Unraveling the relationship between the phenethylammonium-induced 2D phase on the perovskite surface and inverted wide bandgap perovskite solar cell performance

We studied the impact of phenethylammonium chloride on PIN-structured wide bandgap perovskite solar cells. Elimination of the 2D phase results in a champion efficiency of 20.61% and a V OC loss of only 410 mV with hysteresis-free J–V curves.