Figure 2.

Optical properties of CdSe QDs (dispersed in chloroform) can be tuned by the size of the particle, known as the quantum size effect. (A) Fluorescence image of monodisperse QDs after ultraviolet illumination, ranging in size from 2.2 −7.3 nm. (B) Fluorescence spectra of the same four QD samples. Narrow and symmetric emission bands are observed, indicating low variance in particle size. (C) Absorption spectra of the same four QD samples. Broad absorption spectra are observed, enabling a wide range for excitation of the QDs. Adapted from [9] with permission from Elsevier.