In situ XAFS studies of Au particle formation by photoreduction in polymer solutions

被引：55

作者：

Department of Health Science and Clothing Environment, Faculty of Human Life and Environment, Nara Women's University, Nara 630-8506, Japan ^{[1
]}

不详 ^{[2
]}

机构：

[1] Department of Health Science and Clothing Environment, Faculty of Human Life and Environment, Nara Women's University

[2] Department of Energy and Material Sciences, Faculty of Engineering Sciences, Kyushu University, Kasuga

来源：

Langmuir | 2007年 / 12卷 / 6536-6543期

关键词：

50;

D O I：

10.1021/la0701071

中图分类号：

学科分类号：

摘要：

Formation mechanisms of metal particles (gold (Au) particles) in an aqueous ethanol solution of HAuCl4 with poly(N-vinyl-2-pyrrolidone) (PVP) by the photoreduction method were investigated by UV-vis, transmission electron microscopy (TEM), and in situ and ex situ X-ray absorption fine structure (XAFS) analysis. The average diameters of the dilute and concentrated Au particles in PVP solution are estimated from TEM to be 106 Å and 925 Å, respectively. XAFS analysis was carried out to elucidate the reduction process of AuCl4- ionic species to metallic Au particles for the Au-L3 edge of the colloidal dispersions of the concentrated Au solutions. In the photoreduction process, the reduction of AuCl2 - species to Au0 atoms is a slower process than that of AuCl4- to AuCl2-, and the reduction of AuCl2- to Au0 atoms and the association of Au0 atoms to form seed Au particles (particle diameter between 5.5 and 30 Å) concurrently proceeds in the short-duration photoirradiation. In addition, in the long-duration photoirradiation, the slow progression of Au particle growth occurs with the association of Au0-Au0 metallic bonds, resulting in the formation of larger Au particles (particle diameter larger than 500 Å). © 2007 American Chemical Society.

引用

页码：6536 / 6543

页数：7

共 48 条

[1]

Davis S.C., Klabunde K.J., Chem. Rev, 82, (1982)

[2]

St. John J., Coffer J.L., Chen Y., Pinizzotto R.F., J. Am. Chem. Soc, 121, (1999)

[3]

Templeton A.C., Pietron J.J., Murray R.W., Mulvaney, P. J. Phys. Chem. B, 104, (2000)

[4]

Schmid G., Chem. Rev, 92, (1992)

[5]

Henglein A., Chem. Rev, 89, (1989)

[6]

Lewis L.N., Chem. Rev, 93, (1993)

[7]

Pileni M.P., Langmuir, 13, (1997)

[8]

D'Souza L., Sampath S., Langmuir, 16, (2000)

[9]

Torigoe K., Esumi K., Langmuir, 8, (1992)

[10]

Tamai H., Sakurai H., Hirota Y., Nishiyama F., Yasuda H., J. Appl. Polym. Sci, 56, (1995)

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