Intermolecular interaction assisted fabrication of Dion-Jacobson perovskite film with promoted photovoltaic property

Two dimensional (2D) perovskite solar cells have attracted lots of attentions due to the better stability than their three dimensional counterparts. The interaction between the spacer cations of the 2D perovskite has great impact on the quality of the film. While, as to 2D Dion-Jacobson (DJ) perovskites, few studies are reported on this topic. Herein, we choose 2,2′-disulfanediylbis(ethan-1-ammonium) (DSDEA) with SS unit as spacer cation to introduce intermolecular interaction, which promotes the crystallinity and oriented growth of the quasi-2D DJ perovskite film, and the charge transport. The device with structure of ITO/PEDOT:PSS/(DSDEA)MA4Pb5I16/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM)/bathocuproine (BCP)/Ag reaches a PCE of 14.12 %, much higher than 1,6-hexamethylenediamonium-based devices. The unsealed device retains about 87 % of its original PCE in the air atmosphere with humidity of 45 ± 5 % after 35 days’ storage.