Synthesis of Silica−Gold Nanocomposites and Their Porous Nanoparticles by an In-Situ Approach

Abstract

We demonstrate the one-step synthesis of a silica-gold nanocomposite by simultaneous hydrolysis and reduction of gold chloride. The aminophenyl group was used as a reducing agent, and the trimethoxy silane group acts a precursor for the formation of silica. The porous gold nanoparticles were formed by etching out the silica-gold nanocomposite by hydrofluoric acid. The electron diffraction of porous gold nanoparticles showed that the particle are polycrystalline with FCC structure. The silica-gold nanocomposite exhibited nonlinear current-voltage behavior, and the porous gold nanoparticles displayed linear current-voltage behavior.

A Silica Nanorattle with a Mesoporous Shell: An Ideal Nanoreactor for the Preparation of Tunable Gold Cores

“…Very recently, our group have succeeded in fabricating a kind of unique silica nanorattle (a special hollow nanosphere with mesoporous shell and silica inner core) by selective etching of organic‐inorganic hybrid silica spheres with a three‐layer sandwich structure, using N‐[3‐(trimethoxysilyl) propyl] ethylenediamine (TSD) condensed with tetraethylorthosilane as an etchable layer 20. Notably, after selective etching of middle silica layer, the interior of the silica nanorattles have plenty of residual alkylamino groups, which can act as in situ reducing agent and stabilizer for the growth of metal core 21–26. Because of these unique reactive alkylamino groups inside the hollow spheres, they will facilitate the synthesis of metal core react only inside the middle cavity within one step.…”

Nanostructured Silica/Gold-Cellulose-Bonded Amino-POSS Hybrid Composite via Sol-Gel Process and Its Properties

“…Moreover, the core/shell colloids exhibited the original shape of the Au cores, and a relatively large variation of the size in the hybrid samples. Lastly, when the TEOS concentration is further increased, the silica shell grows thicker to a size between 50 and 100 nm, and a more-uniform and smooth surface is observed [5–7, 13–15]. The TEM micrograph (Fig.…”

“…Therefore, the synthesis protocols of metal-oxide-hybrid composites are already well established in the literature [2, 3] and most of them are multistep metal-nanoparticle processes. The synthesis of the silica/gold hybrid composite materials is achieved using the in situ sol-gel process via the hydrolysis of gold and silica precursors into a cellulose-polyhedral oligomeric silsesquioxanes (POSS) matrix [3–5]. …”

Multifunctional Magnetoplasmonic Nanomaterials and Their Biomedical Applications

“…82 These porous shell-coated functional nanomaterials are useful in many respects, such as catalysis, electronics, and encapsulation of drugs. 83 The porous silica shell does not affect the optical and catalytic properties of Au NPs significantly. On the other hand, it simultaneously acts as a protective layer for magnetic and gold NPs preventing the aggregation and oxidation.…”