One-step aqueous synthesis of highly luminescent hydrophilic AgInZnS quantum dots

Abstract

We report a one-step method to directly synthesize highly luminescent AgInZnS quantum dots (AIZS QDs) in aqueous media by using 3-mercaptopropionic acid as stabilizer with the quantum yield (QY) up to 41.2%, which is the highest for these hydrophilic QDs to the best of our knowledge. The aqueous-dispersible AIZS QDs are quasi-spherical and ~ 3 nm in diameter, possessing average fluorescence lifetime as long as 262.55 ns and exhibiting excellent stability in water. Simply by tailoring the stoichiometric ratio of Ag or Zn, the emission colors could be easily tuned from green to red, which also exhibits great potential in biological labelling and optoelectronic devices.