skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Investigation of ultra-thin titania films as hole-blocking contacts for organic photovoltaics


Ultra-thin (0.5–10 nm) plasma-enhanced atomic layer deposited titanium oxide (TiO x) films deposited on indium-tin-oxide contacts, are investigated as hole-blocking interlayers using conventional electrochemistry, Si-diodes, and heterojunction (P3HT:PCBM) organic photovoltaics (OPVs).

 [1];  [2];  [2];  [3];  [3];  [4];  [4];  [2];  [5]
  1. School of Mechanical Engineering; Georgia Institute of Technology; Atlanta, USA
  2. Department of Chemistry & Biochemistry; University of Arizona; Tucson, USA
  3. National Renewable Energy Laboratory (NREL); Golden, USA
  4. Institut d'Electronique, de Microélectronique et de Nanotechnologie (IEMN); Le Centre National de la Recherche Scientifique (CNRS); Villeneuve d'Ascq, France
  5. School of Mechanical Engineering; Georgia Institute of Technology; Atlanta, USA; School of Materials Science and Engineering; Center for Organic Photonics and Electronics
Publication Date:
Research Org.:
Energy Frontier Research Centers (EFRC) (United States). Center for Interface Science: Solar Electric Materials (CISSEM)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
DOE Contract Number:  
Resource Type:
Journal Article
Journal Name:
Journal of Materials Chemistry. A
Additional Journal Information:
Journal Volume: 3; Journal Issue: 33; Related Information: CISSEM partners with the University of Arizona (lead); Georgia Institute of Technology; National Renewable Energy Laboratory; Princeton University; University of Washington; Journal ID: ISSN 2050-7488
Royal Society of Chemistry
Country of Publication:
United States
solar (photovoltaic), electrodes - solar, charge transport, synthesis (novel materials), synthesis (self-assembly), synthesis (scalable processing)

Citation Formats

Kim, Hyungchul, Ou, Kai-Lin, Wu, Xin, Ndione, Paul F., Berry, Joseph, Lambert, Yannick, Mélin, Thierry, Armstrong, Neal R., and Graham, Samuel. Investigation of ultra-thin titania films as hole-blocking contacts for organic photovoltaics. United States: N. p., 2015. Web. doi:10.1039/C5TA04687D.
Kim, Hyungchul, Ou, Kai-Lin, Wu, Xin, Ndione, Paul F., Berry, Joseph, Lambert, Yannick, Mélin, Thierry, Armstrong, Neal R., & Graham, Samuel. Investigation of ultra-thin titania films as hole-blocking contacts for organic photovoltaics. United States. doi:10.1039/C5TA04687D.
Kim, Hyungchul, Ou, Kai-Lin, Wu, Xin, Ndione, Paul F., Berry, Joseph, Lambert, Yannick, Mélin, Thierry, Armstrong, Neal R., and Graham, Samuel. Thu . "Investigation of ultra-thin titania films as hole-blocking contacts for organic photovoltaics". United States. doi:10.1039/C5TA04687D.
title = {Investigation of ultra-thin titania films as hole-blocking contacts for organic photovoltaics},
author = {Kim, Hyungchul and Ou, Kai-Lin and Wu, Xin and Ndione, Paul F. and Berry, Joseph and Lambert, Yannick and Mélin, Thierry and Armstrong, Neal R. and Graham, Samuel},
abstractNote = {Ultra-thin (0.5–10 nm) plasma-enhanced atomic layer deposited titanium oxide (TiOx) films deposited on indium-tin-oxide contacts, are investigated as hole-blocking interlayers using conventional electrochemistry, Si-diodes, and heterojunction (P3HT:PCBM) organic photovoltaics (OPVs).},
doi = {10.1039/C5TA04687D},
journal = {Journal of Materials Chemistry. A},
issn = {2050-7488},
number = 33,
volume = 3,
place = {United States},
year = {2015},
month = {1}

Works referenced in this record:

Atomic layer deposition of TiO 2 and Al 2 O 3 thin films and nanolaminates
journal, December 2005

Solar Cells Based on Inks of n-Type Colloidal Quantum Dots
journal, September 2014

  • Ning, Zhijun; Dong, Haopeng; Zhang, Qiong
  • ACS Nano, Vol. 8, Issue 10
  • DOI: 10.1021/nn503569p

Integer Charge Transfer and Hybridization at an Organic Semiconductor/Conductive Oxide Interface
journal, February 2015

  • Gruenewald, Marco; Schirra, Laura K.; Winget, Paul
  • The Journal of Physical Chemistry C, Vol. 119, Issue 9
  • DOI: 10.1021/jp512153b

Ultrathin TiO 2 Films on ZnO Electron-Collecting Layers of Inverted Organic Solar Cell
journal, October 2011

  • Seo, Hyun Ook; Park, Sun-Young; Shim, Won Hyun
  • The Journal of Physical Chemistry C, Vol. 115, Issue 43
  • DOI: 10.1021/jp2063589

Power losses in bilayer inverted small molecule organic solar cells
journal, December 2012

  • Trinh, Cong; Bakke, Jonathan R.; Brennan, Thomas P.
  • Applied Physics Letters, Vol. 101, Issue 23
  • DOI: 10.1063/1.4769440

Highly durable inverted-type organic solar cell using amorphous titanium oxide as electron collection electrode inserted between ITO and organic layer
journal, November 2008

  • Kuwabara, Takayuki; Nakayama, Taketoshi; Uozumi, Konosuke
  • Solar Energy Materials and Solar Cells, Vol. 92, Issue 11
  • DOI: 10.1016/j.solmat.2008.06.012

Thickness-Dependent Hydroxylation of MgO(001) Thin Films
journal, October 2010

  • Carrasco, Esther; Brown, Matthew A.; Sterrer, Martin
  • The Journal of Physical Chemistry C, Vol. 114, Issue 42
  • DOI: 10.1021/jp105294e

Influence of ZnO interlayer on the performance of inverted organic photovoltaic device
journal, August 2011

Transparent Conducting Oxides for Photovoltaics: Manipulation of Fermi Level, Work Function and Energy Band Alignment
journal, November 2010

  • Klein, Andreas; Körber, Christoph; Wachau, André
  • Materials, Vol. 3, Issue 11
  • DOI: 10.3390/ma3114892

Nucleation and growth of thin films
journal, April 1984

  • Venables, J. A.; Spiller, G. D. T.; Hanbucken, M.
  • Reports on Progress in Physics, Vol. 47, Issue 4
  • DOI: 10.1088/0034-4885/47/4/002

On the structure, morphology and electrical conductivities of titanium oxide thin films
journal, June 2002

Electron Energetics at Surfaces and Interfaces: Concepts and Experiments
journal, February 2003

A Universal Method to Produce Low-Work Function Electrodes for Organic Electronics
journal, April 2012

Polymer solar cells with enhanced open-circuit voltage and efficiency
journal, November 2009

  • Chen, Hsiang-Yu; Hou, Jianhui; Zhang, Shaoqing
  • Nature Photonics, Vol. 3, Issue 11, p. 649-653
  • DOI: 10.1038/nphoton.2009.192

Inverted bulk-heterojunction organic solar cell using chemical bath deposited titanium oxide as electron collection layer
journal, June 2010

Atomic Layer Deposition of High Performance Ultrathin TiO 2 Blocking Layers for Dye-Sensitized Solar Cells
journal, May 2013

Low Temperature Plasma-Enhanced Atomic Layer Deposition of Metal Oxide Thin Films
journal, January 2010

  • Potts, S. E.; Keuning, W.; Langereis, E.
  • Journal of The Electrochemical Society, Vol. 157, Issue 7
  • DOI: 10.1149/1.3428705

Electrical Properties of Some Titanium Oxides
journal, November 1969

Atomic layer deposition (ALD): from precursors to thin film structures
journal, April 2002

25th Anniversary Article: A Decade of Organic/Polymeric Photovoltaic Research
journal, September 2013

Atomic layer-deposited tunnel oxide stabilizes silicon photoanodes for water oxidation
journal, June 2011

  • Chen, Yi Wei; Prange, Jonathan D.; Dühnen, Simon
  • Nature Materials, Vol. 10, Issue 7
  • DOI: 10.1038/nmat3047

Amorphous TiO2 coatings stabilize Si, GaAs, and GaP photoanodes for efficient water oxidation
journal, May 2014

Organic photovoltaics with high stability sustained for 100 days without encapsulation fabricated using atomic layer deposition
journal, April 2012

  • Park, Sun-Young; Seo, Hyun Ook; Kim, Kwang-Dae
  • physica status solidi (RRL) - Rapid Research Letters, Vol. 6, Issue 5
  • DOI: 10.1002/pssr.201206070

Room temperature solution-processed electron transport layer for organic solar cells
journal, October 2013

Thin-Film Organic Electronic Devices
journal, August 2009

Fluorine Substituted Conjugated Polymer of Medium Band Gap Yields 7% Efficiency in Polymer−Fullerene Solar Cells
journal, March 2011

  • Price, Samuel C.; Stuart, Andrew C.; Yang, Liqiang
  • Journal of the American Chemical Society, Vol. 133, Issue 12
  • DOI: 10.1021/ja1112595

Surface Composition and Electrical and Electrochemical Properties of Freshly Deposited and Acid-Etched Indium Tin Oxide Electrodes
journal, October 2007

  • Brumbach, Michael; Veneman, P. Alex; Marrikar, F. Saneeha
  • Langmuir, Vol. 23, Issue 22
  • DOI: 10.1021/la701754u

The surface science of titanium dioxide
journal, January 2003

Photovoltaic Properties of Bulk-Heterojunction Organic Solar Cell with Ultrathin Titanium Oxide Nanosheet as Electron Selective Layer
journal, April 2013

  • Itoh, Eiji; Maruyama, Yasutake; Fukuda, Katsutoshi
  • Japanese Journal of Applied Physics, Vol. 52, Issue 4S
  • DOI: 10.7567/JJAP.52.04CK05

Hole-blocking titanium-oxide/silicon heterojunction and its application to photovoltaics
journal, May 2013

  • Avasthi, Sushobhan; McClain, William E.; Man, Gabriel
  • Applied Physics Letters, Vol. 102, Issue 20
  • DOI: 10.1063/1.4803446

Morphological Characterization of a Low-Bandgap Crystalline Polymer:PCBM Bulk Heterojunction Solar Cells
journal, July 2011

  • Lu, Haiyun; Akgun, Bulent; Russell, Thomas P.
  • Advanced Energy Materials, Vol. 1, Issue 5
  • DOI: 10.1002/aenm.201100128

Highly efficient inverted organic photovoltaics using solution based titanium oxide as electron selective contact
journal, December 2006

  • Waldauf, C.; Morana, M.; Denk, P.
  • Applied Physics Letters, Vol. 89, Issue 23
  • DOI: 10.1063/1.2402890

Improved Inverted Organic Solar Cells With a Sol–Gel Derived Indium-Doped Zinc Oxide Buffer Layer
journal, November 2010

  • Kyaw, Aung Ko Ko; Sun, Xiaowei; Zhao, De Wei
  • IEEE Journal of Selected Topics in Quantum Electronics, Vol. 16, Issue 6
  • DOI: 10.1109/JSTQE.2009.2039200

Efficient semitransparent inverted organic solar cells with indium tin oxide top electrode
journal, June 2009

  • Schmidt, H.; Flügge, H.; Winkler, T.
  • Applied Physics Letters, Vol. 94, Issue 24
  • DOI: 10.1063/1.3154556

Research Update: Doping ZnO and TiO 2 for solar cells
journal, December 2013

  • Hoye, Robert L. Z.; Musselman, Kevin P.; MacManus-Driscoll, Judith L.
  • APL Materials, Vol. 1, Issue 6
  • DOI: 10.1063/1.4833475

Enhanced Power Conversion Efficiency of Inverted Organic Solar Cells with a Ga-Doped ZnO Nanostructured Thin Film Prepared Using Aqueous Solution
journal, June 2010

  • Shin, Kyung-Sik; Lee, Kang-Hyuck; Lee, Hyun Hwi
  • The Journal of Physical Chemistry C, Vol. 114, Issue 37
  • DOI: 10.1021/jp1013658

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

Atomic layer deposition of TiO2 from TiCl4 and O3
journal, September 2013

Titanium dioxide electron-selective interlayers created by chemical vapor deposition for inverted configuration organic solar cells
journal, January 2013

  • Ou, Kai-Lin; Tadytin, Delvin; Xerxes Steirer, K.
  • Journal of Materials Chemistry A, Vol. 1, Issue 23
  • DOI: 10.1039/c3ta10894e

Review of the fundamentals of thin-film growth
journal, January 2002

Hydrophilic properties of nano-TiO2 thin films deposited by RF magnetron sputtering
journal, January 2007

Cyclic voltammetry on electrode surfaces covered with porous layers: An analysis of electron transfer kinetics at single-walled carbon nanotube modified electrodes
journal, August 2008

  • Streeter, Ian; Wildgoose, Gregory G.; Shao, Lidong
  • Sensors and Actuators B: Chemical, Vol. 133, Issue 2
  • DOI: 10.1016/j.snb.2008.03.015

Electrochemical Monitoring of TiO 2 Atomic Layer Deposition by Chronoamperometry and Scanning Electrochemical Microscopy
journal, October 2013

  • Satpati, Ashis K.; Arroyo-Currás, Netzahualcóyotl; Ji, Li
  • Chemistry of Materials, Vol. 25, Issue 21
  • DOI: 10.1021/cm401635v

Scanning Electrochemical Microscopy and Conductive Probe Atomic Force Microscopy Studies of Hydrogen-Terminated Boron-Doped Diamond Electrodes with Different Doping Levels
journal, September 2004

  • Holt, Katherine B.; Bard, Allen J.; Show, Yoshiyuki
  • The Journal of Physical Chemistry B, Vol. 108, Issue 39
  • DOI: 10.1021/jp048222x

Flexible inverted polymer solar cells containing an amorphous titanium oxide electron collection electrode
journal, January 2011

The probing depth in photoemission and auger-electron spectroscopy
journal, January 1974

An inverted organic solar cell employing a sol-gel derived ZnO electron selective layer and thermal evaporated MoO3 hole selective layer
journal, December 2008

  • Kyaw, A. K. K.; Sun, X. W.; Jiang, C. Y.
  • Applied Physics Letters, Vol. 93, Issue 22
  • DOI: 10.1063/1.3039076

The Modification of Indium Tin Oxide with Phosphonic Acids: Mechanism of Binding, Tuning of Surface Properties, and Potential for Use in Organic Electronic Applications
journal, October 2011

  • Hotchkiss, Peter J.; Jones, Simon C.; Paniagua, Sergio A.
  • Accounts of Chemical Research, Vol. 45, Issue 3
  • DOI: 10.1021/ar200119g

Sequential deposition as a route to high-performance perovskite-sensitized solar cells
journal, July 2013

  • Burschka, Julian; Pellet, Norman; Moon, Soo-Jin
  • Nature, Vol. 499, Issue 7458, p. 316-319
  • DOI: 10.1038/nature12340

Inverted organic solar cells using a solution processed aluminum-doped zinc oxide buffer layer
journal, September 2011

Nanocrystalline Rutile Electron Extraction Layer Enables Low-Temperature Solution Processed Perovskite Photovoltaics with 13.7% Efficiency
journal, April 2014

  • Yella, Aswani; Heiniger, Leo-Philipp; Gao, Peng
  • Nano Letters, Vol. 14, Issue 5, p. 2591-2596
  • DOI: 10.1021/nl500399m

Titanium oxide thin films for NH3 monitoring: Structural and physical characterizations
journal, July 1997

  • Manno, D.; Micocci, G.; Rella, R.
  • Journal of Applied Physics, Vol. 82, Issue 1
  • DOI: 10.1063/1.365848

Gallium-doped zinc oxide films as transparent electrodes for organic solar cell applications
journal, July 2007

  • Bhosle, V.; Prater, J. T.; Yang, Fan
  • Journal of Applied Physics, Vol. 102, Issue 2
  • DOI: 10.1063/1.2750410

Transmission electron microscopy studies of atomic layer deposition TiO2 films grown on silicon
journal, September 2003

Inverted Colloidal Quantum Dot Solar Cells
journal, February 2014

  • Kim, Gi-Hwan; Walker, Bright; Kim, Hak-Beom
  • Advanced Materials, Vol. 26, Issue 20
  • DOI: 10.1002/adma.201305583

Influence of structure development on atomic layer deposition of TiO2 thin films
journal, September 2001

Electrical and Optical Properties of ZnO Processed by Atomic Layer Deposition in Inverted Polymer Solar Cells
journal, October 2010

  • Cheun, Hyeunseok; Fuentes-Hernandez, Canek; Zhou, Yinhua
  • The Journal of Physical Chemistry C, Vol. 114, Issue 48
  • DOI: 10.1021/jp106641j

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

Highly Photoactive Titanyl Phthalocyanine Polymorphs as Textured Donor Layers in Organic Solar Cells
journal, September 2011

  • Placencia, Diogenes; Wang, Weining; Gantz, Jeremy
  • The Journal of Physical Chemistry C, Vol. 115, Issue 38
  • DOI: 10.1021/jp2052085

Electrical and optical properties of TiO 2 thin films prepared by plasma-enhanced atomic layer deposition : Electrical and optical properties of TiO
journal, October 2013

  • Dang, Van-Son; Parala, Harish; Kim, Jin Hyun
  • physica status solidi (a), Vol. 211, Issue 2
  • DOI: 10.1002/pssa.201330115

Polymer Photovoltaic Cells: Enhanced Efficiencies via a Network of Internal Donor-Acceptor Heterojunctions
journal, December 1995

2.5% efficient organic plastic solar cells
journal, February 2001

  • Shaheen, Sean E.; Brabec, Christoph J.; Sariciftci, N. Serdar
  • Applied Physics Letters, Vol. 78, Issue 6, p. 841-843
  • DOI: 10.1063/1.1345834

Stability/degradation of polymer solar cells
journal, July 2008

  • Jørgensen, Mikkel; Norrman, Kion; Krebs, Frederik C.
  • Solar Energy Materials and Solar Cells, Vol. 92, Issue 7, p. 686-714
  • DOI: 10.1016/j.solmat.2008.01.005

Atomic Layer Deposition: An Overview
journal, January 2010

  • George, Steven M.
  • Chemical Reviews, Vol. 110, Issue 1, p. 111-131
  • DOI: 10.1021/cr900056b

Oriented Growth of Al2O3:ZnO Nanolaminates for Use as Electron-Selective Electrodes in Inverted Polymer Solar Cells
journal, February 2012

  • Cheun, Hyeunseok; Fuentes-Hernandez, Canek; Shim, Jaewon
  • Advanced Functional Materials, Vol. 22, Issue 7
  • DOI: 10.1002/adfm.201102968

Tunnelling charge injection into a pentacene layer using dynamic-mode scanning force microscopy
journal, January 2007

Review of photovoltaic technologies
journal, June 2011

  • El Chaar, L.; lamont, L. A.; El Zein, N.
  • Renewable and Sustainable Energy Reviews, Vol. 15, Issue 5
  • DOI: 10.1016/j.rser.2011.01.004

Increasing the Fill Factor of Inverted P3HT:PCBM Solar Cells Through Surface Modification of Al-Doped ZnO via Phosphonic Acid-Anchored C60 SAMs
journal, March 2012

  • Stubhan, Tobias; Salinas, Michael; Ebel, Alexander
  • Advanced Energy Materials, Vol. 2, Issue 5
  • DOI: 10.1002/aenm.201100668

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

Simultaneous Enhancement of Open-Circuit Voltage, Short-Circuit Current Density, and Fill Factor in Polymer Solar Cells
journal, September 2011

  • He, Zhicai; Zhong, Chengmei; Huang, Xun
  • Advanced Materials, Vol. 23, Issue 40, p. 4636-4643
  • DOI: 10.1002/adma.201103006

Interface materials for organic solar cells
journal, January 2010

  • Steim, Roland; Kogler, F. René; Brabec, Christoph J.
  • Journal of Materials Chemistry, Vol. 20, Issue 13, p. 2499-2512
  • DOI: 10.1039/b921624c

Growth Kinetics and Crystallization Behavior of TiO[sub 2] Films Prepared by Plasma Enhanced Atomic Layer Deposition
journal, January 2008

  • Xie, Qi; Musschoot, Jan; Deduytsche, Davy
  • Journal of The Electrochemical Society, Vol. 155, Issue 9
  • DOI: 10.1149/1.2955724

Phosphonic Acid Modification of Indium−Tin Oxide Electrodes: Combined XPS/UPS/Contact Angle Studies
journal, April 2008

  • Paniagua, Sergio A.; Hotchkiss, Peter J.; Jones, Simon C.
  • The Journal of Physical Chemistry C, Vol. 112, Issue 21
  • DOI: 10.1021/jp710893k

Visible photoelectrochemical water splitting into H 2 and O 2 in a dye-sensitized photoelectrosynthesis cell
journal, April 2015

  • Alibabaei, Leila; Sherman, Benjamin D.; Norris, Michael R.
  • Proceedings of the National Academy of Sciences, Vol. 112, Issue 19
  • DOI: 10.1073/pnas.1506111112

Improving the stability of atomic layer deposited alumina films in aqueous environments with metal oxide capping layers
journal, February 2013

10.2% Power Conversion Efficiency Polymer Tandem Solar Cells Consisting of Two Identical Sub-Cells
journal, May 2013

Electrical properties of TiO2 thin films formed on self-assembled organic monolayers on silicon
journal, March 1998

  • Shin, Hyunjung; De Guire, Mark R.; Heuer, Arthur H.
  • Journal of Applied Physics, Vol. 83, Issue 6
  • DOI: 10.1063/1.367132

S-shaped current-voltage characteristics of organic solar devices
journal, September 2010

Energy Level Alignment and Interfacial Electronic Structures at Organic/Metal and Organic/Organic Interfaces
journal, June 1999