Enhancing Power Conversion Efficiency of Dye-Sensitized Solar Cell Using TiO2-MWCNT Composite Photoanodes

Abstract

The aim of this work is to improve the power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs) using composite films consisting of titanium oxide (TiO2) nanoparticles and multiwalled carbon nanotubes (MWCNTs). A transmission electron microscope (TEM) was used to confirm the dispersion of carbon nanotubes (CNTs) in TiO2. Composite photoanode-based solar cells were characterized by UV-Visible absorption spectroscopy, photocurrent-voltage (I-V) characteristics, and electrochemical impedance spectroscopy. It was found that the PCE (?c) of DSSCs strongly depends on the concentration of CNTs in the nanocomposite films. The solar cell assembled with photoanode containing 0.06% MWCNTs shows the highest efficiency of 5.25%, which is 46% greater than unmodified photoanode. The density functional theory (DFT) quantum modeling technique was used to compute the band gap of TiO2 and CNT-TiO2 clusters.