Synthesis of ZnO/SnO2 composite films for solar cells

Abstract Metal oxide films are synthesized as semiconductors in solar cells. Zinc oxide is often used as an electrode in solar cells due to its good photoconversion properties. These same properties can be tuned by adding other elements to the main zinc oxide matrix. Dye sensitized solar cells represent the third generation of solar cells, with advantages such as flexibility and simple set up. Dye solar cells convert energy, based on the electron transport between dye, photoanode and counter electrode. Zinc oxide films were synthesized by adding tin oxide at different percentages, 5, 10 and 15%, and tested in dye cells. The zinc oxide films with 15% tin oxide presented higher photovoltaic efficiency, around 0.96%, current density of 2.98 mA/cm 2 and open voltage of 0.61 V. At 10% tin oxide, the values were 0.54 FF and 2.32 mA/cm 2 . And at 5%, open voltage was 0.64 V and 1.53 mA/cm 2 of current. All the films had band gap around 3.25 eV, lower than the average zinc oxide film around 3.31 eV; thickness ranging from 1 to 2.4 μm, with crystallite size between 28 and 80 nm and dislocation densities were 12.2 × 10 14 ; 3. x10 14 and 1.5 × 10 14 (lines.m − 2 ), respectively for 5, 10 and 15% tin/zinc films.