Accelerating the Screening of Perovskite Compositions for Photovoltaic Applications through High‐Throughput Inkjet Printing

Abstract The exploration and optimization of numerous mixed perovskite compositions are causing a strong demand for high‐throughput synthesis. Nevertheless high‐throughput fabrication of perovskite films with representative film properties, which can efficiently screen the perovskite compositions for photovoltaic applications, has rarely been explored. A high‐throughput inkjet printing approach that can automatically fabricate perovskite films with various compositions with high reproducibility and high speed is developed. The automatic sequential printing of four precursors forms 25 mixed films in a fast and reproducible manner. The obtained bandgaps, photoluminescence (PL) peak positions, and PL lifetimes allow for the efficient screening of perovskite compositions for photovoltaic applications. To exemplify this concept, among 25 tested films, two compositions CH 3 NH 3 PbBr 0.75 I 2.25 (MA) and (HC(NH 2 ) 2 ) 0.75 (CH 3 NH 3 ) 0.25 PbBr 0.75 I 2.25 (FA 0.75 MA 0.25 ) with a long (237 ns) and short (49.0 ns) PL lifetime, respectively, are screened out for device investigations. As expected, the MA‐based device exhibits a much higher efficiency (19.0%) than that (15.3%) of the FA 0.75 MA 0.25 counterpart. This efficiency improvement is mainly ascribed to a smaller dark saturate current density, a lower level of energetic disorder, more efficient charge transfer and decreased charge recombination losses, which are consistent with the much longer PL lifetime in the database.