Preparation of methylammonium lead iodide (CH₃NH₃PbI₃) thin film perovskite solar cells by chemical vapor deposition using methylamine gas (CH₃NH₂) and hydrogen iodide gas

An upscalable chemical vapor deposition setup has been built‐up and employed in producing methylammonium lead iodide (MAPI) thin film perovskite solar cells, leading to a maximum efficiency of 12.9%. The method makes use of methylamine gas and hydrogen iodide gas to transform a predeposited layer of lead(II)iodide (PbI₂) into MAPI. Although the reaction mechanism includes the intermediate phases lead oxide (PbO) and lead hydroxide (Pb(OH)₂), indicated at least on the surface of the samples by XPS, neither species could be observed in XRD measurements of the stepwise reaction, which show a mixture of highly oriented cubic and tetragonal MAPI perovskite lattice systems.