In-Situ Incorporation of Gold Nanoparticles of Desired Sizes into Three-Dimensional Macroporous Matrixes

Abstract

We present here a facile route to the incorporation of gold nanoparticles (GNPs) with desired sizes into three-dimensionally ordered macroporous (3DOM) matrixes. Our route combined the first attachment of small GNPs to the silica colloidal crystal templates as precursors and their subsequent controlled growth by the in-situ chemical reduction method. The desired enlargement of GNPs was acquired via their alternating and repeated exposure to solutions of auric salts and reducing agent NH(3)OH. Such gold-decorated silica templates were also converted into self-sustained polystyrene (PS) macroporous films with GNPs embedded in their wall structures. The growth of gold seeds can be easily followed by their UV-vis absorbance spectra. The route provides an alternative way to incorporate GNPs with predetermined sizes into 3DOM matrixes without destroying their ordered structures. A highlight of our approach is that it obviates the need for the preformation of various-sized GNPs, which is an indispensable step in many other approaches.

Three-Phase Co-assembly: In Situ Incorporation of Nanoparticles into Tunable, Highly Ordered, Porous Silica Films

“…The incorporation of metal nanoparticles into inverse opals has recently attracted particular attention in the literature. 8,[10][11][12][13][14][15][16][17][18][19][20][21] The high surface area and photonic properties of inverse opals coupled with the plasmonic 22,23 or catalytic 24 properties of metal nanoparticles greatly expand the possible applications of these materials as catalysts, 8 sensors, 14,15 photonic structures, [15][16][17][18] and in Surface-Enhanced Raman Spectroscopy (SERS). 20 In most prior investigations, however, inverse opal structures were fabricated by multi-step processes involving assembly of colloidal crystals as sacrificial templates, then infiltrating the structure with a matrix material, such as an appropriate hydrolyzable alkoxide solgel precursor, allowing gelation to take place, and, subsequently, removing the colloidal template by dissolution or thermal decomposition.…”

Homogeneous coating of photonic macroporous oxides with inorganic nanocrystals

“…Quantitative nanoparticle coverage was probed using photonic macroporous oxide supports. Composites of nanocrystals of TiO 2 , Fe 3 O 4 or CdS dispersed onto macroporous SiO 2 or ZrO 2 all show a predictable linear shift in the photonic stop band position.…”

“…To control nanoparticle dispersion, surface treatments such as silylation have been developed for porous ceramic monoliths that increase the nanoparticle to substrate hydrophobic interaction, 4 and specific bonding interactions such as disulphide linkages to anchor Au nanoparticles. 3b, 5 All these studies are limited to metal nanoparticles supported on monoliths for principally catalytic and analytical applications and typically use metal loadings < 5 wt%.…”

Plasmonic biosensors and nanoprobes based on gold nanoshells

“…The 3D SiO 2 arrays were then converted into self-supporting polystyrene (PS) macroporous films, which are depicted in Figure 5 [30,31]. To make 3D GNSs arrays play greater roles, such as an active SERS substrate, we recently developed self-assembled 3D ordered GNSs arrays by improved experimental methods [32].…”