Figure 4From: Transparent TiO2 nanotube array photoelectrodes prepared via two-step anodization (a) Normalized transmittance of transparent TiO 2 NT arrays (without dye adsorption) with various thicknesses, where the inset shows the normalized absorption spectra only by the dye molecules adsorbed on the NT surfaces, and (b) Normalized IPCE spectra of DSSCs composed of transparent TiO 2 NT arrays with different thicknesses. Back to article page