Inkjet-Printed Mesoporous TiO2 and Perovskite Layers for High Efficiency Perovskite Solar Cells

Perovskite solar cells with mesoporous TiO2 electron transport layers have previously reached >22 % efficiency at the laboratory scale (10 cm2. Perovskite solar cells with printed and pristine (un-doped) inkjet-printed TiO2 layers yielded efficiencies of 18.29 %, which were found to outperform cells made with spin-coated and pristine TiO2 layers (16.91 %). When a quadruple-cation perovskite absorber containing Cs, formamidinium, methylammonium, and guanidinium was deposited by inkjet-printing onto the inkjet-printed TiO2 layer, nearly 12 % average efficiency was reached, with the champion cell reaching 14.11 %. This absorber exhibited higher efficiency and stability than did inkjet-printed MAPbI3 films deposited on the inkjet-printed TiO2 film.