SHAO Cong, LIU Xue-yan, ZHAO Jia-long. Effect of Mercaptopropionic Acid Molecules on Electron Transfer from CdSe Core/Shell Quantum Dots to ZnO Nanocrystal Films[J]. 发光学报, 2012,33(1): 26-31
SHAO Cong, LIU Xue-yan, ZHAO Jia-long. Effect of Mercaptopropionic Acid Molecules on Electron Transfer from CdSe Core/Shell Quantum Dots to ZnO Nanocrystal Films[J]. 发光学报, 2012,33(1): 26-31 DOI: 10.3788/fgxb20123301.0026.
Effect of Mercaptopropionic Acid Molecules on Electron Transfer from CdSe Core/Shell Quantum Dots to ZnO Nanocrystal Films
The effect of mercaptopropionic acid (MPA) molecules on the charge transfer process from the quantum dots to ZnO nanocrystal films was studied in this paper by the steady-state and time-resolved photoluminescence spectroscopy. The obtained high efficiently photoluminescent CdSe-core CdS/ZnS-multishell quantum dots with few defects are air stable in quantum dot based devices. Three samples were prepared to make the measurements of time-resolved photoluminescence spectra
CdSe quantum dots film
CdSe quantum dots spun cast on ZnO nanocrystal film (CdSe/ZnO)
and MPA molecules linked CdSe quantum dots and ZnO nanocrystal film (CdSe/MPA/ZnO). The shortening of photoluminescence life times of CdSe quantum dots deposited on ZnO nanocrystal films with and without MPA molecules indicated the electron transfer process happened in the interface between CdSe quantum dots and ZnO nanocrystals. But the decreased rate of electron transfer from CdSe quantum dots to ZnO nanocrystal films with MPA molecules was found
compared to the electron transfer rate of the CdSe/ZnO sample. Considering the fact that MPA molecules did not improve the charge transfer process from CdSe quantum dots to ZnO nanocrystal films
it was indicated that the MPA molecules was not a good choice in CdSe quantum dot sensitized solar cell. The experimental result suggested that the direct adsorption of CdSe quantum dots on metal oxide nanocrystal films would obtain quantum dot sensitized solar cell with higher power conversion efficiency.
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