Synthesis of CdSe/ZnS and CdTe/ZnS Quantum Dots: Refined Digestive Ripening

Figure 6

Shell coating on digestively ripened CdSe QDs. The broad emission band from 625–700 nm wavelength in core CdSe QDs is due to surface traps. But upon ZnS shell growth, the emission due to surface traps was reduced and simultaneously enhanced PL can be seen. The PL shift from 540 nm to 545 nm and then to 555 nm indicates the growth of shell material on the CdSe Core.