Radical Form of PbI2: A New Defect Passivator for Efficient Perovskite Solar Cells

PbI2 is a commonly used passivator for defect passivation in perovskite solar cells (PSCs). However, the poor conductivity nature of PbI2 may limit the further improvement of device performance. Here, we report a radical form of PbI2 with high conductivity to passivate defects for efficient PSCs through a combination of N,N,N',N'-tetramethylbenzidine (TMB). When PbI2 is combined with TMB, 4 orders of magnitude higher conductivity will be achieved owing to the formation of a TMB-PbI2 radical. As a result, the device performance is impressively increased from 20.48 to 22.63%. In addition, the device stability is also greatly improved and 95% of the initial efficiency is retained after aging at 85 degrees C for 600 h.

Automated summary

By combining PbI2 with TMB to form the TMB-PbI2 radical, the conductivity is increased by 4 orders of magnitude, leading to an impressive increase in device performance from 20.48% to 22.63%. Moreover, the device stability is greatly improved, with 95% of the initial efficiency retained after aging at 85 degrees C for 600 hours.