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Title: Facet-Specific Ligand Interactions on Ternary AgSbS 2 Colloidal Quantum Dots

Abstract

Silver dimetal chalcogenide (Ag-V-VI 2) ternary quantum dots (QDs) are emerging lead-free materials for optoelectronic devices due to their NIR band gaps, large absorption coefficients, and superior electronic properties. However, thin film-based devices of the ternary QDs still lag behind due to the lack of understanding of the surface chemistry, compared to that of lead chalcogenide QDs even with the same crystal structure. Here in this paper, the surface ligand interactions of AgSbS 2 QDs, synthesized with 1-dodecanethiol used as a stabilizer, are studied. For nonpolar (1 0 0) surfaces, it is suggested that the thiolate ligands are associated with the crystal lattices, thus preventing surface oxidation by protecting sulfur after air-exposure, as confirmed through optical and surface chemical analysis. Otherwise, silver rich (1 1 1) surfaces are passivated by thiolate ligands, allowing ligand exchange processes for the conductive films. This in-depth investigation of the surface chemistry of ternary QDs will prompt the performance enhancement of their optoelectronic devices.

Authors:
ORCiD logo [1];  [2];  [3];  [1];  [4];  [3]; ORCiD logo [4]
  1. Korea Inst. of Machinery and Materials, Daejeon (Korea, Republic of). Nano-Convergence Systems Research Division
  2. Ajou Univ., Suwon (Republic of Korea). Dept. of Molecular Science and Technology
  3. National Renewable Energy Lab. (NREL), Golden, CO (United States). Chemical and Materials Sciences Center
  4. Korea Inst. of Machinery and Materials, Daejeon (Korea, Republic of). Nano-Convergence Systems Research Division; Korea Univ. of Science and Technology (UST), Daejeon (Republic of Korea). Dept. of Nanomechatronics
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE); Korea Institute for Advancement of Technology (KIAT)
OSTI Identifier:
1409306
Report Number(s):
NREL/JA-5900-70532
Journal ID: ISSN 0947-6539
Grant/Contract Number:
AC36-08GO28308; NRF-2016R1A2B3014182; 2014R1A5A1009799
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Chemistry - A European Journal
Additional Journal Information:
Journal Volume: 23; Journal Issue: 66; Journal ID: ISSN 0947-6539
Publisher:
ChemPubSoc Europe
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 77 NANOSCIENCE AND NANOTECHNOLOGY; AGSBS2; I-V-VI2; QUANTUM DOTS; SURFACE CHEMISTRY; TERNARY

Citation Formats

Choi, Hyekyoung, Kim, Sungwoo, Luther, Joseph M., Kim, Sang-Wook, Shin, Dongwoon, Beard, Matthew C., and Jeong, Sohee. Facet-Specific Ligand Interactions on Ternary AgSbS2 Colloidal Quantum Dots. United States: N. p., 2017. Web. doi:10.1002/chem.201703681.
Choi, Hyekyoung, Kim, Sungwoo, Luther, Joseph M., Kim, Sang-Wook, Shin, Dongwoon, Beard, Matthew C., & Jeong, Sohee. Facet-Specific Ligand Interactions on Ternary AgSbS2 Colloidal Quantum Dots. United States. doi:10.1002/chem.201703681.
Choi, Hyekyoung, Kim, Sungwoo, Luther, Joseph M., Kim, Sang-Wook, Shin, Dongwoon, Beard, Matthew C., and Jeong, Sohee. Tue . "Facet-Specific Ligand Interactions on Ternary AgSbS2 Colloidal Quantum Dots". United States. doi:10.1002/chem.201703681.
@article{osti_1409306,
title = {Facet-Specific Ligand Interactions on Ternary AgSbS2 Colloidal Quantum Dots},
author = {Choi, Hyekyoung and Kim, Sungwoo and Luther, Joseph M. and Kim, Sang-Wook and Shin, Dongwoon and Beard, Matthew C. and Jeong, Sohee},
abstractNote = {Silver dimetal chalcogenide (Ag-V-VI2) ternary quantum dots (QDs) are emerging lead-free materials for optoelectronic devices due to their NIR band gaps, large absorption coefficients, and superior electronic properties. However, thin film-based devices of the ternary QDs still lag behind due to the lack of understanding of the surface chemistry, compared to that of lead chalcogenide QDs even with the same crystal structure. Here in this paper, the surface ligand interactions of AgSbS2 QDs, synthesized with 1-dodecanethiol used as a stabilizer, are studied. For nonpolar (1 0 0) surfaces, it is suggested that the thiolate ligands are associated with the crystal lattices, thus preventing surface oxidation by protecting sulfur after air-exposure, as confirmed through optical and surface chemical analysis. Otherwise, silver rich (1 1 1) surfaces are passivated by thiolate ligands, allowing ligand exchange processes for the conductive films. This in-depth investigation of the surface chemistry of ternary QDs will prompt the performance enhancement of their optoelectronic devices.},
doi = {10.1002/chem.201703681},
journal = {Chemistry - A European Journal},
number = 66,
volume = 23,
place = {United States},
year = {Tue Nov 07 00:00:00 EST 2017},
month = {Tue Nov 07 00:00:00 EST 2017}
}

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