Browsing by Author "Kyaw A.K.K."

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Demonstration of the portability of porous microstructure architecture to indium-doped ZnO electron selective layer for enhanced light scattering in inverted organic photovoltaics
    (Springer New York LLC, 2016) Nirmal A.; Kyaw A.K.K.; Sun, X.; Demir, Hilmi Volkan
    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.
  • Thumbnail Image
    ItemOpen Access
    Light trapping in inverted organic photovoltaics with nanoimprinted ZnO photonic crystals
    (IEEE Electron Devices Society, 2017) Nirmal A.; Kyaw A.K.K.; Jianxiong, W.; Dev K.; Sun, X.; Demir, Hilmi Volkan
    Zinc oxide photonic crystal (ZnO PC) formed via facile nanoimprinting was employed on the ZnO electron selective layer of inverted organic photovoltaics (OPV). Optimized inverted OPV fabricated with these highly ordered periodic structures provided effective light trapping, which resulted in increased incident light absorption in the active layer. Consequently, OPVs with the ZnO PC layers show a 23% current density improvement compared with OPVs with planar ZnO layer. Finite-difference time-domain simulation studies show that the electric field intensity is significantly higher in the active layer for devices with ZnO PC structures in comparison with reference devices with planar ZnO electron selective layer. Nanoimprinted ZnO PC is, thus, a viable method for light absorption and efficiency enhancement in OPVs. � 2011-2012 IEEE.