The size-controllable, one-step synthesis and characterization of gold nanoparticles protected by synthetic humic substances

Abstract

In this paper we demonstrate the use of synthetic humic substances (HSs) in the synthesis of gold nanoparticles in which the unprecedented control of particle size and shape is achieved by varying the experimental conditions. In this reaction, the synthetic HSs are used as a reductive and protective reagent. A number synthetic HSs from different fenol precursors are tested. The nanoparticles formation processes were monitored by UV–visible spectroscopy, and the results were analyzed by transmission electron microscopy and X-ray diffraction. The preference of synthetic HSs over natural HSs is determined by a standardization problem resolution due to the strict control of the HSs formation conditions that expand the areas of application of the gold nanoparticles fabricated with such technique. These nanodispersions are aggregately stable for more than one year. The possible formation mechanism of primary gold nanoclusters is proposed.