Large Area Perovskite Solar Cell via Two-step Ultrasonic Spray Deposition

We report a controllable two-step deposition method for fabricating perovskite solar cells. The perovskite light absorption layers were prepared by the reaction of spin-coated PbI
₂
and spray-coated CH
₃
NH
₃
I. The CH
₃
NH
₃
I precursor solution is spray-coated under ambient atmosphere, which gives a better control of the perovskite morphology and a completed reaction. Using this method, we achieve a PCE of 11.4% at a 0.04 cm
²
device area, and 8.8% at a 1.16cm
²
device area.