Details
| Original language | English |
|---|---|
| Pages (from-to) | 48271-48280 |
| Number of pages | 10 |
| Journal | ACS Applied Materials and Interfaces |
| Volume | 11 |
| Issue number | 51 |
| Early online date | 28 Nov 2019 |
| Publication status | Published - 26 Dec 2019 |
Abstract
We report an optically gated transistor composed of CdSe nanocrystals (NCs), sensitized with the dye zinc β-tetraaminophthalocyanine for operation in the first telecom window. This device shows a high ON/OFF ratio of 6 orders of magnitude in the red spectral region and an unprecedented 4.5 orders of magnitude at 847 nm. By transient absorption spectroscopy, we reveal that this unexpected infrared sensitivity is due to electron transfer from the dye to the CdSe NCs within 5 ps. We show by time-resolved photocurrent measurements that this enables fast rise times during near-infrared optical gating of 47 ± 11 ns. Electronic coupling and accelerated nonradiative recombination of charge carriers at the interface between the dye and the CdSe NCs are further corroborated by steady-state and time-resolved photoluminescence measurements. Field-effect transistor measurements indicate that the increase in photocurrent upon laser illumination is mainly due to the increase in the carrier concentration while the mobility remains unchanged. Our results illustrate that organic dyes as ligands for NCs invoke new optoelectronic functionalities, such as fast optical gating at sub-bandgap optical excitation energies.
Keywords
- fluorescence lifetimes, nanocrystals, optical transistor, organic dyes, time-resolved photocurrent, transient absorption spectroscopy
ASJC Scopus subject areas
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: ACS Applied Materials and Interfaces, Vol. 11, No. 51, 26.12.2019, p. 48271-48280.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Fast, Infrared-Active Optical Transistors Based on Dye-Sensitized CdSe Nanocrystals
AU - Kumar, Krishan
AU - Liu, Quan
AU - Hiller, Jonas
AU - Schedel, Christine
AU - Maier, Andre
AU - Meixner, Alfred
AU - Braun, Kai
AU - Lauth, Jannika
AU - Scheele, Marcus
N1 - Funding information: The authors acknowledge the DFG for support under Grant SCHE1905/3 and under Germany’s Excellence Strategy within the Cluster of Excellence PhoenixD (EXC 2122, Project ID 390833453). The time-resolved photocurrent measurements have been funded by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No 802822).
PY - 2019/12/26
Y1 - 2019/12/26
N2 - We report an optically gated transistor composed of CdSe nanocrystals (NCs), sensitized with the dye zinc β-tetraaminophthalocyanine for operation in the first telecom window. This device shows a high ON/OFF ratio of 6 orders of magnitude in the red spectral region and an unprecedented 4.5 orders of magnitude at 847 nm. By transient absorption spectroscopy, we reveal that this unexpected infrared sensitivity is due to electron transfer from the dye to the CdSe NCs within 5 ps. We show by time-resolved photocurrent measurements that this enables fast rise times during near-infrared optical gating of 47 ± 11 ns. Electronic coupling and accelerated nonradiative recombination of charge carriers at the interface between the dye and the CdSe NCs are further corroborated by steady-state and time-resolved photoluminescence measurements. Field-effect transistor measurements indicate that the increase in photocurrent upon laser illumination is mainly due to the increase in the carrier concentration while the mobility remains unchanged. Our results illustrate that organic dyes as ligands for NCs invoke new optoelectronic functionalities, such as fast optical gating at sub-bandgap optical excitation energies.
AB - We report an optically gated transistor composed of CdSe nanocrystals (NCs), sensitized with the dye zinc β-tetraaminophthalocyanine for operation in the first telecom window. This device shows a high ON/OFF ratio of 6 orders of magnitude in the red spectral region and an unprecedented 4.5 orders of magnitude at 847 nm. By transient absorption spectroscopy, we reveal that this unexpected infrared sensitivity is due to electron transfer from the dye to the CdSe NCs within 5 ps. We show by time-resolved photocurrent measurements that this enables fast rise times during near-infrared optical gating of 47 ± 11 ns. Electronic coupling and accelerated nonradiative recombination of charge carriers at the interface between the dye and the CdSe NCs are further corroborated by steady-state and time-resolved photoluminescence measurements. Field-effect transistor measurements indicate that the increase in photocurrent upon laser illumination is mainly due to the increase in the carrier concentration while the mobility remains unchanged. Our results illustrate that organic dyes as ligands for NCs invoke new optoelectronic functionalities, such as fast optical gating at sub-bandgap optical excitation energies.
KW - fluorescence lifetimes
KW - nanocrystals
KW - optical transistor
KW - organic dyes
KW - time-resolved photocurrent
KW - transient absorption spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=85076751176&partnerID=8YFLogxK
U2 - 10.1021/acsami.9b18236
DO - 10.1021/acsami.9b18236
M3 - Article
C2 - 31778068
AN - SCOPUS:85076751176
VL - 11
SP - 48271
EP - 48280
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
SN - 1944-8244
IS - 51
ER -