Gold as a novel catalyst in the 21st century: Preparation, working mechanism and applications

Abstract

Gold can be deposited as nanoparticles on a variety of support materials by coprecipitation or depositionprecipitation of Au(OH)3, grafting of organo-gold complexes such as dimethyl-Au(III)-acetylacetonate, mixing of colloidal Au particles, and vacuum deposition. Owing to the moderate adsorption of at least one of reactants (for example, CO) on the edges and corners of Au nanoparticles and to the activation of the counter reactant (for example, O2) at the perimeter interface with the supports, supported Au nanoparticle catalysts exhibit unique and practically useful catalytic properties at relatively low temperature below 473K. They have already been commercially used for deodorizers in rest rooms in Japan and will find growing applications in indoor air quality control, pollutant emission control, production of hydrogen energy carrier, and innovations in chemical processes. Cluster science of Au may also open an exciting area of research showing some magic numbers for dramatic changes in reactivity.

Durable PROX catalyst based on gold nanoparticles and hydrophobic silica

“…5 nm). 10 Another cause of 20 deactivation is the formation of poisoning carbonate-type surface species. 11,12 Most approaches aiming at producing more stable gold catalysts 13 have focused so far on enhancing the thermal stability of gold nanoparticles against sintering 14 by increasing the so- 25 called "strength of gold-support interaction", in e.g.…”

Effects of Support and Synthetic Procedure for Sol-Immobilized Au Nanoparticles

“…However, this technique does not allow obtaining high gold dispersion. In fact, it leads to nanoparticles of size above 30 nm, due to sintering during the heat treatment, promoted by the Cl´ions still present on the sample [2]. Therefore, the gold-based catalysts prepared by this technique have a low catalytic activity [3].…”

Thin films of size-selected Mo clusters: growth modes and structures

“…5 For example, Au nanoparticles smaller than 3-4 nm are active catalysts for various reactions such as the CO oxidation, whereas the bulk counterpart is inert. [5][6][7][8][9] In addition, quantum confinement effects and unique geometric structures dissimilar to the bulk counterparts result in unexpected electronic properties, [8][9][10][11][12][13][14] which make clusters interesting for future nano-electronics.…”