Enhancing the photovoltaic responses of MAPbI3 poly-crystalline perovskite films via adjusting the properties of PEDOT:PSS hole transport material with a low-polarity solvent treatment process

The surface and electrical characteristics of the poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) materials are manipulated using a low -polarity solvent treatment process, which influences the formation and nucleation/crystal growth process of the CH3NH3PbI3 (MAPbI3) perovskite films and thereby determining the crystal orientation and grain size. The hydrophilicity of the PEDOT:PSS composite material fabricated on the ITO/glass sample is reduced with the xylenes solvent treatment or a hexamethyldisilazane: xylenes solvent mixture treatment, which can be used to form the photo -active perovskite crystals and thereby reducing the photocurrent hysteresis of the fabricated perovskite based photovoltaic devices. It is worthwhile to mention that the non -perfectness of closed -loop in the photocurrent density -voltage curves under the forward and backward scans can be used as an indicator to assess the properties of the MAPbI3 films. Our findings can facilitate the development of perovskite based optoelectronic devices.