PEAI - Indeed an Effective Synergistic Modification Material to Improve All Perovskite Tandem Solar Cell Efficiency to Nearly 27%

Abstract

Here, we propose a double-sided passivation strategy by introducing phenylethyl ammonium iodide (PEAI) at the top and bottom wide bandgap perovskite interfaces. We elucidated the subtle chemical interaction between PEAI, perovskite and NiOx through theory and experiment. The result proves that this chemical interaction can further improve the quality of the perovskite film, thereby reducing the bulk nonradiative recombination of the device and strengthening interface connections. In addition, the reduced interface defects also lead to reduced non-radiative recombination at the interface. Ultimately, single-junction wide bandgap PSCs achieved a high PCE of 16.5%, while device stability improved. The PEAI-based all-perovskite tandem solar cell also got a champion PCE of 26.81%.