TY - JOUR
T1 - Two-Dimensional Diffusion of Excitons in a Perylene Diimide Monolayer Quenched by a Fullerene Heterojunction
AU - Kerfoot, James
AU - Korolkov, Vladimir V.
AU - Svatek, Simon A.
AU - Alkhamisi, Manal
AU - Taniguchi, Takashi
AU - Watanabe, Kenji
AU - Parkinson, Patrick W.
AU - Beton, Peter H.
PY - 2019
Y1 - 2019
N2 -
The structural and functional properties of organic heterojunctions play a vitally important role in the operation of organic devices, but their properties are difficult to measure directly due to the buried interfaces that are typically formed. We have grown model heterojunctions consisting of two monolayer-thick organic semiconductors and used these bilayers to explore the two-dimensional dynamics of excitons. The heterostructures are formed by sequential deposition of monolayers of perylene-3,4,9,10-tetracarboxylic-3,4,9,10-diimide (PTCDI) and fullerene (C
60
) on hexagonal boron nitride (hBN). The morphology of these bilayers was characterized using atomic force microscopy and showed clear differences in the C
60
growth kinetics on hBN and PTCDI. The variation in the fluorescence of PTCDI-C
60
heterostructures with increasing fullerene coverage showed a reduction in intensity consistent with exciton diffusion and quenching. We use a simple model for the intensity dependence to determine the two-dimensional exciton diffusion length in a PTCDI monolayer, finding a value of 17 ± 3 nm for this parameter.
AB -
The structural and functional properties of organic heterojunctions play a vitally important role in the operation of organic devices, but their properties are difficult to measure directly due to the buried interfaces that are typically formed. We have grown model heterojunctions consisting of two monolayer-thick organic semiconductors and used these bilayers to explore the two-dimensional dynamics of excitons. The heterostructures are formed by sequential deposition of monolayers of perylene-3,4,9,10-tetracarboxylic-3,4,9,10-diimide (PTCDI) and fullerene (C
60
) on hexagonal boron nitride (hBN). The morphology of these bilayers was characterized using atomic force microscopy and showed clear differences in the C
60
growth kinetics on hBN and PTCDI. The variation in the fluorescence of PTCDI-C
60
heterostructures with increasing fullerene coverage showed a reduction in intensity consistent with exciton diffusion and quenching. We use a simple model for the intensity dependence to determine the two-dimensional exciton diffusion length in a PTCDI monolayer, finding a value of 17 ± 3 nm for this parameter.
U2 - 10.1021/acs.jpcc.9b01413
DO - 10.1021/acs.jpcc.9b01413
M3 - Article
AN - SCOPUS:85065870397
SN - 1932-7447
VL - 123
SP - 12249
EP - 12254
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 19
ER -