Abstract
Methylammonium Lead Iodide perovskite (MAPbI3) is today considered the most promising component for highly efficient third generation solar cells. However, the lifetime of the solar devices is strongly affected by the stability of the MAPbI3 films towards humidity, UV irradiation and temperature. The search for efficient protective additives to be used for building up composite perovskite films with enhanced stability is a topic of great interest in the scientific community. In the present paper we have applied a layered zirconium phosphate-phosphonate based on N,N-phosphonomethyl glycine, exfoliated in thin nanosheets (NS), as additive for the stabilization of MAPbI3 crystalline films towards humidity, UV-irradiation and temperature changes. Notably, the additive resulted extremely efficient to prevent degradation of the perovskite film, preserving the optical and structural properties and avoiding the phase transitions normally observed due to temperature increase.