Highly efficient and stable perovskite solar cells based on E-beam evaporated SnO2 and rational interface defects passivation

Owing to the significant roles in balancing carrier transport, bandgap alignment, and perovskite crystallization, realizing high-quality electron transport layers (ETLs) and their effective electronic contact with the perovskite photoactive layer is crucial for future commercialization of perovskite solar cells (PSCs). Here, a high-quality SnO 2 ETL is firstly deposited at room temperature via the low-cost electron beam evaporation (E-beam) technology to help achieve an impressive PCE of 18.88% for rigid PSCs and a PCE of 15.73% for flexible devices. Then we introduced a novel passivating ligand molecule, 11 Maleimidoundecanoic acids (11MA), to help induce functional defects passivation at the interface of SnO 2 /Perovskite to coordinate with Pb 2+ in perovskite and Sn 4+ in SnO 2 via the functional groups (-C = O, -COOH). As a result, 11MA could help achieve the best PCE of 20.94% with negligible hysteresis for rigid devices. Also, doping 11MA in the perovskite photoactive layer further enhanced the PCE to 22.08% with much improved 2000 hours ambient stabilities. Finally, we fabricated different large-area rigid devices (10, 40, 100, and 600 mm 2 ) toward speeding up the commercialization of PSCs by industrial E-beam technology and rational defects passivation strategies.