Slot-die coated methylammonium-free perovskite solar cells with 18% efficiency

One of the major bottlenecks of perovskite photovoltaic modules fabrication is the homogeneous deposition of perovskite material on large-area substrates. Here, we show that slot-die coating technique combined with synergistic gas quenching and substrate heating can produce compact, homogenous and reproducible Cs0.16FA0.84Pb(I0·88Br0.12)3 perovskite films. We demonstrate the fabrication of perovskite solar cells (PSCs) in a planar (n-i-p) device configuration and attain power conversion efficiency (PCE) of 18% over 0.09 cm2 device active area. The versatility of this crystallization strategy, which eliminates the need for complex solvents or additive engineering, was studied using planar SnO2- and TiO2-coated FTO substrates. Our study provides greater insights into achieving controlled coating and homogeneous crystallization of perovskite films over large-area substrates (~10 × 10 cm2) necessary for the commercialization of this technology.