Effects of hydrochloric acid treatment of TiO2 nanoparticles/nanofibers bilayer film on the photovoltaic properties of dye-sensitized solar cells

The TiO2 nanoparticles/nanofibers bilayer film has been fabricated via spin coating and electrospinning followed by calcination. The TiO2 bilayer film with-thickness of about 6.0 mu m is composed of anatase TiO2 phase. Dye-sensitized solar cells (DSSC) were assembled by hydrochloric acid (HCl) treated TiO2 film. The results of the photocurrent action spectra, electrochemical impedance spectroscopy (EIS), and I-V curves showed that each photovoltaic parameter of DSSC increased with the concentration of HCl increasing, and reached a maximum value and afterwards decreased. The maximum incident monochromatic photo-to-electron conversion efficiency (at 350 nm) and maximum overall conversion efficiency (eta) of 0.05 M HCl treated TiO2 based DSSC were enhanced to 48.0% and 4.75%, which were respectively increased by 14% and 6.3% than those of DSSC based on untreated TiO2 film. (c) 2012 Elsevier Ltd. All rights reserved.