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

Abstract

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.