Enhanced Performance of Perovskite Solar Cells Loaded with Iodine-Rich CsPbI₃ Quantum Dots

To pursue practical applications of perovskite solar cells (PSCs), while the power conversion efficiencies (PCEs) are continuously pushed up, defect passivation of the metal halide perovskite layer is considered an efficacious method for improving the efficiency and stability of the devices. Herein, we proposed incorporating iodine-rich CsPbI3 quantum dots (QDs) in the halide perovskite film to improve the photovoltaic performance of PSCs. Using the modified QDs enabled the reduction of the nonradiative recombination centers by passivating iodide vacancies and optimization of the energy alignment near to the perovskite/hole transport material interface. Finally, high-performance planar PSCs with an efficiency exceeding 22% and higher long-term stability (over 91% of its initial PCE after 39 days) were achieved.