Preparation and Catalytic Performance of Highly Stable Silica-Coated Gold Nanorods Supported on Alumina

Abstract

Shape-controlled metal nanocrystals such as nanorods are attractive because of their potential novel catalytic properties. It is important to improve the stability of the shape-controlled nanocrystals to be applied as nanocatalysts. In this study, α-Al2O3-supported Au nanorods (AuNR/α-Al2O3) and silica-coated α-Al2O3-supported Au nanorods (SiO2/AuNR/α-Al2O3) were prepared as alcohol oxidation catalysts for the transformation of 1-phenylethyl alcohol to acetophenone. The formation rate of acetophenone over AuNR/α-Al2O3 is higher than that over α-Al2O3-supported spherical Au nanoparticles obtained by calcining AuNR/α-Al2O3. In addition, SiO2/AuNR/α-Al2O3 exhibits higher catalytic performance and thermal stability than those of AuNR/α-Al2O3 in alcohol oxidation.

Nanoarchitectonics and Catalytic Performance of Au-Pd Nanoflowers Supported on Fe₂O₃

“…The Al 2 O 3 -and Fe 2 O 3 -supported NFs are purple and black, respectively. Generally, anisotropic nanocrystals transform into spherical NPs by calcination because spherical NCs have a smaller surface area per unit volume [17][18][19]23) . In addition, supported spherical NPs were synthesized by heating the supported Al 2 O 3 spherical NFs in air at 230℃ for 1 h to compare their catalytic activity with that of supported NFs.…”

Catalytic activity of gold nanoparticles protected by quaternary ammonium salt-based gemini surfactants with different spacer structures

“…It was first reported by Esumi et al [11][12][13][14][15][16][17] and Pal et al 18 that gold nanoparticles participate in the reduction reaction of p-nitrophenol (p-NP) and the radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH). Gold nanostructures protected by silicon dioxide, 19 dendrimers, 11,12,15 and biopolymers 13 have been shown to exhibit high catalytic and radical scavenging activities. Investigating the effect of new types of surfactants on the catalytic activities of gold nanoparticles is therefore of great interest.…”