In this report we present new insights into the formation mechanism of Ag, Au and AgAu nanoparticles with alcohols, aldehydes and ketones in alkaline medium at room temperature. We selected methanol, ethanol, glycerol, formaldehyde, acetaldehyde and acetone to demonstrate their capability of reducing gold and silver ions under the above-mentioned conditions. We showed that the particles are also formed with potassium tert-butoxide in the absence of hydroxides. Our results strongly suggest that alkoxides, formed from any molecule containing a hydroxyl or a functional group capable of generating them in alkaline medium, are the actual and universal reducing agent of silver and gold ions, in opposition to the currently accepted mechanisms. The universality of the reaction mechanism proposed in this work may impact on the production of noble nanoparticles with simple chemicals normally found in standard laboratories.

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Bimetallic AuAg NPs (NPs) were synthesized via chemical reduction of AuCl 3 and AgNO 3 and fully characterized by several experimental techniques and theoretical calculations. The plasmon absorptions of these NPs were correlated with the most stable particle structure through different simulations, revealing the most stable structure to be consisted of a gold core and a silver shell. This structural motif was then confirmed by HR-TEM coupled with line-scan EDS and molecular dynamics. Finally, the impact of the nanoparticle composition on their catalytic performance for glycerol electro-oxidation was evaluated. The better catalytic performance in terms of the onset potential found for the Au 50 Ag 50 and Au 75 Ag 25 catalysts suggests the existence of a synergistic effect between Au and Ag.