Efficiency enhancement in Dye Sensitized Solar Cells by light scattering in photoanode with TiO2 nanotubes

Abstract

The effect of incorporating a composite double layered structure of photoanode, based on hydrothermally synthesized TiO2 nanotubes (TNT) as the light scattering layer, on the efficiency enhancement of dye sensitized solar cells (DSSCs) is reported. Device performances comprising this novel photoanode is compared with the DSSCs fabricated with the conventional type of photoanodes without TNT. Further enhancement in the device performances is obtained with the post treatment of the photoanode with TiCl4. The DSSC with post treated two layered composite photoanode showed an overall efficiency of 8.31% with a short circuit photocurrent density (Jsc ) of 16.91 mA cm−2 and 783.4 mV of an open circuit voltage (V oc) under the irradiance of 1000 W m−2. In comparison, the reference DSSC with a post treated photoanode having the same thickness showed 7.62% efficiency while delivering a Jsc of 15.60 mA cm−2 with 773.5 mV. The remarkable enhancement in the device performance is achieved due the employment of this double-layered novel photoanode in the DSSCs. However, lower electron life time is observed in the DSSCs with TNT layer suggesting that, rate of electron recombination is higher in the DSSCs with this novel photoanode, although the overall efficiency of the present device and the net result due to the enhanced light harvesting and scattering effect may still be regarded as an favorable alternative for certain applications.