Flexible dye solar cells with TiO2 nanopaper and Ti back contact electrodes

Abstract

Flexible dye solar cells (F-DSCs) have attracted great attention because of their low cost, flexibility and lightweight, and their advantages for wearable electronic devices and other applications. We propose here a novel structure of F-DSCs using flexible TiO2 nanopapers as substrates and Ti back contact electrodes(Ti BCE) as electron collection electrodes. By combining the high-temperature hydrothermal nanowire synthesis with conventional paper preparation, TiO2 nanopapers (long nanowire TiO2 free-standing membranes) with good mechanical strength and flexibility were prepared. This TiO2 nanopapers from pure long inorganic nanowires, can be used as an ideal flexible substrate for Ti BCE and nanocrystalline TiO2 films, because they retain their excellent mechanical strength and flexibility at high temperatures. The PCE of F-DSCs with TiO2 nanopaper substrate and the porous Ti BCE reached 4.38% under AM 1.5G and 100 mW cm−2 simulated solar irradiation. The F-DSCs remained stable after 100 bending tests at 16 mm bending radius.

Keywords

• Dye solar cell
• TiO2 nanopaper
• Ti back contact electrode
• Hydrothermal
• Flexible