The University of Southampton
University of Southampton Institutional Repository

Tungsten oxides as interfacial layers for improved performance in hybrid optoelectronic devices

Tungsten oxides as interfacial layers for improved performance in hybrid optoelectronic devices
Tungsten oxides as interfacial layers for improved performance in hybrid optoelectronic devices

Tungsten oxide (WO3) films with thicknesses ranging from 30 to 100 nm were grown by Hot Filament Vapor Deposition (HFVD). Films were studied by X-Ray Photoemission Spectroscopy (XPS) and were found to be stoichiometric. The surface morphology of the films was characterized by Atomic Force Microscopy (AFM). Samples had a granular form with grains in the order of 100 nm. The surface roughness was found to increase with film thickness. HFVD WO3 films were used as conducting interfacial layers in advanced hybrid organic-inorganic optoelectronic devices. Hybrid-Organic Light Emitting Diodes (Hy-OLEDs) and Organic Photovoltaics (Hy-OPVs) were fabricated with these films as anode and/or as cathode interfacial conducting layers. The Hy-OLEDs showed significantly higher current density and a lower turn-on voltage when a thin WO3 layer was inserted at the anode/polymer interface, while when inserted at the cathode/polymer interface the device performance was found to deteriorate. The improvement was attributed to a more efficient hole injection and transport from the Fermi level of the anode to the Highest Occupied Molecular Orbital (HOMO) of a yellow emitting copolymer (YEP). On the other hand, the insertion of a thin WO3 layer at the cathode/polymer interface of Hy-OPV devices based on a polythiophene-fullerene bulk-heterojunction blend photoactive layer resulted in an increase of the produced photogenerated current, more likely due to improved electron extraction at the Al cathode.

Electronic structure, Organic optoelectronic devices, Tungsten oxide
0040-6090
5748-5753
Vasilopoulou, M.
aad1381e-d091-4090-8c7c-b74bed22393d
Palilis, L. C.
b09e9554-54da-4be5-aa08-bda894e2b86f
Georgiadou, D. G.
84977176-3678-4fb3-a3dd-2044a49c853b
Argitis, P.
ab9c4ea6-3dd2-4e34-935d-81bfb360f358
Kennou, S.
7ca6a6bd-6a05-4110-b3da-c8807f798370
Kostis, I.
681af9a6-5162-4f35-b6b1-365ea7ce7e47
Papadimitropoulos, G.
b4f1ecba-cc8a-4882-99a5-a29354a9bca7
Stathopoulos, N. A.
83a4653f-c4c8-464a-8ed1-a93c52cf3833
Iliadis, A. A.
4009bfb1-8f1d-483a-aa6b-ed81ed539b8c
Konofaos, N.
18d67477-5af4-4d52-aa0c-3b933e96fc50
Davazoglou, D.
a946cf5d-287a-4734-ba55-b180ab4525ed
Sygellou, L.
87e6de58-e0d8-46b1-aaa9-0d2150379562
Vasilopoulou, M.
aad1381e-d091-4090-8c7c-b74bed22393d
Palilis, L. C.
b09e9554-54da-4be5-aa08-bda894e2b86f
Georgiadou, D. G.
84977176-3678-4fb3-a3dd-2044a49c853b
Argitis, P.
ab9c4ea6-3dd2-4e34-935d-81bfb360f358
Kennou, S.
7ca6a6bd-6a05-4110-b3da-c8807f798370
Kostis, I.
681af9a6-5162-4f35-b6b1-365ea7ce7e47
Papadimitropoulos, G.
b4f1ecba-cc8a-4882-99a5-a29354a9bca7
Stathopoulos, N. A.
83a4653f-c4c8-464a-8ed1-a93c52cf3833
Iliadis, A. A.
4009bfb1-8f1d-483a-aa6b-ed81ed539b8c
Konofaos, N.
18d67477-5af4-4d52-aa0c-3b933e96fc50
Davazoglou, D.
a946cf5d-287a-4734-ba55-b180ab4525ed
Sygellou, L.
87e6de58-e0d8-46b1-aaa9-0d2150379562

Vasilopoulou, M., Palilis, L. C., Georgiadou, D. G., Argitis, P., Kennou, S., Kostis, I., Papadimitropoulos, G., Stathopoulos, N. A., Iliadis, A. A., Konofaos, N., Davazoglou, D. and Sygellou, L. (2011) Tungsten oxides as interfacial layers for improved performance in hybrid optoelectronic devices. Thin Solid Films, 519 (17), 5748-5753. (doi:10.1016/j.tsf.2010.12.207).

Record type: Article

Abstract

Tungsten oxide (WO3) films with thicknesses ranging from 30 to 100 nm were grown by Hot Filament Vapor Deposition (HFVD). Films were studied by X-Ray Photoemission Spectroscopy (XPS) and were found to be stoichiometric. The surface morphology of the films was characterized by Atomic Force Microscopy (AFM). Samples had a granular form with grains in the order of 100 nm. The surface roughness was found to increase with film thickness. HFVD WO3 films were used as conducting interfacial layers in advanced hybrid organic-inorganic optoelectronic devices. Hybrid-Organic Light Emitting Diodes (Hy-OLEDs) and Organic Photovoltaics (Hy-OPVs) were fabricated with these films as anode and/or as cathode interfacial conducting layers. The Hy-OLEDs showed significantly higher current density and a lower turn-on voltage when a thin WO3 layer was inserted at the anode/polymer interface, while when inserted at the cathode/polymer interface the device performance was found to deteriorate. The improvement was attributed to a more efficient hole injection and transport from the Fermi level of the anode to the Highest Occupied Molecular Orbital (HOMO) of a yellow emitting copolymer (YEP). On the other hand, the insertion of a thin WO3 layer at the cathode/polymer interface of Hy-OPV devices based on a polythiophene-fullerene bulk-heterojunction blend photoactive layer resulted in an increase of the produced photogenerated current, more likely due to improved electron extraction at the Al cathode.

Full text not available from this repository.

More information

Published date: 30 June 2011
Keywords: Electronic structure, Organic optoelectronic devices, Tungsten oxide

Identifiers

Local EPrints ID: 441591
URI: http://eprints.soton.ac.uk/id/eprint/441591
ISSN: 0040-6090
PURE UUID: babc14f7-954a-49ce-b669-d6460687a47e
ORCID for D. G. Georgiadou: ORCID iD orcid.org/0000-0002-2620-3346

Catalogue record

Date deposited: 18 Jun 2020 16:52
Last modified: 07 Oct 2020 02:27

Export record

Altmetrics

Contributors

Author: M. Vasilopoulou
Author: L. C. Palilis
Author: P. Argitis
Author: S. Kennou
Author: I. Kostis
Author: G. Papadimitropoulos
Author: N. A. Stathopoulos
Author: A. A. Iliadis
Author: N. Konofaos
Author: D. Davazoglou
Author: L. Sygellou

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×