Effects of gas blowing condition on formation of mixed halide perovskite layer on organic scaffolds

Perovskite solar cells are promising for realizing high power conversion efficiency (PCE) with low manufacturing costs, but efficient coating methods are needed for commercialization. Here, a gas blowing method was used to fabricate perovskite solar cells and was found to create a smooth perovskite layer and to prevent voids in large-area cells, when organic materials were used as scaffolds for forming the perovskite. A PCE of 13% in a 1 cm 2 active area is achieved by tuning the band-gap energy of MAPbX 3 via substitution of Br for I ions in X sites. Incorporation of a poly(3,4-ethylenedioxythiophene) hole transport layer with a higher work function increased the open circuit voltage of the solar cells. All layers of the cells were fabricated at low temperatures (<140 °C), which makes it possible to incorporate a polymer substrate for producing flexible solar cells and high-throughput fabrication.