Highly luminescent water-soluble AgInS2/ZnS quantum dots-hydrogel composites for warm white LEDs

Ternary Ⅰ-Ⅲ-Ⅵ quantum dots (QDs) have become promising color-conversion materials for warm white light-emitting diodes (WLEDs) because of their broad emission, large stokes shift, high luminescence and low-toxicity. In this work, AgInS 2 /ZnS (AIS/ZnS) core/shell QDs were synthesized via a facile microwave-assisted aqueous method. The PL emission can be tuned from 540 to 622 nm by varying the Ag/In ratio and the maximum quantum yield can reach 58.27%. Flexible luminescent films were obtained by embedding AIS/ZnS QDs in polyacrylamide hydrogel, which were combined with blue InGaN chips to fabricate remote-type warm WLEDs. The as-prepared LEDs exhibit a relatively high color rendering index (CRI) of 87.5 and a correlated color temperature (CCT) of 3669 K, indicating that water-soluble AIS/ZnS QDs are competitive color-conversion materials for warm WLEDs.