CH3NH3PbI3 converted from reactive magnetron sputtered PbO for large area perovskite solar cells

Abstract Adopting DC reactive magnetron sputtering technique, PbO film was fabricated on FTO-glass substrate coated with a nanocrystalline rutile titania (NRT) by using a pure metallic lead target in an Ar/O 2 mixture. Then the as-prepared PbO film was converted to CH 3 NH 3 PbI 3 through the sequential reactions occurred in isopropanol solution of CH 3 NH 3 I. The as-prepared perovskite film exhibits a surface morphology of high uniformity and good coverage over a large scale; the crystal grains reach the size of up to 600 nm, which is beneficial for enhancing light absorption and decreasing grain boundary. The solar cells with a structure of FTO/NRT/CH 3 NH 3 PbI 3 /Spiro-MeOTAD/Au were fabricated, where NRT was employed as the contact layer of the photovoltaic devices. Our champion cells with active area of 0.09 cm 2 and 1.07 cm 2 achieve the highest power conversion efficiency of 14.1% and 10.7%, respectively, under the standard AM 1.5 conditions. The present approach is competent for the fabrication of large area perovskite solar cells with the advantages of easy control, cost-saving, and less use of toxic reagents, and thus with potential applications.