Journal of Sol-Gel Science and Technology

, Volume 78, Issue 3, pp 613–620 | Cite as

Demonstration of the portability of porous microstructure architecture to indium-doped ZnO electron selective layer for enhanced light scattering in inverted organic photovoltaics

  • Amoolya Nirmal
  • Aung Ko Ko Kyaw
  • Xiaowei Sun
  • Hilmi Volkan DemirEmail author
Original Paper: Sol-gel and hybrid materials for optical, photonic and optoelectronic applications


We propose and demonstrate the incorporation of porous microstructures on indium-doped zinc oxide (IZO) electron selective layer in inverted organic photovoltaics (OPV). Porosity was induced in the IZO layer with the addition of polyethylene glycol (PEG) organic template at the optimal IZO/PEG ratio of 4:1. When compared to the OPV device with non-porous IZO, the device employing porous IZO showed a 16 % improvement in current density and a 13 % improvement in efficiency. This is primarily due to the increased light scattering as substantiated by the haze factor studies. This PEG assisted method of introducing microporous structure is therefore shown to be compatible with the doped interlayer and is thus a portable method of enhancing light scattering in OPV devices.

Graphical Abstract

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Indium-doped zinc oxide Sol–gel Porous Organic photovoltaics 



This work was supported by the Singapore National Research Foundation under Grant Nos. NRF-CRP-6-2010-2 and NRF-RF-2009-09, the Singapore Agency for Science, Technology and Research (A*STAR) SERC under Grant Nos. 092 101 0057 and 112 120 2009, the New Initiative Fund and Joint Singapore-German Research Projects from Nanyang Technological University, A*STAR SERC TSRP Grant (Grant #102 170 0137) and IMRE exploratory Project (Grant # IMRE/14-1C0247).


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Amoolya Nirmal
    • 1
  • Aung Ko Ko Kyaw
    • 2
  • Xiaowei Sun
    • 1
  • Hilmi Volkan Demir
    • 1
    • 3
    • 4
    • 5
    Email author
  1. 1.LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, TPI- The Photonics Institute, School of Electrical and Electronic EngineeringNanyang Technological UniversitySingaporeSingapore
  2. 2.Institute of Materials Research and EngineeringAgency for Science Technology and Research (A*STAR)SingaporeSingapore
  3. 3.School of Physical and Mathematical SciencesNanyang Technological UniversitySingaporeSingapore
  4. 4.Department of Electrical and Electronics Engineering, UNAM-National Nanotechnology Research CenterBilkent UniversityAnkaraTurkey
  5. 5.Department of Physics, UNAM-National Nanotechnology Research CenterBilkent UniversityAnkaraTurkey

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