Charge generation measured for fullerene-helical nanofilament liquid crystal heterojunctions

Rebecca A. Callahan, David C. Coffey, Dong Chen, Noel A. Clark, Gary Rumbles, David M. Walba

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

The helical nanofilament (HNF) liquid crystal phase is an ordered architecture exhibiting interesting properties for charge transport. It is a small molecule self-assembly of stacked and twisted crystalline layers, which form alignable organic nanorods with half the surface area of the filaments consisting of aromatic sublayer edges. HNFs mixed with an electron acceptor generate an intriguing network for photoinduced electron transfer (PET). In this work, we characterize the structure of the HNF phase as processed into thin films with transmission electron microscopy (TEM) and X-ray diffraction (XRD). Additionally, we measure the flash-photolysis time-resolved microwave conductivity (TRMC) in samples where the HNF phase is fabricated into heterojunctions with the fullerenes C60 and PC60BM, prototypical electron acceptors for organic photovoltaics. Two distinct microstructures of the thin films were identified and compared for PET. A near-unity charge generation yield is observed in a bilayer of HNFs with C 60. Moreover, the HNF phase is shown to be 10× better at charge generation than a lamellar structuring of the same components. Thus, the HNF phase is shown to be a good charge-generation interface.

Original languageEnglish
Pages (from-to)4823-4830
Number of pages8
JournalACS Applied Materials and Interfaces
Volume6
Issue number7
DOIs
Publication statusPublished - Apr 9 2014

Fingerprint

Fullerenes
Liquid Crystals
Liquid crystals
Heterojunctions
Electrons
Thin films
Photolysis
Nanorods
Self assembly
Charge transfer
Microwaves
Crystalline materials
Transmission electron microscopy
X ray diffraction
Microstructure
Molecules

Keywords

  • bulk heterojunction
  • charge generation
  • helical nanofilaments
  • liquid crystal
  • time-resolved microwave conductivity

ASJC Scopus subject areas

  • Materials Science(all)

Cite this

Charge generation measured for fullerene-helical nanofilament liquid crystal heterojunctions. / Callahan, Rebecca A.; Coffey, David C.; Chen, Dong; Clark, Noel A.; Rumbles, Gary; Walba, David M.

In: ACS Applied Materials and Interfaces, Vol. 6, No. 7, 09.04.2014, p. 4823-4830.

Research output: Contribution to journalArticle

Callahan, Rebecca A. ; Coffey, David C. ; Chen, Dong ; Clark, Noel A. ; Rumbles, Gary ; Walba, David M. / Charge generation measured for fullerene-helical nanofilament liquid crystal heterojunctions. In: ACS Applied Materials and Interfaces. 2014 ; Vol. 6, No. 7. pp. 4823-4830.
@article{85fdc1da443646dc91769fcc7827bbe9,
title = "Charge generation measured for fullerene-helical nanofilament liquid crystal heterojunctions",
abstract = "The helical nanofilament (HNF) liquid crystal phase is an ordered architecture exhibiting interesting properties for charge transport. It is a small molecule self-assembly of stacked and twisted crystalline layers, which form alignable organic nanorods with half the surface area of the filaments consisting of aromatic sublayer edges. HNFs mixed with an electron acceptor generate an intriguing network for photoinduced electron transfer (PET). In this work, we characterize the structure of the HNF phase as processed into thin films with transmission electron microscopy (TEM) and X-ray diffraction (XRD). Additionally, we measure the flash-photolysis time-resolved microwave conductivity (TRMC) in samples where the HNF phase is fabricated into heterojunctions with the fullerenes C60 and PC60BM, prototypical electron acceptors for organic photovoltaics. Two distinct microstructures of the thin films were identified and compared for PET. A near-unity charge generation yield is observed in a bilayer of HNFs with C 60. Moreover, the HNF phase is shown to be 10× better at charge generation than a lamellar structuring of the same components. Thus, the HNF phase is shown to be a good charge-generation interface.",
keywords = "bulk heterojunction, charge generation, helical nanofilaments, liquid crystal, time-resolved microwave conductivity",
author = "Callahan, {Rebecca A.} and Coffey, {David C.} and Dong Chen and Clark, {Noel A.} and Gary Rumbles and Walba, {David M.}",
year = "2014",
month = "4",
day = "9",
doi = "10.1021/am405759d",
language = "English",
volume = "6",
pages = "4823--4830",
journal = "ACS applied materials & interfaces",
issn = "1944-8244",
publisher = "American Chemical Society",
number = "7",

}

TY - JOUR

T1 - Charge generation measured for fullerene-helical nanofilament liquid crystal heterojunctions

AU - Callahan, Rebecca A.

AU - Coffey, David C.

AU - Chen, Dong

AU - Clark, Noel A.

AU - Rumbles, Gary

AU - Walba, David M.

PY - 2014/4/9

Y1 - 2014/4/9

N2 - The helical nanofilament (HNF) liquid crystal phase is an ordered architecture exhibiting interesting properties for charge transport. It is a small molecule self-assembly of stacked and twisted crystalline layers, which form alignable organic nanorods with half the surface area of the filaments consisting of aromatic sublayer edges. HNFs mixed with an electron acceptor generate an intriguing network for photoinduced electron transfer (PET). In this work, we characterize the structure of the HNF phase as processed into thin films with transmission electron microscopy (TEM) and X-ray diffraction (XRD). Additionally, we measure the flash-photolysis time-resolved microwave conductivity (TRMC) in samples where the HNF phase is fabricated into heterojunctions with the fullerenes C60 and PC60BM, prototypical electron acceptors for organic photovoltaics. Two distinct microstructures of the thin films were identified and compared for PET. A near-unity charge generation yield is observed in a bilayer of HNFs with C 60. Moreover, the HNF phase is shown to be 10× better at charge generation than a lamellar structuring of the same components. Thus, the HNF phase is shown to be a good charge-generation interface.

AB - The helical nanofilament (HNF) liquid crystal phase is an ordered architecture exhibiting interesting properties for charge transport. It is a small molecule self-assembly of stacked and twisted crystalline layers, which form alignable organic nanorods with half the surface area of the filaments consisting of aromatic sublayer edges. HNFs mixed with an electron acceptor generate an intriguing network for photoinduced electron transfer (PET). In this work, we characterize the structure of the HNF phase as processed into thin films with transmission electron microscopy (TEM) and X-ray diffraction (XRD). Additionally, we measure the flash-photolysis time-resolved microwave conductivity (TRMC) in samples where the HNF phase is fabricated into heterojunctions with the fullerenes C60 and PC60BM, prototypical electron acceptors for organic photovoltaics. Two distinct microstructures of the thin films were identified and compared for PET. A near-unity charge generation yield is observed in a bilayer of HNFs with C 60. Moreover, the HNF phase is shown to be 10× better at charge generation than a lamellar structuring of the same components. Thus, the HNF phase is shown to be a good charge-generation interface.

KW - bulk heterojunction

KW - charge generation

KW - helical nanofilaments

KW - liquid crystal

KW - time-resolved microwave conductivity

UR - http://www.scopus.com/inward/record.url?scp=84898493833&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84898493833&partnerID=8YFLogxK

U2 - 10.1021/am405759d

DO - 10.1021/am405759d

M3 - Article

AN - SCOPUS:84898493833

VL - 6

SP - 4823

EP - 4830

JO - ACS applied materials & interfaces

JF - ACS applied materials & interfaces

SN - 1944-8244

IS - 7

ER -