Preparation And Study Of Properties Of Organic Hybrid Inorganic Perovskite Solar Cells

Among the emerging photovoltaic technologies,organic and perovskite quantum dots（PQDs）solar cells have thrived on low-energy processing and extraordinary optoelectronic properties.The state-of-the-art power conversion efficiency（PCE）of single-junction organic solar cells has now exceeded 19%,and that of perovskite quantum dots solar cells（PQDSCs）has also reached 17%.The introduction of PQDs into the active layer of organic solar cells（OSCs）can increase light absorption,optimize charge transfer and energy transfer processes within the active layer,and tune the nanoscale morphology.However,there is still a lack of the revealing of operational mechanism by introducing PQDs into the mainstream high-efficiency organic photovoltaic systems,and there is no solution to the deterioration of the stability of hybrid solar cells after the introduction of PQDs.In this work,different all-inorganic PQDs were introduced into high-efficiency organic solar cells to prepare hybrid solar cells,achieving the simultanceous enhancement of device efficiency and stability.The main contents are as follow:（1）With the introduction of CsPbBr₃ all-inorganic PQDs synthesized by thermal injection method into the active layer of PM6:Y6-BO OSCs,the light absorption was enhanced due to the Rayleigh scattering effect,resulting in increased short-circuit current of the devices.The suitable HOMO energy level of CsPbBr₃PQDs improves hole transfer between the donor and acceptor,promotes exciton dissociation in the acceptor phase,and thereby improves the short-circuit current and fill factor of devices.CsPbBr₃ PQDs with a more suitable tolerance factor have better stability in ambient,resulting in better device stability compared to the CsPbI₃PQDs based devices.The PCE of the final devices were increased from 16.4%to17.1%after the introduction of CsPbBr₃ PQDs,and the encapsulated devices still maintained 88%of the initial efficiency after 35 days of storage in ambient.（2）By tuning the halogen composition of CsPbX₃ PQDs,CsPbI₂Br PQDs were prepared and their presence can also enhance the light absorption of OSCs.Importantly,the PL emission of the as-prepared CsPbI₂Br PQDs shows a clear overlap with the absorption spectrum of PM6,resulting in efficient energy transfer from the CsPbI₂Br PQDs to the donor PM6,which promotes the production of charge carriers between donor and acceptor and leads to the improvement of short-circuit current.Finally,the efficiency of the PM6:BTP-C5-16 devices was improved from 16.5%to 17.5%with the introduction of CsPbI₂Br PQDs,and the encapsulated devices maintained 89%of their initial efficiency after 25 days of storage in ambient.