Nano-structured CdTe, CdS and TiO2 for thin film solar cell applications

Nano-crystalline CdTe and nano-structured CdS films in crystalline, porous and fiber forms were deposited on ITO-coated glass substrates. CdTe films exhibited a typical particle size of 10 nm and a blue shift in the absorption with an effective band gap of 2.8 eV. CdS films exhibited a typical particle size of 15 nm and an effective band gap of 2.98 eV. Also, porous CdS and porous TiO2 films were deposited on plastic substrates by a self-assembly method. Typical pore sizes were 80 and 70 nm, respectively. These can be used in nano-structured solar cell configuration where the pores are filled with a suitable absorber material. Additionally, CdS fibers and nano-crystalline films of TiO2 on plastic substrates were fabricated. Typical particle size in TiO2 was 10 nm and CdS fibers were about 80 nm wide and 1.5 μm long.