Nanoporous silver thin films: Multifunctional platforms for influencing chain morphology and optical properties of conjugated polymers

Zeqing Shen, Deirdre M O'Carroll

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Disordered nanoporous silver (NPAg) thin films fabricated by a thermally assisted dewetting method are employed as a platform to influence chain alignment, morphology, and optical properties of three well-known conjugated polymers. Grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements show that the porous structure of the metal induces close π-π stacking of poly(3-hexylthiophene) (P3HT) chains and extended, planar chain conformations of poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) and poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,8-diyl)] (F8BT). A greater degree of vertically-oriented P3HT chains are found on NPAg compared with planar Ag. However, PFO and F8BT chain alignment is only affected when pore size is large. The optical properties of NPAg films are investigated by transmission and back-scattering spectroscopies. Strong back-scattering is observed for all NPAg morphologies, especially for NPAg with small pore sizes. Photoluminescence spectroscopy of conjugated polymer layers on NPAg showed pronounced emission enhancements (up to factors of 26) relative to layers on glass. The enhancements are attributed primarily to: 1) redistribution of conjugated polymer emission by Ag; 2) redirection of emission by polymer-filled nanopores; and 3) local electromagnetic field effects. This work demonstrates the potential of NPAg-thin films to influence molecular chain morphology and to improve light-extraction in organic optoelectronic devices. Nanoporous metal films are multifunctional platforms that affect both the morphology and emission properties of conjugated polymer layer coatings. Nanoporous silver can reorient and/or planarize a fraction of conjugated polymer molecules in the pores. Photoluminescence emission enhancements of up to 26 are possible from conjugated polymer layers using nanoporous silver instead of bare glass substrates.

Original languageEnglish
Pages (from-to)3302-3313
Number of pages12
JournalAdvanced Functional Materials
Volume25
Issue number22
DOIs
Publication statusPublished - Jun 1 2015

Fingerprint

Conjugated polymers
Silver
platforms
Optical properties
silver
optical properties
Thin films
polymers
thin films
Pore size
porosity
Electromagnetic field effects
Metals
augmentation
Scattering
Filled polymers
scattering
alignment
Glass
Nanopores

Keywords

  • enhanced photoluminescence
  • grazing incidence X-ray scattering
  • nanostructures
  • polymer chain alignment

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Condensed Matter Physics
  • Electrochemistry

Cite this

@article{609e72b10bbb4065893e19c118d89c78,
title = "Nanoporous silver thin films: Multifunctional platforms for influencing chain morphology and optical properties of conjugated polymers",
abstract = "Disordered nanoporous silver (NPAg) thin films fabricated by a thermally assisted dewetting method are employed as a platform to influence chain alignment, morphology, and optical properties of three well-known conjugated polymers. Grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements show that the porous structure of the metal induces close π-π stacking of poly(3-hexylthiophene) (P3HT) chains and extended, planar chain conformations of poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) and poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,8-diyl)] (F8BT). A greater degree of vertically-oriented P3HT chains are found on NPAg compared with planar Ag. However, PFO and F8BT chain alignment is only affected when pore size is large. The optical properties of NPAg films are investigated by transmission and back-scattering spectroscopies. Strong back-scattering is observed for all NPAg morphologies, especially for NPAg with small pore sizes. Photoluminescence spectroscopy of conjugated polymer layers on NPAg showed pronounced emission enhancements (up to factors of 26) relative to layers on glass. The enhancements are attributed primarily to: 1) redistribution of conjugated polymer emission by Ag; 2) redirection of emission by polymer-filled nanopores; and 3) local electromagnetic field effects. This work demonstrates the potential of NPAg-thin films to influence molecular chain morphology and to improve light-extraction in organic optoelectronic devices. Nanoporous metal films are multifunctional platforms that affect both the morphology and emission properties of conjugated polymer layer coatings. Nanoporous silver can reorient and/or planarize a fraction of conjugated polymer molecules in the pores. Photoluminescence emission enhancements of up to 26 are possible from conjugated polymer layers using nanoporous silver instead of bare glass substrates.",
keywords = "enhanced photoluminescence, grazing incidence X-ray scattering, nanostructures, polymer chain alignment",
author = "Zeqing Shen and O'Carroll, {Deirdre M}",
year = "2015",
month = "6",
day = "1",
doi = "10.1002/adfm.201500456",
language = "English",
volume = "25",
pages = "3302--3313",
journal = "Advanced Functional Materials",
issn = "1616-301X",
publisher = "Wiley-VCH Verlag",
number = "22",

}

TY - JOUR

T1 - Nanoporous silver thin films

T2 - Multifunctional platforms for influencing chain morphology and optical properties of conjugated polymers

AU - Shen, Zeqing

AU - O'Carroll, Deirdre M

PY - 2015/6/1

Y1 - 2015/6/1

N2 - Disordered nanoporous silver (NPAg) thin films fabricated by a thermally assisted dewetting method are employed as a platform to influence chain alignment, morphology, and optical properties of three well-known conjugated polymers. Grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements show that the porous structure of the metal induces close π-π stacking of poly(3-hexylthiophene) (P3HT) chains and extended, planar chain conformations of poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) and poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,8-diyl)] (F8BT). A greater degree of vertically-oriented P3HT chains are found on NPAg compared with planar Ag. However, PFO and F8BT chain alignment is only affected when pore size is large. The optical properties of NPAg films are investigated by transmission and back-scattering spectroscopies. Strong back-scattering is observed for all NPAg morphologies, especially for NPAg with small pore sizes. Photoluminescence spectroscopy of conjugated polymer layers on NPAg showed pronounced emission enhancements (up to factors of 26) relative to layers on glass. The enhancements are attributed primarily to: 1) redistribution of conjugated polymer emission by Ag; 2) redirection of emission by polymer-filled nanopores; and 3) local electromagnetic field effects. This work demonstrates the potential of NPAg-thin films to influence molecular chain morphology and to improve light-extraction in organic optoelectronic devices. Nanoporous metal films are multifunctional platforms that affect both the morphology and emission properties of conjugated polymer layer coatings. Nanoporous silver can reorient and/or planarize a fraction of conjugated polymer molecules in the pores. Photoluminescence emission enhancements of up to 26 are possible from conjugated polymer layers using nanoporous silver instead of bare glass substrates.

AB - Disordered nanoporous silver (NPAg) thin films fabricated by a thermally assisted dewetting method are employed as a platform to influence chain alignment, morphology, and optical properties of three well-known conjugated polymers. Grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements show that the porous structure of the metal induces close π-π stacking of poly(3-hexylthiophene) (P3HT) chains and extended, planar chain conformations of poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) and poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,8-diyl)] (F8BT). A greater degree of vertically-oriented P3HT chains are found on NPAg compared with planar Ag. However, PFO and F8BT chain alignment is only affected when pore size is large. The optical properties of NPAg films are investigated by transmission and back-scattering spectroscopies. Strong back-scattering is observed for all NPAg morphologies, especially for NPAg with small pore sizes. Photoluminescence spectroscopy of conjugated polymer layers on NPAg showed pronounced emission enhancements (up to factors of 26) relative to layers on glass. The enhancements are attributed primarily to: 1) redistribution of conjugated polymer emission by Ag; 2) redirection of emission by polymer-filled nanopores; and 3) local electromagnetic field effects. This work demonstrates the potential of NPAg-thin films to influence molecular chain morphology and to improve light-extraction in organic optoelectronic devices. Nanoporous metal films are multifunctional platforms that affect both the morphology and emission properties of conjugated polymer layer coatings. Nanoporous silver can reorient and/or planarize a fraction of conjugated polymer molecules in the pores. Photoluminescence emission enhancements of up to 26 are possible from conjugated polymer layers using nanoporous silver instead of bare glass substrates.

KW - enhanced photoluminescence

KW - grazing incidence X-ray scattering

KW - nanostructures

KW - polymer chain alignment

UR - http://www.scopus.com/inward/record.url?scp=85027955082&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85027955082&partnerID=8YFLogxK

U2 - 10.1002/adfm.201500456

DO - 10.1002/adfm.201500456

M3 - Article

AN - SCOPUS:85027955082

VL - 25

SP - 3302

EP - 3313

JO - Advanced Functional Materials

JF - Advanced Functional Materials

SN - 1616-301X

IS - 22

ER -