Antisolvent Additive Engineering Containing Dual-Function Additive for Triple-Cation p–i–n Perovskite Solar Cells with over 20% PCE

In this work, we attempt to improve the quality of the perovskite film using a functional additive in the perovskite antisolvent, which is known as antisolvent additive engineering (AAE). An AAE additive, 2-hydroxyethyl acrylate (HEA), that includes −OH and C═O functional groups is introduced into the antisolvent. Its effect on the perovskite film and devices is then systematically studied. Comprehensive analyses including cell performance, carrier transport dynamics, and perovskite surface and morphology measurements were performed to prove that this HEA-based AAE leads to better perovskite films with a larger grain size and fewer perovskite defects and also to prove that this AAE approach is a promising way to obtain high-quality perovskite and corresponding high-efficiency perovskite solar cells. As a result, this facile AAE with HEA obtained a maximum power conversion efficiency (PCE) of 20.46% and showed better stability, maintaining over 61% of its initial PCE after 96 days under ambient air conditions.