Two-dimensional benzylammonium based perovskites incorporated with hexamethylendiammonium for solar cell application

This paper introduced new two dimensional (2D) benzylammonium (BZA) based perovskites incoorperated with hexamethylendiammonium (HDA) for solar cell application. The influence of HDA additive on the cystallinity, morphology, photoelectrical properties and stability of (BZA) 2 (MA) 2 Pb 3 I 10 (MA = CH 3 NH 3 + ) were investigated. Results showed that the incorporation of diamine cation into the Ruddlesden-Popper perovskite (BZA) 2 (MA) 2 Pb 3 I 10 was useful in improving its phase purity, surface roughness , conductivity and performances in perovskite solar cells . The 2D (BZA) 2 (MA) 2 Pb 3 I 10 perovskite films with HDA incorpation showed much enhanced moisture stability than its 3D perovskite counterpart MAPbI 3 . By optimizing the HDA concetration, an efficiency of 3.33% was obtained for mesostrucured (BZA) 2 (MA) 2 Pb 3 I 10 based perovskite cell, which is more than a time higher than that of (BZA) 2 (MA) 2 Pb 3 I 10 without HDA (1.59%). Our work emphasized the significance of material purity and quality for BZA based perovskite solar cells, demonstrating the validity of mixed amine cations in improving their photovoltaic performance .