Improved efficiency of quantum dot-sensitized solar cells based on transparent black TiO2 modified photoanodes

Transparent TiO2 photoanodes offer promise for new solar technology due to their high light transmittance, but the persistently inadequate solar conversion efficiency continues to pose obstacles for practical application. This research utilized n-butyl titanate and black P25 TiO2 (B-P25) to construct transparent TiO2 photoanodes for quantum dot sensitized solar cells (QDSSCs). The B-P25 presents rich oxygen vacancies after reduction, along with the generation of more pore structures in the TiO2 photoanode films, facilitating the transport of photogenerated charge carriers in the photoanode films. Therefore, the photoelectric conversion efficiency (PCE) is significantly enhanced from 1.77% to 5.04%, with an increase in the short-circuit current density in the J–V curve from 8.10 to 17.67 mA cm−2. This study demonstrates that B-P25 prepared using the reduction method can effectively fabricate photoanodes with high photovoltaic performance, which improves the optical properties and solar cell efficiency of QDSSCs.