期刊
CHEMISTRY-A EUROPEAN JOURNAL
卷 20, 期 41, 页码 13305-13313出版社
WILEY-V C H VERLAG GMBH
DOI: 10.1002/chem.201403267
关键词
charge transfer; electron infection; hole transfer quantum dots; sensitizers
资金
- DAE-SRC Outstanding Research Investigator Award [DAE-SRC/2012/21/13-BRNS]
- CSIR
- DAE
Ultrafast charge-transfer dynamics has been demonstrated in CdSe quantum dots (QD), CdSe/ZnS type-I core shell, and CdSe/CdTe type-II core shell nanocrystals after sensitizing the QD materials by aurin tricarboxylic acid (ATC), in which CdSe QD and ATC form a charge-transfer complex. Energy level diagrams suggest that the conduction and valence band of CdSe lies below the LUMO and the HOMO level of ATC, respectively, thus signifying that the photoexcited hole in CdSe can be transferred to ATC and that photoexcited ATC can inject electrons into CdSe QD, which has been confirmed by steady state and time-resolved luminescence studies and also by femtosecond time-resolved absorption measurements. The effect of shell materi- als (for both type-I and type-II) on charge-transfer processes has been demonstrated. Electron injection in all the systems were measured to be <150 fs. However, the hole transfer time varied from 900 fs to 6 ps depending on the type of materials. The hole-transfer process was found to be most efficient in CdSe QD. On the other hand, it has been found to be facilitated in CdSe/CdTe type-II and retarded in CdSe/ ZnS type-I core shell materials. Interestingly, electron injection from photoexcited ATC to both CdSe/CdTe type-II and CdSe/ZnS type-I core shell has been found to be more efficient as compared to pure CdSe QD. Our observation suggests the potential of quantum dot core shell super sensitizers for developing more efficient quantum dot solar cells.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据