PbS colloidal quantum dots as an effective hole transporter for planar heterojunction perovskite solar cells

Here, we applied colloidal quantum dots (CQDs) as an effective p-type hole-transporting material (HTM) for planar heterojunction perovskite solar cells. By tuning the size of PbS CQDs, we engineered the energy alignment of the valence and conduction band of this new HTM with the perovskite light harvester and achieved conversion efficiencies up to 7.5%. Absorption of PbS CQDs also extends the absorption spectrum of perovskite solar cells into the infrared region.