Band-Tail Transport of CuSCN: Origin of Hole Extraction Enhancement in Organic Photovoltaics

Minju Kim; Soohyung Park; Junkyeong Jeong; Dongguen Shin; Jimin Kim; Sae Hee Ryu; Keun Su Kim; Hyunbok Lee; Yeonjin Yi

doi:10.1021/acs.jpclett.6b01039

Band-Tail Transport of CuSCN: Origin of Hole Extraction Enhancement in Organic Photovoltaics

Minju Kim, Soohyung Park, Junkyeong Jeong, Dongguen Shin, Jimin Kim, Sae Hee Ryu, Keun Su Kim, Hyunbok Lee, Yeonjin Yi

Department of Physics

Research output: Contribution to journal › Article › peer-review

33 Citations (Scopus)

Abstract

Copper thiocyanate (CuSCN) is known as a promising hole transport layer in organic photovoltaics (OPVs) due to its good hole conduction and exciton blocking abilities with high transparency. Despite its successful device applications, the origin of its hole extraction enhancement in OPVs has not yet been understood. Here, we investigated the electronic structure of CuSCN and the energy level alignment at the poly(3-hexylthiophene-2,5-diyl) (P3HT)/CuSCN/ITO interfaces using ultraviolet photoelectron spectroscopy. The band-tail states of CuSCN close to the Fermi level (E_F) were observed at 0.25 eV below the E_F, leading to good hole transport. The CuSCN interlayer significantly reduces the hole transport barrier between ITO and P3HT due to its high work function and band-tail states. The barrier reduction leads to enhanced current density-voltage characteristics of hole-dominated devices. These results provide the origin of hole-extraction enhancement by CuSCN and insights for further application.

Original language	English
Pages (from-to)	2856-2861
Number of pages	6
Journal	Journal of Physical Chemistry Letters
Volume	7
Issue number	14
DOIs	https://doi.org/10.1021/acs.jpclett.6b01039
Publication status	Published - 2016 Jul 21

Bibliographical note

Funding Information:
This study was supported by National Research Foundation of K o r e a ( N R F - 2 0 1 5 R 1 C 1 A 1 A 0 1 0 5 5 0 2 6 a n d 2012M3A7B4049801), Samsung Display and Defense Acquisition Program Administration (DAPA), the Agency for Defense Development (ADD), and Yonsei University Future-Leading Research Initiative of 2014 (2015-22-0132).

Publisher Copyright:
© 2016 American Chemical Society.

All Science Journal Classification (ASJC) codes

Materials Science(all)
Physical and Theoretical Chemistry

Access to Document

10.1021/acs.jpclett.6b01039

Cite this

@article{e8ad73f08ebf4cf2826816413f82f2ce,

title = "Band-Tail Transport of CuSCN: Origin of Hole Extraction Enhancement in Organic Photovoltaics",

abstract = "Copper thiocyanate (CuSCN) is known as a promising hole transport layer in organic photovoltaics (OPVs) due to its good hole conduction and exciton blocking abilities with high transparency. Despite its successful device applications, the origin of its hole extraction enhancement in OPVs has not yet been understood. Here, we investigated the electronic structure of CuSCN and the energy level alignment at the poly(3-hexylthiophene-2,5-diyl) (P3HT)/CuSCN/ITO interfaces using ultraviolet photoelectron spectroscopy. The band-tail states of CuSCN close to the Fermi level (EF) were observed at 0.25 eV below the EF, leading to good hole transport. The CuSCN interlayer significantly reduces the hole transport barrier between ITO and P3HT due to its high work function and band-tail states. The barrier reduction leads to enhanced current density-voltage characteristics of hole-dominated devices. These results provide the origin of hole-extraction enhancement by CuSCN and insights for further application.",

author = "Minju Kim and Soohyung Park and Junkyeong Jeong and Dongguen Shin and Jimin Kim and Ryu, {Sae Hee} and Kim, {Keun Su} and Hyunbok Lee and Yeonjin Yi",

note = "Funding Information: This study was supported by National Research Foundation of K o r e a ( N R F - 2 0 1 5 R 1 C 1 A 1 A 0 1 0 5 5 0 2 6 a n d 2012M3A7B4049801), Samsung Display and Defense Acquisition Program Administration (DAPA), the Agency for Defense Development (ADD), and Yonsei University Future-Leading Research Initiative of 2014 (2015-22-0132). Publisher Copyright: {\textcopyright} 2016 American Chemical Society.",

year = "2016",

month = jul,

day = "21",

doi = "10.1021/acs.jpclett.6b01039",

language = "English",

volume = "7",

pages = "2856--2861",

journal = "Journal of Physical Chemistry Letters",

issn = "1948-7185",

publisher = "American Chemical Society",

number = "14",

}

TY - JOUR

T1 - Band-Tail Transport of CuSCN

T2 - Origin of Hole Extraction Enhancement in Organic Photovoltaics

AU - Kim, Minju

AU - Park, Soohyung

AU - Jeong, Junkyeong

AU - Shin, Dongguen

AU - Kim, Jimin

AU - Ryu, Sae Hee

AU - Kim, Keun Su

AU - Lee, Hyunbok

AU - Yi, Yeonjin

N1 - Funding Information: This study was supported by National Research Foundation of K o r e a ( N R F - 2 0 1 5 R 1 C 1 A 1 A 0 1 0 5 5 0 2 6 a n d 2012M3A7B4049801), Samsung Display and Defense Acquisition Program Administration (DAPA), the Agency for Defense Development (ADD), and Yonsei University Future-Leading Research Initiative of 2014 (2015-22-0132). Publisher Copyright: © 2016 American Chemical Society.

PY - 2016/7/21

Y1 - 2016/7/21

N2 - Copper thiocyanate (CuSCN) is known as a promising hole transport layer in organic photovoltaics (OPVs) due to its good hole conduction and exciton blocking abilities with high transparency. Despite its successful device applications, the origin of its hole extraction enhancement in OPVs has not yet been understood. Here, we investigated the electronic structure of CuSCN and the energy level alignment at the poly(3-hexylthiophene-2,5-diyl) (P3HT)/CuSCN/ITO interfaces using ultraviolet photoelectron spectroscopy. The band-tail states of CuSCN close to the Fermi level (EF) were observed at 0.25 eV below the EF, leading to good hole transport. The CuSCN interlayer significantly reduces the hole transport barrier between ITO and P3HT due to its high work function and band-tail states. The barrier reduction leads to enhanced current density-voltage characteristics of hole-dominated devices. These results provide the origin of hole-extraction enhancement by CuSCN and insights for further application.

AB - Copper thiocyanate (CuSCN) is known as a promising hole transport layer in organic photovoltaics (OPVs) due to its good hole conduction and exciton blocking abilities with high transparency. Despite its successful device applications, the origin of its hole extraction enhancement in OPVs has not yet been understood. Here, we investigated the electronic structure of CuSCN and the energy level alignment at the poly(3-hexylthiophene-2,5-diyl) (P3HT)/CuSCN/ITO interfaces using ultraviolet photoelectron spectroscopy. The band-tail states of CuSCN close to the Fermi level (EF) were observed at 0.25 eV below the EF, leading to good hole transport. The CuSCN interlayer significantly reduces the hole transport barrier between ITO and P3HT due to its high work function and band-tail states. The barrier reduction leads to enhanced current density-voltage characteristics of hole-dominated devices. These results provide the origin of hole-extraction enhancement by CuSCN and insights for further application.

UR - http://www.scopus.com/inward/record.url?scp=84979555472&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84979555472&partnerID=8YFLogxK

U2 - 10.1021/acs.jpclett.6b01039

DO - 10.1021/acs.jpclett.6b01039

M3 - Article

AN - SCOPUS:84979555472

SN - 1948-7185

VL - 7

SP - 2856

EP - 2861

JO - Journal of Physical Chemistry Letters

JF - Journal of Physical Chemistry Letters

IS - 14

ER -

Band-Tail Transport of CuSCN: Origin of Hole Extraction Enhancement in Organic Photovoltaics

Abstract

Bibliographical note

All Science Journal Classification (ASJC) codes

Access to Document

Other files and links

Fingerprint

Cite this