Size-controlled synthesis of silver nanoparticles from silver mirror reaction in toluene

Size-controlled silver nanoparticles (Ag NPs) with a size of 2–15 nm have been synthesised from silver (Ag) mirror reaction in toluene , which refers to reduction of Ag precursor (Ag–dodecylamine complexes solution) by acetaldehyde (CH3CHO) in the presence of oleic acid (OLA). In this synthesis, the size of Ag NPs was finely tuned by just varying the Ag precursor concentrations (c Ag). The addition of OLA can play an important role in stabilising the emerging Ag nuclei. With the OLA/Ag molar ratio at 3:1, the adsorption layer of enough OLA on the surface of the emerging Ag nuclei prevented the direct contact between Ag+ ions and Ag nuclei, and Ag nuclei grew up to their final size by the aggregation mechanism.