Efficient defect passivation for high performance perovskite solar cell by adding alizarin red S

Planar perovskite solar cells (PSCs) have excellent photoelectric properties and show great commercialization potential. However, there are a lot of crystal defects in the perovskite films prepared by solution method, which reduces the development process of solar cells. In this work, alizarin red s (ARS) was doped into MAPbI3 films to passivate the defect. It was shown that the addition of ARS increased the quality of perovskite film and doped perovskite film exhibited improved light absorption. In addition, it was found that there was a strong interaction between ARS and perovskite, which reduced the density of defect states. The results showed that the passivated perovskite device had improved PL intensity, increased carrier lifetimes and reduced charge recombination. After passivation, the device obtained a higher open-circuit voltage (VOC) of 1.103 V where the control device was 1.055 V, and the best power conversion efficiency (PCE) of the doped device was 18.82%, which is 11.36% higher than that of the control device of 16.90%.