Silver and gold nanoparticles in silica matrices: synthesis, properties, and application

Abstract

Methods of synthesis, optical characteristics, morphology, and catalytic and bactericidal characteristics of composite materials based on silica (films and powders) containing nanoparticles of silver, gold, and their binary compounds with alloy or core-shell structure are examined. The photochemical reduction of Au 3+ and Ag + with a photocatalyst (a film of SiO 2 with adsorbed benzophenone) makes it possible to generate stable nanoparticles of gold and silver in solutions for subsequent introduction into adsorbents and catalysts. Examples of the use of nanosized composites in catalysis and in microbiological experiments are presented.

Photochemical Synthesis of Gold and Silver Nanoparticles—A Review

“…Moreover, it diminishes or eliminates the generation of waste and hazardous by-products [ 42 , 48 , 49 ]. Depending on the starting material, the photoinduced synthesis can be classified as photophysical if a bulk material is downsized to nanomaterials (top–down pathway) or photochemical when atoms and molecules are assembled to build up the nanoparticles (bottom–up pathway) [ 42 , 49 , 50 , 51 , 52 ], as indicated in Figure 1 . The photochemical synthesis method has comparative advantages, such as rigorous irradiation control, room temperature operation, simple and inexpensive equipment, and does not require highly skilled personnel [ 40 , 53 , 54 , 55 , 56 ].…”

Photo-induced generation of size controlled Au nanoparticles on pure siliceous ordered mesoporous silica for catalytic applications

“…Most of the methods used to generate gold nanoparticles are bottom-up methods, because the control of their state and shape is quite easy [16][17][18][19][20][21][22][23][24][25][26][27]. The different bottom-up methods, which can be distinguished from the reduction methods used for the generation of gold nanoparticles, are divided into different categories: the first one is based on chemical approaches (use of chemical reducing agents), the second one involves physical approaches (use of ultrasonic methods, electrochemistry, ionizing radiations) and another one is based on photo-assisted methods (UV irradiation, laser photolysis).…”

“…The disadvantage of chemical approaches is the presence of impurities in the reagents. Some approaches based on high temperature thermal reduction in air for a few hours have been also reported for the formation of gold nanoparticles [26,27]. However, these thermal strategies are much less used than those based on chemical reduction because of the propensity of nanoparticles to aggregate significantly at high temperature.…”

Spin Coated Plasmonic Nanoparticle Interfaces for Photocurrent Enhancement in Thin Film Si Solar Cells

“…However, this method creates typically a limited range of particle sizes and shapes. Conversely, synthesis of plasmonic NPs using colloid chemistry techniques offers much greater control over particle size, shape, mono-dispersity, and passivating shell layers [16], [17]. Subsequently, manufacturing of plasmonic interfaces from NP suspensions using wet chemistry methods could offer robust and controllable means for tailoring plasmonic interfaces with desired optical properties [18], [19].…”