Controlling structure and composition in double-heterojunction nanorods for high quantum yield and tunable color

Nanoparticle synthesis;Quantum dots;Double-heterojunction nanorods

Drake, Gryphon Aubrey ; Shim ; Moonsub

关键词: Nanoparticle synthesis;    Quantum dots;    Double-heterojunction nanorods;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/98310/DRAKE-THESIS-2017.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Limitations of colloidal semiconductor double-heterojunction nanorods reported thus far are low photoluminescence quantum yield, low color purity owing to wide size distribution, and emission over a narrow range of energies in the visible spectrum. Here we report alterations to the synthetic route which result in a narrow size and morphological distribution of CdS nanorod seeds tunable over a range of lengths from 10 – 50 nm and quantum-confined bandgaps between 2.62 – 2.78 eV. Variously sized CdS seeds are then used to investigate the effects of the rate of Zn-Oleate etching and of the rate and amount of ZnSe growth on DHNR morphology and optical properties. Structure and composition are investigated by TEM. Each are shown to depend sensitively on the synthetic route. We ultimately demonstrate DHNR with emission wavelength tunable between 2.04 - 2.16 eV, photoluminescence quantum yield up to 68%, and full width at half maximum photoluminescence as low as 84 meV.