Details
| Original language | English |
|---|---|
| Pages (from-to) | 680-685 |
| Number of pages | 6 |
| Journal | Journal of Physical Chemistry Letters |
| Volume | 12 |
| Issue number | 1 |
| Early online date | 4 Jan 2021 |
| Publication status | Published - 14 Jan 2021 |
Abstract
Colloidal PbS nanoplatelets (NPLs) are highly interesting materials for near-infrared optoelectronic applications. We use ultrafast transient optical absorption spectroscopy to study the characteristics and dynamics of photoexcited excitons in ultrathin PbS NPLs with a cubic crystal structure. NPLs are synthesized at near room temperature from lead oleate and thiourea precursors; they show an optical absorption onset at 680 nm (1.8 eV) and photoluminescence at 720 nm (1.7 eV). By postsynthetically treating PbS NPLs with CdCl2, their photoluminescence quantum yield is strongly enhanced from 1.4% to 19.4%. The surface treatment leads to an increased lead to sulfur ratio in the structures and associated reduced nonradiative recombination. Additionally, exciton-phonon interactions in pristine and CdCl2 treated NPLs at frequencies of 1.96 and 2.04 THz are apparent from coherent oscillations in the transient absorption spectra. This study is an important step forward in unraveling and controlling the optical properties of IV-VI semiconductor NPLs.
ASJC Scopus subject areas
- Materials Science(all)
- Chemistry(all)
- Physical and Theoretical Chemistry
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In: Journal of Physical Chemistry Letters, Vol. 12, No. 1, 14.01.2021, p. 680-685.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Probing Excitons in Ultrathin PbS Nanoplatelets with Enhanced Near-Infrared Emission
AU - Manteiga Vázquez, Francisco
AU - Yu, Qianli
AU - Klepzig, Lars F.
AU - Siebbeles, Laurens D.A.
AU - Crisp, Ryan W.
AU - Lauth, Jannika
PY - 2021/1/14
Y1 - 2021/1/14
N2 - Colloidal PbS nanoplatelets (NPLs) are highly interesting materials for near-infrared optoelectronic applications. We use ultrafast transient optical absorption spectroscopy to study the characteristics and dynamics of photoexcited excitons in ultrathin PbS NPLs with a cubic crystal structure. NPLs are synthesized at near room temperature from lead oleate and thiourea precursors; they show an optical absorption onset at 680 nm (1.8 eV) and photoluminescence at 720 nm (1.7 eV). By postsynthetically treating PbS NPLs with CdCl2, their photoluminescence quantum yield is strongly enhanced from 1.4% to 19.4%. The surface treatment leads to an increased lead to sulfur ratio in the structures and associated reduced nonradiative recombination. Additionally, exciton-phonon interactions in pristine and CdCl2 treated NPLs at frequencies of 1.96 and 2.04 THz are apparent from coherent oscillations in the transient absorption spectra. This study is an important step forward in unraveling and controlling the optical properties of IV-VI semiconductor NPLs.
AB - Colloidal PbS nanoplatelets (NPLs) are highly interesting materials for near-infrared optoelectronic applications. We use ultrafast transient optical absorption spectroscopy to study the characteristics and dynamics of photoexcited excitons in ultrathin PbS NPLs with a cubic crystal structure. NPLs are synthesized at near room temperature from lead oleate and thiourea precursors; they show an optical absorption onset at 680 nm (1.8 eV) and photoluminescence at 720 nm (1.7 eV). By postsynthetically treating PbS NPLs with CdCl2, their photoluminescence quantum yield is strongly enhanced from 1.4% to 19.4%. The surface treatment leads to an increased lead to sulfur ratio in the structures and associated reduced nonradiative recombination. Additionally, exciton-phonon interactions in pristine and CdCl2 treated NPLs at frequencies of 1.96 and 2.04 THz are apparent from coherent oscillations in the transient absorption spectra. This study is an important step forward in unraveling and controlling the optical properties of IV-VI semiconductor NPLs.
UR - http://www.scopus.com/inward/record.url?scp=85099645147&partnerID=8YFLogxK
U2 - 10.48550/arXiv.2011.07174
DO - 10.48550/arXiv.2011.07174
M3 - Article
C2 - 33395303
AN - SCOPUS:85099645147
VL - 12
SP - 680
EP - 685
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
SN - 1948-7185
IS - 1
ER -