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  • Effects of hole transporting PEDOT:PSS on the photoemission of upconverted hot electron in Mn-doped CdS/ZnS quantum dots
Title: Effects of hole transporting PEDOT:PSS on the photoemission of upconverted hot electron in Mn-doped CdS/ZnS quantum dots
In this work, we investigated the effect of hole transporting poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) interfacing with Mn-doped CdS/ZnS quantum dots (QDs) deposited on an indium tin oxide (ITO) substrate on the photoemission of upconverted hot electrons under weak continuous wave photoexcitation in a vacuum. Among the various factors that can influence the photoemission of the upconverted hot electrons, we studied the role of PEDOT:PSS in facilitating the hole transfer from QDs and altering the energy of photoemitted hot electrons. Compared to hot electrons emitted from QDs deposited directly on the ITO substrate, the addition of the PEDOT:PSS layer between the QD and ITO layers increased the energy of the photoemitted hot electrons. The increased energy of the photoemitted hot electrons is attributed in part to the reduced steady-state positive charge on the QDs under continuous photoexcitation, which reduces the energy required to eject the electron from the conduction band.  more » « less
Award ID(s):
2003961
PAR ID:
10483398
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
159
Issue:
5
ISSN:
0021-9606
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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