Fluorescence Energy Transfer from Doped to Undoped Quantum Dots

We report here the fluorescence energy transfer between two types of inorganic semiconductor nanocrystals: one is doped (d-dots) with optically active transition metal ion and other one is the undoped quantum dots (q-dots). While the two types of undoped quantum dots do not show significant energy transfer, the doped quantum dots under similar conditions show efficient energy transfer to the undoped one. The difference in the lifetime makes the doped quantum dots as donor for quantum dots. Exploring Cu-doped and Mn-doped d-dots as donor with the suitable size of CdSe q-dots as acceptor, we report here a detailed study of d-dot to q-dot energy transfer and investigate the possible mechanism

Doping Transition Metal (Mn or Cu) Ions in Semiconductor Nanocrystals

Following growth doping strategy and using dopant oxides nanocrystals as dopant sources, we report here two different transition-metal ions doped in a variety of group II−VI semiconductor nanocrystals. Using manganese oxide and copper oxide nanocrystals as corresponding dopant sources, intense photoluminescence emission over a wide range of wavelength has been observed for different host nanocrystals. Interestingly, this single doping strategy is successful in providing such highly emissive nanocrystals considered here, in contrast with the literature reports that would suggest synthesis strategies to be highly specific to the particular dopant, host, or both. We investigate and discuss the possible mechanism of the doping process, supporting the migration of dopant ions from dopant oxide nanocrystals to host nanocrystals as the most likely scenario