Lead Halide Residue as a Source of Light Induced Reversible Defects in Hybrid Perovskite Layers and Solar Cells


A clear signature of deep defects in at least the 1 ppm range is observed by low absorptance photocurrent spectroscopy. An efficiency drop, together with the defects, appears after minutes-long blue illumination and disappears after 1 h or more in the dark. This is caused by the lead halide residual phase inherently present in material prepared by the two-step method. Lead halide decomposes into metallic lead and mobile iodine, which diffuses into the perovskite, producing interstitial defects.

Defects in CH3NH3PbI3 due to illumination observed by FTPS below absorption edge and effect on efficiency


Contact: Jakub Holovský
Collaborating institutions: CTU Faculty of Electrical Engineering