Efficient All-Inorganic CsPbBr <sub/>3</sub> Perovskite Solar Cells by Using CdS/CdSe/CdS Quantum Dots as Intermediate Layers

摘要： Highly e?cient all-inorganic perovskite solar cells require a fast charge transfer from CsPbBr3 to TiO2 to reduce the recombination from trap states. Herein, we insert a CdS/CdSe/CdS quantum dot (QD) layer between the TiO2 and CsPbBr3 layers to fabricate all-inorganic perovskite solar cells. By tuning the thicknesses of the CdSe layer of CdS/CdSe/CdS QDs, the conduction band (CB) levels can be adjusted to -3.72~-3.87 eV. After inserting the QD intermediate layer, the energy o?set between the CB of TiO2 and CsPbBr3 is reduced, thus leading to a charge transfer rate boost from 0:040 × 109 to 0:059 × 109 s?1. The power conversion e?ciency (PCE) of the solar cell with QD intermediate layer achieves 8.64%, which is 20% higher than its counterpart without QDs.