Solvent effect in dynamic superstructures from au nanoparticles and cdte nanowires: Experimental observation and theoretical description

Jaebeom Lee, Azamat Orazbayev, Alexander O. Govorov, Nicholas A. Kotov

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Solvent effects on luminescence in nanocolloids are typically related to changes in the dielectric constant around the light-emitting species, but they can have a completely different nature in complex dynamic nanoscale assemblies. Hybrid superstructures were assembled from Au nanoparticles (NPs) and CdTe nanowires (NWs) via poly(ethylene glycol) (PEG) bridges and provide the first example of solvent-responsive dynamic nanoscale assemblies from NWs. The photoluminescence (PL) intensity of the CdTe NWs was found to be dependent on the hydrophilic/hydrophobic balance of the solvent (water, methanol, ethanol, and 2-propanol) surrounding the superstructure and displayed slow equilibration kinetics. PL gradually decreased over a period of 2000 s by ca. 50% for ethanol and ca. 70% for 2-propanol, whereas it remained constant for water and methanol. This phenomenon was attributed to the solvent dependence of the radius of gyration (RF) of the PEG bridges between the NPs and NWs, which swells in ethanol and 2-propanol. The average distance between the NPs and NWs affects the plasmon-exciton interactions responsible for optical processes in the superstructure, and expansion results in a decrease of the luminescence enhancement of Cd Te by Au NPs. Theoretical modeling was carried out to confirm the mechanism of the solvent effect. Exciton-plasmon resonance was described as a combination of two components: field enhancement and energy transfer. Although carrying some limitations and being inherently approximate, this approach was able to describe the distance dependence of the PL intensity of NP-NW system well. The suggested theoretical model expands the understanding of plasmon-exciton electronic systems and can be applied to many semiconductor-metal superstructures.

Original languageEnglish
Pages (from-to)1404-1410
Number of pages7
JournalJournal of Physical Chemistry C
Volume114
Issue number3
DOIs
Publication statusPublished - Jan 28 2010
Externally publishedYes

Fingerprint

Nanowires
nanowires
Nanoparticles
nanoparticles
2-Propanol
Propanol
Excitons
Photoluminescence
Ethanol
ethyl alcohol
excitons
photoluminescence
assemblies
Polyethylene glycols
Methanol
Luminescence
glycols
ethylene
methyl alcohol
luminescence

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Electronic, Optical and Magnetic Materials
  • Surfaces, Coatings and Films
  • Energy(all)

Cite this

Solvent effect in dynamic superstructures from au nanoparticles and cdte nanowires : Experimental observation and theoretical description. / Lee, Jaebeom; Orazbayev, Azamat; Govorov, Alexander O.; Kotov, Nicholas A.

In: Journal of Physical Chemistry C, Vol. 114, No. 3, 28.01.2010, p. 1404-1410.

Research output: Contribution to journalArticle

Lee, Jaebeom ; Orazbayev, Azamat ; Govorov, Alexander O. ; Kotov, Nicholas A. / Solvent effect in dynamic superstructures from au nanoparticles and cdte nanowires : Experimental observation and theoretical description. In: Journal of Physical Chemistry C. 2010 ; Vol. 114, No. 3. pp. 1404-1410.
@article{9c746e2a28a445de86b1cb1ac41cfc18,
title = "Solvent effect in dynamic superstructures from au nanoparticles and cdte nanowires: Experimental observation and theoretical description",
abstract = "Solvent effects on luminescence in nanocolloids are typically related to changes in the dielectric constant around the light-emitting species, but they can have a completely different nature in complex dynamic nanoscale assemblies. Hybrid superstructures were assembled from Au nanoparticles (NPs) and CdTe nanowires (NWs) via poly(ethylene glycol) (PEG) bridges and provide the first example of solvent-responsive dynamic nanoscale assemblies from NWs. The photoluminescence (PL) intensity of the CdTe NWs was found to be dependent on the hydrophilic/hydrophobic balance of the solvent (water, methanol, ethanol, and 2-propanol) surrounding the superstructure and displayed slow equilibration kinetics. PL gradually decreased over a period of 2000 s by ca. 50{\%} for ethanol and ca. 70{\%} for 2-propanol, whereas it remained constant for water and methanol. This phenomenon was attributed to the solvent dependence of the radius of gyration (RF) of the PEG bridges between the NPs and NWs, which swells in ethanol and 2-propanol. The average distance between the NPs and NWs affects the plasmon-exciton interactions responsible for optical processes in the superstructure, and expansion results in a decrease of the luminescence enhancement of Cd Te by Au NPs. Theoretical modeling was carried out to confirm the mechanism of the solvent effect. Exciton-plasmon resonance was described as a combination of two components: field enhancement and energy transfer. Although carrying some limitations and being inherently approximate, this approach was able to describe the distance dependence of the PL intensity of NP-NW system well. The suggested theoretical model expands the understanding of plasmon-exciton electronic systems and can be applied to many semiconductor-metal superstructures.",
author = "Jaebeom Lee and Azamat Orazbayev and Govorov, {Alexander O.} and Kotov, {Nicholas A.}",
year = "2010",
month = "1",
day = "28",
doi = "10.1021/jp809780m",
language = "English",
volume = "114",
pages = "1404--1410",
journal = "Journal of Physical Chemistry C",
issn = "1932-7447",
publisher = "American Chemical Society",
number = "3",

}

TY - JOUR

T1 - Solvent effect in dynamic superstructures from au nanoparticles and cdte nanowires

T2 - Experimental observation and theoretical description

AU - Lee, Jaebeom

AU - Orazbayev, Azamat

AU - Govorov, Alexander O.

AU - Kotov, Nicholas A.

PY - 2010/1/28

Y1 - 2010/1/28

N2 - Solvent effects on luminescence in nanocolloids are typically related to changes in the dielectric constant around the light-emitting species, but they can have a completely different nature in complex dynamic nanoscale assemblies. Hybrid superstructures were assembled from Au nanoparticles (NPs) and CdTe nanowires (NWs) via poly(ethylene glycol) (PEG) bridges and provide the first example of solvent-responsive dynamic nanoscale assemblies from NWs. The photoluminescence (PL) intensity of the CdTe NWs was found to be dependent on the hydrophilic/hydrophobic balance of the solvent (water, methanol, ethanol, and 2-propanol) surrounding the superstructure and displayed slow equilibration kinetics. PL gradually decreased over a period of 2000 s by ca. 50% for ethanol and ca. 70% for 2-propanol, whereas it remained constant for water and methanol. This phenomenon was attributed to the solvent dependence of the radius of gyration (RF) of the PEG bridges between the NPs and NWs, which swells in ethanol and 2-propanol. The average distance between the NPs and NWs affects the plasmon-exciton interactions responsible for optical processes in the superstructure, and expansion results in a decrease of the luminescence enhancement of Cd Te by Au NPs. Theoretical modeling was carried out to confirm the mechanism of the solvent effect. Exciton-plasmon resonance was described as a combination of two components: field enhancement and energy transfer. Although carrying some limitations and being inherently approximate, this approach was able to describe the distance dependence of the PL intensity of NP-NW system well. The suggested theoretical model expands the understanding of plasmon-exciton electronic systems and can be applied to many semiconductor-metal superstructures.

AB - Solvent effects on luminescence in nanocolloids are typically related to changes in the dielectric constant around the light-emitting species, but they can have a completely different nature in complex dynamic nanoscale assemblies. Hybrid superstructures were assembled from Au nanoparticles (NPs) and CdTe nanowires (NWs) via poly(ethylene glycol) (PEG) bridges and provide the first example of solvent-responsive dynamic nanoscale assemblies from NWs. The photoluminescence (PL) intensity of the CdTe NWs was found to be dependent on the hydrophilic/hydrophobic balance of the solvent (water, methanol, ethanol, and 2-propanol) surrounding the superstructure and displayed slow equilibration kinetics. PL gradually decreased over a period of 2000 s by ca. 50% for ethanol and ca. 70% for 2-propanol, whereas it remained constant for water and methanol. This phenomenon was attributed to the solvent dependence of the radius of gyration (RF) of the PEG bridges between the NPs and NWs, which swells in ethanol and 2-propanol. The average distance between the NPs and NWs affects the plasmon-exciton interactions responsible for optical processes in the superstructure, and expansion results in a decrease of the luminescence enhancement of Cd Te by Au NPs. Theoretical modeling was carried out to confirm the mechanism of the solvent effect. Exciton-plasmon resonance was described as a combination of two components: field enhancement and energy transfer. Although carrying some limitations and being inherently approximate, this approach was able to describe the distance dependence of the PL intensity of NP-NW system well. The suggested theoretical model expands the understanding of plasmon-exciton electronic systems and can be applied to many semiconductor-metal superstructures.

UR - http://www.scopus.com/inward/record.url?scp=77249153346&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77249153346&partnerID=8YFLogxK

U2 - 10.1021/jp809780m

DO - 10.1021/jp809780m

M3 - Article

AN - SCOPUS:77249153346

VL - 114

SP - 1404

EP - 1410

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 3

ER -