has been demonstrated.
引用
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页码:219 / 233
页数:15
相关论文
共 40 条
  • [1] AIKA K, 1976, J RES I CAT HOKKAIDO, V24, P55
  • [2] BOUTONNET M, 1986, APPL CATAL, V20, P163
  • [3] THE PREPARATION OF MONODISPERSE COLLOIDAL METAL PARTICLES FROM MICRO-EMULSIONS
    BOUTONNET, M
    KIZLING, J
    STENIUS, P
    [J]. COLLOIDS AND SURFACES, 1982, 5 (03): : 209 - 225
  • [4] THE EFFECT OF ALKANES ON THE FORMATION OF ULTRAFINE SILVER BROMIDE PARTICLES IN IONIC W/O MICROEMULSIONS
    CHEW, CH
    GAN, LM
    SHAH, DO
    [J]. JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY, 1990, 11 (06) : 593 - 609
  • [5] DYNAMICS OF LIGHT-INDUCED WATER CLEAVAGE IN COLLOIDAL SYSTEMS
    DUONGHONG, D
    BORGARELLO, E
    GRATZEL, M
    [J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1981, 103 (16) : 4685 - 4690
  • [6] EADON DG, 1991, J CHEM SOC F1, V87, P3881
  • [7] EASTOE J, 1990, THESIS UEA
  • [8] PREPARATION OF BIMETALLIC PD-PT COLLOIDS IN ORGANIC-SOLVENT BY SOLVENT-EXTRACTION REDUCTION
    ESUMI, K
    SHIRATORI, M
    ISHIZUKA, H
    TANO, T
    TORIGOE, K
    MEGURO, K
    [J]. LANGMUIR, 1991, 7 (03) : 457 - 459
  • [9] PHOTOCHEMISTRY OF COLLOIDAL SEMICONDUCTORS .10. EXCLUSION CHROMATOGRAPHY AND STOP FLOW EXPERIMENTS ON THE FORMATION OF EXTREMELY SMALL CDS PARTICLES
    FISCHER, CH
    WELLER, H
    FOJTIK, A
    LUMEPEREIRA, C
    JANATA, E
    HENGLEIN, A
    [J]. BERICHTE DER BUNSEN-GESELLSCHAFT-PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 1986, 90 (01): : 46 - 49
  • [10] STRUCTURAL STUDY OF MICROEMULSIONS OF GLYCEROL STABILIZED BY CETYLTRIMETHYLAMMONIUM BROMIDE DISPERSED IN HEPTANE + CHLOROFORM MIXTURES
    FLETCHER, PDI
    GALAL, MF
    ROBINSON, BH
    [J]. JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS I, 1985, 81 : 2053 - 2065