Preparation and optical absorption of gold nanoparticles within pores of mesoporous silica

Abstract Nanoscale gold particles dispersed within pores of mesoporous silica were synthesized by soaking and thermal reduction of chloroauric acid (HAuCl 4 ) in H 2 atmosphere at 973 K for 1 h. This new material was characterized by X-ray diffraction, transmission electron microscopy, and Brunauer–Emmett–Teller (BET) techniques. It is shown that gold nanoparticles are isolated from each other and uniformly dispersed inside the pores of silica, which were less than 4 nm in diameter. It is found that in optical absorption spectra, the Mie resonance frequency of gold particles shows a significant red-shift with decreasing Au particle size. This red-shift phenomenon is qualitatively explained in terms of the interface interaction between the pore walls of porous silica and Au particles within the pores.

[1]  M. Broyer,et al.  Optical properties of gold clusters in the size range 2-4 nm , 1998 .

[2]  W. A. Phillips,et al.  Electrical and optical properties of amorphous indium oxide , 1990 .

[3]  J. Kleinberg,et al.  Treatise on inorganic chemistry , 1956 .

[4]  U. Kreibig,et al.  OPTICAL ABSORPTION OF SMALL METALLIC PARTICLES , 1985 .

[5]  R. Doremus Optical Properties of Small Gold Particles , 1964 .

[6]  C. Weiping,et al.  Synthesis and structural and optical properties of mesoporous silica containing silver nanoparticles , 1997 .

[7]  A. Trotman‐Dickenson,et al.  ‘Comprehensive’ Inorganic Chemistry , 1958, Nature.

[8]  T. Kundu,et al.  Nanocomposite films of lead zirconate titanate and metallic nickel by sol-gel route , 1995 .

[9]  Vollmer,et al.  Width of cluster plasmon resonances: Bulk dielectric functions and chemical interface damping. , 1993, Physical review. B, Condensed matter.

[10]  Michael Vollmer,et al.  Optical properties of metal clusters , 1995 .

[11]  P. Judeinstein,et al.  Polymetalates based organic-inorganic nanocomposites , 1994 .

[12]  T. W. Żerda,et al.  Porous silica glasses doped with quantum-confined cadmium selenide , 1992 .

[13]  Weiping Cai,et al.  Reversible transition between transparency and opacity for the porous silica host dispersed with silver nanometer particles within its pores , 1996 .

[14]  E. Teller,et al.  ADSORPTION OF GASES IN MULTIMOLECULAR LAYERS , 1938 .

[15]  V. Kresin,et al.  Collective resonances in silver clusters: Role of d electrons and the polarization-free surface layer. , 1995, Physical review. B, Condensed matter.

[16]  Fedrigo,et al.  Collective dipole oscillations in small silver clusters embedded in rare-gas matrices. , 1993, Physical review. B, Condensed matter.

[17]  Z. Kam,et al.  Absorption and Scattering of Light by Small Particles , 1998 .

[18]  Youichi Kurokawa,et al.  Linear and nonlinear optical properties of sol-gel-derived Au nanometer-particle-doped alumina , 1997 .

[19]  S. J. Gregg,et al.  Adsorption Surface Area and Porosity , 1967 .

[20]  O. Puglisi X-ray photoelectron spectroscopy of AuSi ion-beam-mixed films , 1985 .

[21]  A. Gabel,et al.  Ultrafast carrier and grating lifetimes in semiconductor‐doped glasses , 1985 .