A facile synthesis of highly efficient and widely emission tunable quintuple CuZnGaSSe quantum dots

Due to their unique optical properties, I-III-VI alloyed quantum dots (QDs) have attracted significant attention. By cationic alloying and composition adjusting, quaternary and quintuple alloyed QDs could be synthesized and the optical properties could be further investigated by adjusting the synthesis parameters. In this study, we synthesized CuZnGaSSe (CZGSSe) QDs using a one-pot method and the photoluminescence quantum yield (PL QY) could reach 72.2%. The effects of the capping ligands, the halogen ions in Zn precursors and the reaction temperatures were explored and the growth mechanism of the CZGSSe QDs was discussed. Finally, by adjusting the S/Se ratio and Cu/Ga ratio, the prepared QDs exhibited tunable emission wavelengths ranging from 469 nm to 599 nm. This study is of significance for researching the growth sequence and guiding the synthesis of efficient quintuple QDs.