Enhanced photoconversion efficiency of all-flexible dye-sensitized solar cells based on a Ti substrate with TiO₂ nanoforest underlayer.

An easily prepared TiO2 nanoforest underlayer improves the photovoltaic performance of Ti substrate-based dye-sensitized solar cells (DSSCs). A high photoconversion efficiency of 8.46% is reached, which is almost 2.5 times that of the DSSCs without surface treatment of the flexible substrates. The nanoforest underlayer increases both the surface roughness of the substrate and the electrical contact between the Ti substrate and the screen-printed TiO2 nanoparticles.