Cation exchange of aqueous CuInS2 quantum dots

Abstract

Chalcopyrite copper indium disulfide (CIS) QDs have been of recent interest due to their non-toxicity. Although publications on CIS QDs are becoming more common, the majority of synthesis involves long chained insulating ligands, which are only soluble in non-polar solvents. Recent works have explored the tunable properties of CIS QDs by means of cation exchange with ZnS. Despite this, their tunable properties have been limited to use in organic solvents. This may be due to the cation exchange not being completely understood. For the first time, we present a controllable cation exchange for water soluble, tunable CIS QDs. We also show the partial exchange of indium for zinc, which is shown to provide these QDs with unique optical properties.