Enhanced Device Performances of MAFACsPb(I<sub><i>x</i></sub>Br<sub>1–<i>x</i></sub>) Perovskite Solar Cells with Dual-Functional 2-Chloroethyl Acrylate Additives
Se-Phin Cho, Sung‐Nam Kwon, Mi‐Jung Choi, You‐Hyun Seo, Seok‐Soon Kim, Seok‐In Na
Abstract
Perovskite photovoltaics (PePVs) tend to suffer from a high density of defects that restrict the device in terms of performances and stability. Therefore, defect passivation and film-quality improvement of perovskite active layers are crucial for high-performance PePVs. In this work, 2-chloroethyl acrylate (CEA) with C═O and −Cl groups in Cs0.175FA0.750MA0.075Pb (I0.880Br0.120) precursor solutions is introduced as a novel bifunctional additive to act as both a defect passivator and perovskite-growth controller. With the aid of CEA, the perovskite crystallinity and average grain size are improved, and perovskite defects are effectively reduced, thus increasing the representative efficiency (PCE = 19.32%). PePVs with CEA also maintain their initial efficiency of 85% even after about 500 h under air conditions with a humidity of 40 ± 5%. As a result, this study proves that the novel additive CEA can produce higher PePV efficiency and more stable devices.