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Title: Cu−In−Ga−S quantum dot composition-dependent device performance of electrically driven light-emitting diodes

Abstract

Colloidal synthesis of ternary and quaternary quantum dots (QDs) of In/Ga ratio-varied Cu−In{sub 1−x}−Ga{sub x}−S (CIGS) with nominal x = 0, 0.5, 0.7, and 1 and their application for the fabrication of quantum dot-light-emitting diodes (QLEDs) are reported. Four QLEDs having CIGS QDs with different compositions are all solution-processed in the framework of multilayered structure, where QD emitting layer is sandwiched by hybrid charge transport layers of poly(9-vinlycarbazole) and ZnO nanoparticles. The device performance such as luminance and efficiency is found to be strongly dependent on the composition of CIGS QDs, and well interpreted by the device energy level diagram proposed through the determination of QD valence band minima by photoelectron emission spectroscopic measurement.

Authors:
; ; ;  [1]; ;  [2]
  1. Department of Materials Science and Engineering, Hongik University, Seoul 121-791 (Korea, Republic of)
  2. Institute of Advanced Composite Materials, Korea Institute of Science and Technology, Jeonbuk 565-905 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22350815
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 13; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CHARGE TRANSPORT; CONCENTRATION RATIO; COPPER COMPOUNDS; EFFICIENCY; EQUIPMENT; GALLIUM; GALLIUM COMPOUNDS; INDIUM; INDIUM COMPOUNDS; LAYERS; LIGHT EMITTING DIODES; NANOPARTICLES; QUANTUM DOTS; SOLID SOLUTIONS; SULFUR COMPOUNDS; SYNTHESIS; ZINC OXIDES

Citation Formats

Kim, Jong-Hoon, Lee, Ki-Heon, Jo, Dae-Yeon, Yang, Heesun, E-mail: hyang@hongik.ac.kr, Lee, Yangjin, and Hwang, Jun Yeon. Cu−In−Ga−S quantum dot composition-dependent device performance of electrically driven light-emitting diodes. United States: N. p., 2014. Web. doi:10.1063/1.4896911.
Kim, Jong-Hoon, Lee, Ki-Heon, Jo, Dae-Yeon, Yang, Heesun, E-mail: hyang@hongik.ac.kr, Lee, Yangjin, & Hwang, Jun Yeon. Cu−In−Ga−S quantum dot composition-dependent device performance of electrically driven light-emitting diodes. United States. doi:10.1063/1.4896911.
Kim, Jong-Hoon, Lee, Ki-Heon, Jo, Dae-Yeon, Yang, Heesun, E-mail: hyang@hongik.ac.kr, Lee, Yangjin, and Hwang, Jun Yeon. 2014. "Cu−In−Ga−S quantum dot composition-dependent device performance of electrically driven light-emitting diodes". United States. doi:10.1063/1.4896911.
@article{osti_22350815,
title = {Cu−In−Ga−S quantum dot composition-dependent device performance of electrically driven light-emitting diodes},
author = {Kim, Jong-Hoon and Lee, Ki-Heon and Jo, Dae-Yeon and Yang, Heesun, E-mail: hyang@hongik.ac.kr and Lee, Yangjin and Hwang, Jun Yeon},
abstractNote = {Colloidal synthesis of ternary and quaternary quantum dots (QDs) of In/Ga ratio-varied Cu−In{sub 1−x}−Ga{sub x}−S (CIGS) with nominal x = 0, 0.5, 0.7, and 1 and their application for the fabrication of quantum dot-light-emitting diodes (QLEDs) are reported. Four QLEDs having CIGS QDs with different compositions are all solution-processed in the framework of multilayered structure, where QD emitting layer is sandwiched by hybrid charge transport layers of poly(9-vinlycarbazole) and ZnO nanoparticles. The device performance such as luminance and efficiency is found to be strongly dependent on the composition of CIGS QDs, and well interpreted by the device energy level diagram proposed through the determination of QD valence band minima by photoelectron emission spectroscopic measurement.},
doi = {10.1063/1.4896911},
journal = {Applied Physics Letters},
number = 13,
volume = 105,
place = {United States},
year = 2014,
month = 9
}
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