Research On Improving The Performance Of Polymer And Perovskite Solar Cells Through Interface Regulation

Organic and perovskite solar cells,as the hotspots of current research,have many good characteristics,such as higher light energy conversion efficiency,simple manufacturing processes,low manufacturing costs,and broad application prospects,but higher efficient batteries have always been the subject of research.In this paper,we have mainly studied a simple interface control solvent method,which is applied to organic and perovskite solar cells to improve efficiency,as follows:1.Using a mixed solvent of acid and alcohol,acting on the organic active layers P3HT:PC₆₁BM and P3HT:ICBA,respectively.Compared with the device using Ca as the cathode interface modification layer,in the P3HT:PC₆₁BM system,the mixed solvent exhibits 3.98%of the energy conversion efficiency,the Ca comparison device of the same group is only 3.63%.We also used a mixed solvent to act on the P3HT:ICBA system.The device spin-coated with the mixed solvent had an efficiency of 5.75%,while the Ca comparison device in the same group had only 5.22%.We compared these two sets of experiments and found that the devices treated with mixed solvents had higher short-circuit current density and fill factor.So we carried out a series of characterizations from the perspective of the surface morphology and surface chemical composition of the active layer,and studied the mechanism.We found that the acid in the mixed solvent will cause the relative movement of the two phases in the active layer,and also introduce hydrogen bonding.These two effects will increase the current of the device.The methanol in the mixed solvent can passivate the trap state on the surface of the device,and at the same time,it can change the surface potential of the active layer,thereby improving the two performance parameters of voltage and fill factor.When two solvents are mixed and the effect is superimposed,making the mixed solvent effect excellent for Ca-modified devices.2.The mixed solvent was applied to the inorganic perovskite solar cell based on CsPbI₂Br,and the original PTAA modified layer was further improved.We found that compared to the 11.46%efficiency of the pristine,the efficiency of the processed device was increased to 13.36%.In addition,the hysteresis has dropped from 77.6%to 33.8%.After a series of characterizations,we believe that the acetic acid in the mixed solvent can interact with the Lewis base in PTAA to form N radicals,thereby improving the device mobility;The alcohol in the mixed solvent can passivate the defects on the surface of PTAA,so that the cracks on the surface of PTAA are reduced,which is more conducive to the extraction and transmission of carrier.The efficiency is improved.