Dye-sensitized solar cells based on tungsten trioxide-titanium dioxide nanotube nanocomposite photoanodes

Abstract

The effect of tungsten trioxide doping on the photovoltaic efficiency of dye-sensitized solar cells (DSSCs) with anodized TiO₂ nanotubes was investigated. Tungsten-doped TiO₂ nanotubes with different amounts of tungsten were obtained directly by the electrochemical anodizing of titanium in a single-step process using sodium tungstate as the tungsten source. Nanocomposite films features were investigated by scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy and ultraviolet-visible spectroscopy. The photovoltaic efficiencies of fabricated DSSCs were characterized by a solar cell measurement system via the photocurrent-voltage (I–V) curves. It was found that the photovoltaic efficiency of DSSCs with tungsten-doped TiO₂ nanotubes (sample WT2) was improved compared to DSSCs with as-prepared TiO₂ nanotubes and WT samples fabricated using other tungsten concentrations. This improvement is ascribed to increased dye loading and photocurrent density.

Keywords:

• Dye-sensitized solar cell
• Nanocomposite
• Film
• Nanotubes
• Anodizing