Fabrication of Quantum Dot-Sensitized Solar Cells Based on a Transparent TiO₂ Film with Reasonable Load Resistance Design

While transparent photoanodes are highly desired for smart energy devices, their performance is still far from expectation. In the present work, a transparent TiO2 film was prepared using a two-step spin-coating method, which served as photoanodes of quantum dot-sensitized solar cells (QDSSCs). A porous TiO2 photoanode prepared by P25 was also fabricated for comparison. Compared with the porous TiO2 photoanode, QDSSCs based on the transparent TiO2 film showed an obviously declined short-circuit current density (Jsc) but greatly improved fill factor (54.3%), resulting in a larger power conversion efficiency (4.32%). The reason is due to the decreased series resistance and increased shunt resistance of solar cells based on the transparent TiO2 photoanode, which is consistent with the requirement of solar cells to load resistance. The present work proves that the transparent TiO2 film has great potential in the field of transparent solar cells