Synthesis of AgInS2 QDs in droplet microreactors: Online fluorescence regulating through temperature control

Abstract

For the synthesis of AgInS2 quantum dots (QDs), a suitable temperature is extremely important for control of the size, shape and fluorescence properties of QDs. Most of synthesis methods for AgInS2 QDs are based on batch reactors, which bring uneven distribution of temperature, affecting their fluorescence properties and size uniformity. Here we designed a droplet microreactor with a temperature-controllable region, and successfully synthesized water-soluble AgInS2 QDs. By accurately controlling temperature, we also studied how the reaction temperature affected the fluorescence properties of AgInS2 QDs. The results showed that with the increasing of reaction temperature, the QDs size increased and the fluorescence peak constantly red-shifted along with enhanced fluorescence intensity. Based on the droplet microreactor, we could achieve more appropriate reaction condition to synthesize AgInS2 QDs with higher fluorescence quantum yield (QY) and intensity.