Organic Acceptor Materials Based On Alkyl Ester Substituted Perylene

As a new type of solar cell,organic solar cell has the characteristics of flexibility,light weight,solution processing,large area printing and preparation,which is a hot spot in the field of solar cell research.In recent years,perylene based organic solar cells have achieved more tha-n 10%efficiency.Perylene derivatives,as an excellent n-type acceptor material,have many advantages,such as strong light absorption,high el-ectron mobility,excellent thermal stability and rich modification sites.I-n this paper,based on ester alkyl perylene,dimer was synthesized by c ondensation in bay area,and the synthetic route was optimized.The ma-in research contents are as follows:Two dimer molecules(DTBP-BDT and DTBP-DT)based on two di-fferent condensing units(BDT unit and triathiophene unit)were designe-d and sy-nthesized.As the third component,they were blended with do-nor material PM6 and acceptor material Y6 to form ternary blend solar cell.The OPV devices based on DTBP-BDT and DTBP-DT have open circuit voltage Voc of 0.87v and 0.86v,short circuit current density JSC of 24.66mA cm-2 and 25.19mA cm-2,respectively.The OPV efficiency of 16.02%and 15.74%is achieved.The results show that the conjugate-d planes of DTBP-BDT and DTBP-DT can be increased,the absorption range can be widened and the utilization efficiency of solar light can be increased by the way of synthesizing dimer.The high LUMO energy level of the obtained materials improves the open circuit voltage of ter-nary blend cells,which provides an effective strategy for improving the open circuit voltage of devices by molecular design of perylene derivat-ives.In order to solve the problem of low yield and difficult separation of perylene compounds in synthesis,a variety of design and optimization were carried out on the synthesis path:First,OTf was used to replace bromine for coupling;Second,the active sites of perylene units were reduced through bay Area cyclization,and the bromination yield was im-proved.Based on the second method,DHBP-TT was prepared by blend-ing with donor material PM6 and acceptor material Y6.The device has an open circuit voltage of 0.86V,a current density of 24.45mA cm-2 and a photovoltaic efficiency of 15.32%.