Introducing paired electric dipole layers for efficient and reproducible perovskite solar cells

Abstract

Elimination of charge trapping at defects is highly challenging for poly-crystalline organometal halide perovskites. Here, we report a new architecture for reinforcing the built-in electric field (E-in) across the photoactive layer with a pair of strong electric dipole layers (EDLs). The paired EDLs significantly intensify the E-in across the perovskite layer, resulting in suppressed charge trapping of photogenerated charges. As a result, our low-temperature processed P-I-N planar PeSC devices using the paired EDLs exhibit a higher power conversion efficiency (eta(max) similar to 19.4%) and a smaller device-to-device variation with a standard deviation (S. D.) of 0.70%, which far surpass those (eta(max) similar to 17.8%, S.D. similar to 1.1%) of the devices with typical charge transport layers.