Characteristics of gradient-interface-structured ZnCdSSe quantum dots with modified interface and its application to quantum-dot-sensitized solar cells

Da Woon Jeong, Jae Yup Kim, Han Wook Seo, Kyoung Mook Lim, Min Jae Ko, Tae Yeon Seong, Bum Sung Kim

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Colloidal quantum dots (QDs) are attractive materials for application in photovoltaics, LEDs, displays, and bio devices owing to their unique properties. In this study, we synthesized gradient-interface-structured ZnCdSSe QDs and modified the interface based on a thermodynamic simulation to investigate its optical and physical properties. In addition, the interface was modified by increasing the molar concentration of Se. QDs at the modified interface were applied to QD-sensitized solar cells, which showed a 25.5% increase in photoelectric conversion efficiency owing to the reduced electron confinement effect. The increase seems to be caused by the excited electrons being relatively easily transferred to the level of TiO2 owing to the reduced electron confinement effect. Consequently, the electron confinement effect was observed to be reduced by increasing the ZnSe (or Zn1-xCdxSe)-rich phase at the interface. This means that, based on the thermodynamic simulation, the interface between the core QDs and the surface of the QDs can be controlled. The improvement of optical and electronic properties by controlling interfaces and surfaces during the synthesis of QDs, as reported in this work, can be useful for many applications beyond solar cells.

Original languageEnglish
JournalApplied Surface Science
DOIs
Publication statusAccepted/In press - 2017

Fingerprint

Semiconductor quantum dots
Solar cells
Electrons
Optical properties
Thermodynamics
Electronic properties
Conversion efficiency
Light emitting diodes
Physical properties
Display devices

Keywords

  • Gradient interface
  • Modified interface
  • QDSCs
  • Quantum dots
  • Solar cell

ASJC Scopus subject areas

  • Surfaces, Coatings and Films

Cite this

Characteristics of gradient-interface-structured ZnCdSSe quantum dots with modified interface and its application to quantum-dot-sensitized solar cells. / Jeong, Da Woon; Kim, Jae Yup; Seo, Han Wook; Lim, Kyoung Mook; Ko, Min Jae; Seong, Tae Yeon; Kim, Bum Sung.

In: Applied Surface Science, 2017.

Research output: Contribution to journalArticle

@article{a712e8cb281340cfbaff929f9fc38366,
title = "Characteristics of gradient-interface-structured ZnCdSSe quantum dots with modified interface and its application to quantum-dot-sensitized solar cells",
abstract = "Colloidal quantum dots (QDs) are attractive materials for application in photovoltaics, LEDs, displays, and bio devices owing to their unique properties. In this study, we synthesized gradient-interface-structured ZnCdSSe QDs and modified the interface based on a thermodynamic simulation to investigate its optical and physical properties. In addition, the interface was modified by increasing the molar concentration of Se. QDs at the modified interface were applied to QD-sensitized solar cells, which showed a 25.5{\%} increase in photoelectric conversion efficiency owing to the reduced electron confinement effect. The increase seems to be caused by the excited electrons being relatively easily transferred to the level of TiO2 owing to the reduced electron confinement effect. Consequently, the electron confinement effect was observed to be reduced by increasing the ZnSe (or Zn1-xCdxSe)-rich phase at the interface. This means that, based on the thermodynamic simulation, the interface between the core QDs and the surface of the QDs can be controlled. The improvement of optical and electronic properties by controlling interfaces and surfaces during the synthesis of QDs, as reported in this work, can be useful for many applications beyond solar cells.",
keywords = "Gradient interface, Modified interface, QDSCs, Quantum dots, Solar cell",
author = "Jeong, {Da Woon} and Kim, {Jae Yup} and Seo, {Han Wook} and Lim, {Kyoung Mook} and Ko, {Min Jae} and Seong, {Tae Yeon} and Kim, {Bum Sung}",
year = "2017",
doi = "10.1016/j.apsusc.2017.07.025",
language = "English",
journal = "Applied Surface Science",
issn = "0169-4332",
publisher = "Elsevier",

}

TY - JOUR

T1 - Characteristics of gradient-interface-structured ZnCdSSe quantum dots with modified interface and its application to quantum-dot-sensitized solar cells

AU - Jeong, Da Woon

AU - Kim, Jae Yup

AU - Seo, Han Wook

AU - Lim, Kyoung Mook

AU - Ko, Min Jae

AU - Seong, Tae Yeon

AU - Kim, Bum Sung

PY - 2017

Y1 - 2017

N2 - Colloidal quantum dots (QDs) are attractive materials for application in photovoltaics, LEDs, displays, and bio devices owing to their unique properties. In this study, we synthesized gradient-interface-structured ZnCdSSe QDs and modified the interface based on a thermodynamic simulation to investigate its optical and physical properties. In addition, the interface was modified by increasing the molar concentration of Se. QDs at the modified interface were applied to QD-sensitized solar cells, which showed a 25.5% increase in photoelectric conversion efficiency owing to the reduced electron confinement effect. The increase seems to be caused by the excited electrons being relatively easily transferred to the level of TiO2 owing to the reduced electron confinement effect. Consequently, the electron confinement effect was observed to be reduced by increasing the ZnSe (or Zn1-xCdxSe)-rich phase at the interface. This means that, based on the thermodynamic simulation, the interface between the core QDs and the surface of the QDs can be controlled. The improvement of optical and electronic properties by controlling interfaces and surfaces during the synthesis of QDs, as reported in this work, can be useful for many applications beyond solar cells.

AB - Colloidal quantum dots (QDs) are attractive materials for application in photovoltaics, LEDs, displays, and bio devices owing to their unique properties. In this study, we synthesized gradient-interface-structured ZnCdSSe QDs and modified the interface based on a thermodynamic simulation to investigate its optical and physical properties. In addition, the interface was modified by increasing the molar concentration of Se. QDs at the modified interface were applied to QD-sensitized solar cells, which showed a 25.5% increase in photoelectric conversion efficiency owing to the reduced electron confinement effect. The increase seems to be caused by the excited electrons being relatively easily transferred to the level of TiO2 owing to the reduced electron confinement effect. Consequently, the electron confinement effect was observed to be reduced by increasing the ZnSe (or Zn1-xCdxSe)-rich phase at the interface. This means that, based on the thermodynamic simulation, the interface between the core QDs and the surface of the QDs can be controlled. The improvement of optical and electronic properties by controlling interfaces and surfaces during the synthesis of QDs, as reported in this work, can be useful for many applications beyond solar cells.

KW - Gradient interface

KW - Modified interface

KW - QDSCs

KW - Quantum dots

KW - Solar cell

UR - http://www.scopus.com/inward/record.url?scp=85023612863&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85023612863&partnerID=8YFLogxK

U2 - 10.1016/j.apsusc.2017.07.025

DO - 10.1016/j.apsusc.2017.07.025

M3 - Article

JO - Applied Surface Science

JF - Applied Surface Science

SN - 0169-4332

ER -