Effects of Direct Solvent-Quantum Dot Interaction on the Optical Properties of Colloidal Monolayer WS2 Quantum Dots

Ho Jin, Bongkwan Baek, Doyun Kim, Fanglue Wu, James D. Batteas, Jinwoo Cheon, Dong Hee Son

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

Because of the absence of native dangling bonds on the surface of the layered transition metal dichalcogenides (TMDCs), the surface of colloidal quantum dots (QDs) of TMDCs is exposed directly to the solvent environment. Therefore, the optical and electronic properties of TMDCS QDs are expected to have stronger influence from the solvent than usual surface-passivated QDs due to more direct solvent-QD interaction. Study of such solvent effect has been difficult in colloidal QDs of TMDC due to the large spectroscopic heterogeneity resulting from the heterogeneity of the lateral size or (and) thickness in ensemble. Here, we developed a new synthesis procedure producing the highly uniform colloidal monolayer WS2 QDs exhibiting well-defined photoluminescence (PL) spectrum free from ensemble heterogeneity. Using these newly synthesized monolayer WS2 QDs, we observed the strong influence of the aromatic solvents on the PL energy and intensity of monolayer WS2 QD beyond the simple dielectric screening effect, which is considered to result from the direct electronic interaction between the valence band of the QDs and molecular orbital of the solvent. We also observed the large effect of stacking/separation equilibrium on the PL spectrum dictated by the balance between inter QD and QD-solvent interactions. The new capability to probe the effect of the solvent molecules on the optical properties of colloidal TMDC QDs will be valuable for their applications in various liquid surrounding environments.

Original languageEnglish
Pages (from-to)7471-7477
Number of pages7
JournalNano letters
Volume17
Issue number12
DOIs
Publication statusPublished - 2017 Dec 13

Fingerprint

Semiconductor quantum dots
Monolayers
Optical properties
quantum dots
optical properties
interactions
Transition metals
transition metals
Photoluminescence
photoluminescence
Dangling bonds
Molecular orbitals
Valence bands
electronics
Electronic properties
molecular orbitals
Screening
screening
valence
Molecules

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering

Cite this

Jin, Ho ; Baek, Bongkwan ; Kim, Doyun ; Wu, Fanglue ; Batteas, James D. ; Cheon, Jinwoo ; Son, Dong Hee. / Effects of Direct Solvent-Quantum Dot Interaction on the Optical Properties of Colloidal Monolayer WS2 Quantum Dots. In: Nano letters. 2017 ; Vol. 17, No. 12. pp. 7471-7477.
@article{232b3246e4ab4a93b735f8d9ff4f553a,
title = "Effects of Direct Solvent-Quantum Dot Interaction on the Optical Properties of Colloidal Monolayer WS2 Quantum Dots",
abstract = "Because of the absence of native dangling bonds on the surface of the layered transition metal dichalcogenides (TMDCs), the surface of colloidal quantum dots (QDs) of TMDCs is exposed directly to the solvent environment. Therefore, the optical and electronic properties of TMDCS QDs are expected to have stronger influence from the solvent than usual surface-passivated QDs due to more direct solvent-QD interaction. Study of such solvent effect has been difficult in colloidal QDs of TMDC due to the large spectroscopic heterogeneity resulting from the heterogeneity of the lateral size or (and) thickness in ensemble. Here, we developed a new synthesis procedure producing the highly uniform colloidal monolayer WS2 QDs exhibiting well-defined photoluminescence (PL) spectrum free from ensemble heterogeneity. Using these newly synthesized monolayer WS2 QDs, we observed the strong influence of the aromatic solvents on the PL energy and intensity of monolayer WS2 QD beyond the simple dielectric screening effect, which is considered to result from the direct electronic interaction between the valence band of the QDs and molecular orbital of the solvent. We also observed the large effect of stacking/separation equilibrium on the PL spectrum dictated by the balance between inter QD and QD-solvent interactions. The new capability to probe the effect of the solvent molecules on the optical properties of colloidal TMDC QDs will be valuable for their applications in various liquid surrounding environments.",
author = "Ho Jin and Bongkwan Baek and Doyun Kim and Fanglue Wu and Batteas, {James D.} and Jinwoo Cheon and Son, {Dong Hee}",
year = "2017",
month = "12",
day = "13",
doi = "10.1021/acs.nanolett.7b03381",
language = "English",
volume = "17",
pages = "7471--7477",
journal = "Nano Letters",
issn = "1530-6984",
publisher = "American Chemical Society",
number = "12",

}

Effects of Direct Solvent-Quantum Dot Interaction on the Optical Properties of Colloidal Monolayer WS2 Quantum Dots. / Jin, Ho; Baek, Bongkwan; Kim, Doyun; Wu, Fanglue; Batteas, James D.; Cheon, Jinwoo; Son, Dong Hee.

In: Nano letters, Vol. 17, No. 12, 13.12.2017, p. 7471-7477.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Effects of Direct Solvent-Quantum Dot Interaction on the Optical Properties of Colloidal Monolayer WS2 Quantum Dots

AU - Jin, Ho

AU - Baek, Bongkwan

AU - Kim, Doyun

AU - Wu, Fanglue

AU - Batteas, James D.

AU - Cheon, Jinwoo

AU - Son, Dong Hee

PY - 2017/12/13

Y1 - 2017/12/13

N2 - Because of the absence of native dangling bonds on the surface of the layered transition metal dichalcogenides (TMDCs), the surface of colloidal quantum dots (QDs) of TMDCs is exposed directly to the solvent environment. Therefore, the optical and electronic properties of TMDCS QDs are expected to have stronger influence from the solvent than usual surface-passivated QDs due to more direct solvent-QD interaction. Study of such solvent effect has been difficult in colloidal QDs of TMDC due to the large spectroscopic heterogeneity resulting from the heterogeneity of the lateral size or (and) thickness in ensemble. Here, we developed a new synthesis procedure producing the highly uniform colloidal monolayer WS2 QDs exhibiting well-defined photoluminescence (PL) spectrum free from ensemble heterogeneity. Using these newly synthesized monolayer WS2 QDs, we observed the strong influence of the aromatic solvents on the PL energy and intensity of monolayer WS2 QD beyond the simple dielectric screening effect, which is considered to result from the direct electronic interaction between the valence band of the QDs and molecular orbital of the solvent. We also observed the large effect of stacking/separation equilibrium on the PL spectrum dictated by the balance between inter QD and QD-solvent interactions. The new capability to probe the effect of the solvent molecules on the optical properties of colloidal TMDC QDs will be valuable for their applications in various liquid surrounding environments.

AB - Because of the absence of native dangling bonds on the surface of the layered transition metal dichalcogenides (TMDCs), the surface of colloidal quantum dots (QDs) of TMDCs is exposed directly to the solvent environment. Therefore, the optical and electronic properties of TMDCS QDs are expected to have stronger influence from the solvent than usual surface-passivated QDs due to more direct solvent-QD interaction. Study of such solvent effect has been difficult in colloidal QDs of TMDC due to the large spectroscopic heterogeneity resulting from the heterogeneity of the lateral size or (and) thickness in ensemble. Here, we developed a new synthesis procedure producing the highly uniform colloidal monolayer WS2 QDs exhibiting well-defined photoluminescence (PL) spectrum free from ensemble heterogeneity. Using these newly synthesized monolayer WS2 QDs, we observed the strong influence of the aromatic solvents on the PL energy and intensity of monolayer WS2 QD beyond the simple dielectric screening effect, which is considered to result from the direct electronic interaction between the valence band of the QDs and molecular orbital of the solvent. We also observed the large effect of stacking/separation equilibrium on the PL spectrum dictated by the balance between inter QD and QD-solvent interactions. The new capability to probe the effect of the solvent molecules on the optical properties of colloidal TMDC QDs will be valuable for their applications in various liquid surrounding environments.

UR - http://www.scopus.com/inward/record.url?scp=85038216196&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85038216196&partnerID=8YFLogxK

U2 - 10.1021/acs.nanolett.7b03381

DO - 10.1021/acs.nanolett.7b03381

M3 - Article

VL - 17

SP - 7471

EP - 7477

JO - Nano Letters

JF - Nano Letters

SN - 1530-6984

IS - 12

ER -