Research On Invered Plannar Perovskite Solar Cells With PTAA As Hole Transport Layer

Up to now,planar heterojunction perovskite solar cells with p-i-n type device structure have attracted extensive attention by scientific researchers,due to their hysteresis-free behavior,low preparation temperature,simple fabrication process,and easy implementation of flexibility.The hole transport material is a crucial layer in the perovskite solar cell,and demands to have good conductivity,high hole mobility,matching energy level and good film formation.Poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine](PTAA)is a typical hole-transport material for planar heterojunction perovskite solar cells with p-i-n device structure.When It was used as a hole transport layer in perovskite solar cell,good device performance was achieved.However,as an organic semiconductor,PTAA also suffer from poor conductivity.The main research contents of this dissertation are to find better p-type dopants or provide a simple and effective processing method to improve the hole transport property of PTAA.In this work,we first modify the PTAA hole transport material using strong Lewis acid tris(pentafluorophenyl)borane(BCF)as the p-type dopant.The hole transport property of PTAA was improved a lot.After doping,the conductivity of PTAA was increased by two orders magnitude.What's more,we found that the conductivity of PTAA can be further improved by irradiation treatment to the BCF doped PTAA solution.This paper systematically studied the mechanism the promotion of hole transport property of PTAA by BCF doping and irradiation treatment.UV-Vis absorption spectroscopy,nuclear magnetic resonance,FTIR,ESR and conductivity measurment have been carried out.BCF has a strong ability to attract electrons,electron transfer complex can be easily to form between PTAA and BCF.The formation of the electron transfer complex greatly increases the hole charge carrier concentration in the PTAA film.and the maximum photoelectric conversion efficiency reached 18.50%,with JSC 22.37 m A/cm2,VOC 1.06 V,and FF 0.78,which is 11.2% higher than that of the device without BCF.When 8% BCF doped PTAA solution is irradiated by light for 1-3 min,the device performance of the corresponding perovskite solar cells can be further improved.The maximum photoelectric conversion efficiency is 19.07%,with JSC 23.17 m A/cm2,VOC 1.04.V,and FF 0.79.This work provides a simple and effective method to improve the hole transport peroperty of the triphenylamine hole transport materials,and the photoelectric conversion efficiency of the corresponding planar heterojunction perovskite solar cells were greatly improved.