TY - JOUR
T1 - Ultrafast charge separation from highly reductive ZnTe/CdSe type II quantum dots
AU - Jin, Shengye
AU - Zhang, Jun
AU - Schaller, Richard D.
AU - Rajh, Tijana
AU - Wiederrecht, Gary P.
PY - 2012/8/2
Y1 - 2012/8/2
N2 - The low electron affinity of ZnTe quantum dots (QDs) makes it of interest for critically important photocatalytic processes. However, studies of charge transfer from such materials to adsorbates have not been reported. Here, the ultrafast internal and external charge separation dynamics in ZnTe/CdSe core/shell type II QDs have been studied through femtosecond transient absorption spectroscopy. The internal electron transfer time from a ZnTe core to a CdSe shell was found to be 0.67 ps, while the external electron transfer time from QDs to adsorbed molecules was found to be <0.2 ps. Such a fast external charge separation time is due to the extraordinarily high conduction band energy potential of this QD composition. This study indicates the preservation of high photodriven reductive abilities in the ZnTe/CdSe core/shell type II heterostructures.
AB - The low electron affinity of ZnTe quantum dots (QDs) makes it of interest for critically important photocatalytic processes. However, studies of charge transfer from such materials to adsorbates have not been reported. Here, the ultrafast internal and external charge separation dynamics in ZnTe/CdSe core/shell type II QDs have been studied through femtosecond transient absorption spectroscopy. The internal electron transfer time from a ZnTe core to a CdSe shell was found to be 0.67 ps, while the external electron transfer time from QDs to adsorbed molecules was found to be <0.2 ps. Such a fast external charge separation time is due to the extraordinarily high conduction band energy potential of this QD composition. This study indicates the preservation of high photodriven reductive abilities in the ZnTe/CdSe core/shell type II heterostructures.
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U2 - 10.1021/jz3008886
DO - 10.1021/jz3008886
M3 - Article
AN - SCOPUS:84864780099
VL - 3
SP - 2052
EP - 2058
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
SN - 1948-7185
IS - 15
ER -