Perovskite Solar Cells toward Eco-Friendly Printing
(a) Pictures of SnO2 in H2O solvent, perovskite precursors in 1,3-dimethyl-2-imidazolidinone (DMI) solvent, and Spiro-OMeTAD in ethyl acetate (EA) solvent. (b) Perovskite precursors and molecular structure of DMI and EA solvents. (c) Schematic illustration of blade coating for perovskite films. (d) Photograph of large-area () MAPbI3 films fabricated using the blade coating method. (e) Photographs (top) and scanning electron microscopy (SEM) images (bottom) of SnO2, SnO2/MAPbI3, and SnO2/MAPbI3/Spiro-OMeTAD films. (f) Cross-sectional SEM image of a complete device.