Search Menu
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information
Search Scholarly Publications

Title: Effects of humidity during formation of zinc oxide electron contact layers from a diethylzinc precursor solution

Abstract

Here, this work focuses on the role of humidity in the formation of ZnO thin films from a reactive diethylzinc precursor solution for use as the electron contact layer (ECL) in organic photovoltaic (OPV) devices. This method is well suited for flexible devices because the films are annealed at 120 °C, making the process compatible with polymer substrates. ZnO films were prepared by spin coating and annealing at different relative humidity (RH) levels. It is found that RH during coating and annealing affects the chemical and physical properties of the ZnO films. Using x-ray photoelectron spectroscopy it is found that increasing RH during the formation steps produces a more stoichiometric oxide and a higher Zn/O ratio. Spectroscopic ellipsometry data shows a small decrease in the optical band gap with increased humidity, consistent with a more stoichiometric oxide. Kelvin probe measurements show that increased RH during formation results in a larger work function (i.e. further from vacuum). Consistent with these data, but counter to what might be expected, when these ZnO films are used as ECLs in OPV devices those with ZnO ECLs processed in low RH (less stoichiometric) had higher power conversion efficiency than those with high-RH processed ZnO duemore » to improved open-circuit voltage. The increase in open-circuit voltage with decreasing humidity was observed with two different donor polymers and fullerene acceptors, which shows the trend is due to changes in ZnO. The observed changes in open-circuit voltage follow the same trend as the ZnO work function indicating that the increase in open-circuit voltage with decreasing humidity is the result of improved energetics at the interface between the bulk-heterojunction and the ZnO layer due to a vacuum level shift.« less

Authors:
 [1];  [1];  [2];  [3];  [1];  [4]
+ Show Author Affiliations
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. National Renewable Energy Lab. (NREL), Golden, CO (United States); Univ. of Colorado, Boulder, CO (United States); Friedrich-Alexander Univ., Erlangen (Germany)
  3. Friedrich-Alexander Univ., Erlangen (Germany)
  4. SolarWindow Technologies, Inc., Columbia, MD (United States)
Publication Date:
Research Org.:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE NREL-Solar Window Technologies, Inc. Cooperative Research and Development Agreement (CRADA); USDOE
OSTI Identifier:
1237035
Alternate Identifier(s):
OSTI ID: 1341200
Report Number(s):
NREL/JA-5900-64538
Journal ID: ISSN 1566-1199
Grant/Contract Number:  
AC36-08GO28308
Resource Type:
Accepted Manuscript
Journal Name:
Organic Electronics
Additional Journal Information:
Journal Volume: 31; Related Information: Organic Electronics; Journal ID: ISSN 1566-1199
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; organic photovoltaics; zinc oxide; processing; humidity; contact layer

Citation Formats

Mauger, Scott A., Steirer, K. Xerxes, Boe, Jonas, Ostrowski, David P., Olson, Dana C., and Hammond, Scott R. Effects of humidity during formation of zinc oxide electron contact layers from a diethylzinc precursor solution. United States: N. p., 2016. Web. doi:10.1016/j.orgel.2016.01.012.
Copy to clipboard
Mauger, Scott A., Steirer, K. Xerxes, Boe, Jonas, Ostrowski, David P., Olson, Dana C., & Hammond, Scott R. Effects of humidity during formation of zinc oxide electron contact layers from a diethylzinc precursor solution. United States. https://doi.org/10.1016/j.orgel.2016.01.012
Copy to clipboard
Mauger, Scott A., Steirer, K. Xerxes, Boe, Jonas, Ostrowski, David P., Olson, Dana C., and Hammond, Scott R. Tue . "Effects of humidity during formation of zinc oxide electron contact layers from a diethylzinc precursor solution". United States. https://doi.org/10.1016/j.orgel.2016.01.012. https://www.osti.gov/servlets/purl/1237035.
Copy to clipboard
@article{osti_1237035,
title = {Effects of humidity during formation of zinc oxide electron contact layers from a diethylzinc precursor solution},
author = {Mauger, Scott A. and Steirer, K. Xerxes and Boe, Jonas and Ostrowski, David P. and Olson, Dana C. and Hammond, Scott R.},
abstractNote = {Here, this work focuses on the role of humidity in the formation of ZnO thin films from a reactive diethylzinc precursor solution for use as the electron contact layer (ECL) in organic photovoltaic (OPV) devices. This method is well suited for flexible devices because the films are annealed at 120 °C, making the process compatible with polymer substrates. ZnO films were prepared by spin coating and annealing at different relative humidity (RH) levels. It is found that RH during coating and annealing affects the chemical and physical properties of the ZnO films. Using x-ray photoelectron spectroscopy it is found that increasing RH during the formation steps produces a more stoichiometric oxide and a higher Zn/O ratio. Spectroscopic ellipsometry data shows a small decrease in the optical band gap with increased humidity, consistent with a more stoichiometric oxide. Kelvin probe measurements show that increased RH during formation results in a larger work function (i.e. further from vacuum). Consistent with these data, but counter to what might be expected, when these ZnO films are used as ECLs in OPV devices those with ZnO ECLs processed in low RH (less stoichiometric) had higher power conversion efficiency than those with high-RH processed ZnO due to improved open-circuit voltage. The increase in open-circuit voltage with decreasing humidity was observed with two different donor polymers and fullerene acceptors, which shows the trend is due to changes in ZnO. The observed changes in open-circuit voltage follow the same trend as the ZnO work function indicating that the increase in open-circuit voltage with decreasing humidity is the result of improved energetics at the interface between the bulk-heterojunction and the ZnO layer due to a vacuum level shift.},
doi = {10.1016/j.orgel.2016.01.012},
journal = {Organic Electronics},
number = ,
volume = 31,
place = {United States},
year = {Tue Jan 19 00:00:00 EST 2016},
month = {Tue Jan 19 00:00:00 EST 2016}
}
Copy to clipboard
Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record
https://doi.org/10.1016/j.orgel.2016.01.012
Copyright Statement
Other availability
Search WorldCat Search WorldCat to find libraries that may hold this journal
Citation Metrics:
Cited by: 3 works
Citation information provided by
Web of Science
Save / Share:
Export Metadata
Save to My Library
You must Sign In or Create an Account in order to save documents to your library.

Works referenced in this record:

Probing Charge Carrier Density in a Layer of Photodoped ZnO Nanoparticles by Spectroscopic Ellipsometry
journal, August 2010

  • Lakhwani, Girish; Roijmans, Roel F. H.; Kronemeijer, Auke J.
  • The Journal of Physical Chemistry C, Vol. 114, Issue 35
  • DOI: 10.1021/jp104846h

Evolution of microstructure and related optical properties of ZnO grown by atomic layer deposition
journal, January 2013

  • Abou Chaaya, Adib; Viter, Roman; Bechelany, Mikhael
  • Beilstein Journal of Nanotechnology, Vol. 4
  • DOI: 10.3762/bjnano.4.78

The structural and optical properties of ZnO thin films prepared at different RF sputtering power
journal, July 2013

Parameterization of the optical functions of amorphous materials in the interband region
journal, July 1996

  • Jellison, G. E.; Modine, F. A.
  • Applied Physics Letters, Vol. 69, Issue 3
  • DOI: 10.1063/1.118064

Levelised cost of electricity for organic photovoltaics
journal, February 2015

Solar cell efficiency tables (version 44): Solar cell efficiency tables
journal, June 2014

  • Green, Martin A.; Emery, Keith; Hishikawa, Yoshihiro
  • Progress in Photovoltaics: Research and Applications, Vol. 22, Issue 7
  • DOI: 10.1002/pip.2525

High performance ambient processed inverted polymer solar cells through interfacial modification with a fullerene self-assembled monolayer
journal, December 2008

  • Hau, Steven K.; Yip, Hin-Lap; Ma, Hong
  • Applied Physics Letters, Vol. 93, Issue 23
  • DOI: 10.1063/1.3028094

Influence of the hole-transport layer on the initial behavior and lifetime of inverted organic photovoltaics
journal, May 2011

  • Lloyd, Matthew T.; Peters, Craig H.; Garcia, Andres
  • Solar Energy Materials and Solar Cells, Vol. 95, Issue 5, p. 1382-1388
  • DOI: 10.1016/j.solmat.2010.12.036

Effect of ZnO layer on characteristics of conducting polymer/C60photovoltaic cell
journal, February 2004

  • Shirakawa, Tomoki; Umeda, Tokiyoshi; Hashimoto, Yuuki
  • Journal of Physics D: Applied Physics, Vol. 37, Issue 6
  • DOI: 10.1088/0022-3727/37/6/007

New Architecture for High-Efficiency Polymer Photovoltaic Cells Using Solution-Based Titanium Oxide as an Optical Spacer
journal, March 2006

  • Kim, J. Y.; Kim, S. H.; Lee, H.-H.
  • Advanced Materials, Vol. 18, Issue 5, p. 572-576
  • DOI: 10.1002/adma.200501825

Air-stable inverted flexible polymer solar cells using zinc oxide nanoparticles as an electron selective layer
journal, June 2008

  • Hau, Steven K.; Yip, Hin-Lap; Baek, Nam Seob
  • Applied Physics Letters, Vol. 92, Issue 25, Article No. 253301
  • DOI: 10.1063/1.2945281

Inverted bulk-heterojunction organic photovoltaic device using a solution-derived ZnO underlayer
journal, October 2006

  • White, M. S.; Olson, D. C.; Shaheen, S. E.
  • Applied Physics Letters, Vol. 89, Issue 14, Article No. 143517
  • DOI: 10.1063/1.2359579

Hybrid Solar Cells Using a Zinc Oxide Precursor and a Conjugated Polymer
journal, October 2005

  • Beek, W. J. E.; Slooff, L. H.; Wienk, M. M.
  • Advanced Functional Materials, Vol. 15, Issue 10, p. 1703-1707
  • DOI: 10.1002/adfm.200500201

Stability of inverted organic solar cells with ZnO contact layers deposited from precursor solutions
journal, January 2015

  • MacLeod, Bradley A.; Tremolet de Villers, Bertrand J.; Schulz, Philip
  • Energy & Environmental Science, Vol. 8, Issue 2
  • DOI: 10.1039/C4EE02488E

Inverted Polymer Solar Cells Integrated with a Low-Temperature-Annealed Sol-Gel-Derived ZnO Film as an Electron Transport Layer
journal, February 2011

  • Sun, Yanming; Seo, Jung Hwa; Takacs, Christopher J.
  • Advanced Materials, Vol. 23, Issue 14, p. 1679-1683
  • DOI: 10.1002/adma.201004301

Efficient inverted bulk-heterojunction solar cells from low-temperature processing of amorphous ZnO buffer layers
journal, January 2014

  • Jagadamma, Lethy Krishnan; Abdelsamie, Maged; El Labban, Abdulrahman
  • Journal of Materials Chemistry A, Vol. 2, Issue 33
  • DOI: 10.1039/C4TA02276A

Mechanisms of the Reactions of Diethylzinc with Isopropanol and Water
journal, May 1963

  • Herold, R. J.; Aggarwal, S. L.; Neff, V.
  • Canadian Journal of Chemistry, Vol. 41, Issue 5
  • DOI: 10.1139/v63-187

ZnO layers for opto-electronic applications from solution-based and low-temperature processing of an organometallic precursor
journal, January 2012

  • Bao Foong, Thelese Ru; Singh, Samarendra Pratap; Sonar, Prashant
  • Journal of Materials Chemistry, Vol. 22, Issue 39
  • DOI: 10.1039/c2jm34656g

ALD grown zinc oxide with controllable electrical properties
journal, June 2012

Effects of the Morphology of a ZnO Buffer Layer on the Photovoltaic Performance of Inverted Polymer Solar Cells
journal, March 2012

  • Liang, Zhiqiang; Zhang, Qifeng; Wiranwetchayan, Orawan
  • Advanced Functional Materials, Vol. 22, Issue 10
  • DOI: 10.1002/adfm.201101915

Characterization of phosphonic acid binding to zinc oxide
journal, January 2011

  • Hotchkiss, Peter J.; Malicki, Michał; Giordano, Anthony J.
  • Journal of Materials Chemistry, Vol. 21, Issue 9
  • DOI: 10.1039/c0jm02829k

Effects of ultraviolet soaking on surface electronic structures of solution processed ZnO nanoparticle films in polymer solar cells
journal, January 2014

  • Bao, Qinye; Liu, Xianjie; Xia, Yuxin
  • J. Mater. Chem. A, Vol. 2, Issue 41
  • DOI: 10.1039/C4TA02695K

Probing Charge Carrier Density in a Layer of Photodoped ZnO Nanoparticles by Spectroscopic Ellipsometry
journal, August 2010

  • Lakhwani, Girish; Roijmans, Roel F. H.; Kronemeijer, Auke J.
  • The Journal of Physical Chemistry C, Vol. 114, Issue 35
  • DOI: 10.1021/jp104846h

Parameterization of the optical functions of amorphous materials in the interband region
journal, July 1996

  • Jellison, G. E.; Modine, F. A.
  • Applied Physics Letters, Vol. 69, Issue 3
  • DOI: 10.1063/1.118064

The structural and optical properties of ZnO thin films prepared at different RF sputtering power
journal, July 2013

Evolution of microstructure and related optical properties of ZnO grown by atomic layer deposition
journal, January 2013

  • Abou Chaaya, Adib; Viter, Roman; Bechelany, Mikhael
  • Beilstein Journal of Nanotechnology, Vol. 4
  • DOI: 10.3762/bjnano.4.78

Solution Processed ZnO Hybrid Nanocomposite with Tailored Work Function for Improved Electron Transport Layer in Organic Photovoltaic Devices
journal, September 2013

  • Lee, Yun-Ju; Wang, Jian; Cheng, Samuel R.
  • ACS Applied Materials & Interfaces, Vol. 5, Issue 18
  • DOI: 10.1021/am402511t

Conjugated Phosphonic Acid Modified Zinc Oxide Electron Transport Layers for Improved Performance in Organic Solar Cells
journal, October 2014

  • Braid, Jennifer L.; Koldemir, Unsal; Sellinger, Alan
  • ACS Applied Materials & Interfaces, Vol. 6, Issue 21
  • DOI: 10.1021/am505182c

Tuning zinc oxide/organic energy level alignment using mixed triethoxysilane monolayers
journal, January 2013

  • Brenner, Thomas M.; Chen, Gang; Meinig, Erich P.
  • Journal of Materials Chemistry C, Vol. 1, Issue 37
  • DOI: 10.1039/c3tc30881b

Energy-Level Alignment at Organic/Metal and Organic/Organic Interfaces
journal, April 2009

  • Braun, Slawomir; Salaneck, William R.; Fahlman, Mats
  • Advanced Materials, Vol. 21, Issue 14-15, p. 1450-1472
  • DOI: 10.1002/adma.200802893

Cathode dependence of the open-circuit voltage of polymer:fullerene bulk heterojunction solar cells
journal, November 2003

  • Mihailetchi, V. D.; Blom, P. W. M.; Hummelen, J. C.
  • Journal of Applied Physics, Vol. 94, Issue 10
  • DOI: 10.1063/1.1620683

Universal energy-level alignment of molecules on metal oxides
journal, November 2011

  • Greiner, Mark T.; Helander, Michael G.; Tang, Wing-Man
  • Nature Materials, Vol. 11, Issue 1
  • DOI: 10.1038/nmat3159

Efficient Methano[70]fullerene/MDMO‐PPV Bulk Heterojunction Photovoltaic Cells
journal, July 2003

  • Wienk, Martijn M.; Kroon, Jan M.; Verhees, Wiljan J. H.
  • Angewandte Chemie, Vol. 115, Issue 29, p. 3493-3497
  • DOI: 10.1002/ange.200351647

Indene−C60 Bisadduct: A New Acceptor for High-Performance Polymer Solar Cells
journal, February 2010

  • He, Youjun; Chen, Hsiang-Yu; Hou, Jianhui
  • Journal of the American Chemical Society, Vol. 132, Issue 4, p. 1377-1382
  • DOI: 10.1021/ja908602j

Selective Interlayers and Contacts in Organic Photovoltaic Cells
journal, May 2011

  • Ratcliff, Erin L.; Zacher, Brian; Armstrong, Neal R.
  • The Journal of Physical Chemistry Letters, Vol. 2, Issue 11
  • DOI: 10.1021/jz2002259
    Sort by:
    [ × clear filter / sort ]

    Similar Records in DOE PAGES and OSTI.GOV collections: