A tri-n-octylphosphine-assisted successive ionic layer adsorption and reaction method to synthesize multilayered core-shell CdSe-ZnS quantum dots with extremely high quantum yield.

Multilayered ZnS shells are coated on a CdSe quantum dot (QD) core by a tri-n-octylphosphine-assisted successive ionic layer adsorption and reaction (TOP-SILAR) method. Notably, the quantum yield (QY) of obtained core-shell CdSe/ZnS QDs can reach up to 95% after coating with a 3-monolayered ZnS shell, and is maintained even after coating with a 6-monolayered ZnS shell, breaking through the bottleneck of low QY at high coverage of the shell.