Growth of colloidal PbS nanosheets and the enhancement of their photoluminescence.

Dual photoluminescence peaks observed during the synthesis of colloidal PbS nanosheets reveal their growth mechanism - two-dimensional attachments of the quantum dots. Well-grown nanosheets show the photoluminescence linewidth of 95 meV at room temperature. Aged nanosheets in toluene have enhanced photoluminescence with intensity improved by an order of magnitude.