Synthesis And Photovoltaic Applications Of Perylene Monoimide Acceptors And Random Copolymers

Perylene monoimide?PMI?has the advantages of high extinction coefficient,suitable energy level,and high thermal stability,but it is rarely used in organic solar cells because of its difficult modification and poor solubility.Photovoltaic application of PMI lags far behind its counterpart perylene diimides?PDI?.A series of PMI acceptors were designed and synthesized in this work,and their properties and photovoltaic applications were studied.Starting from commercial available 2,6-diisopropylaniline and perylenetetra carboxylic anhydride,key intermediate boronated PMI?Compound 4?was synt-hesized by condensation,bromination,and borylation in the overall yield of65.5%,Target compounds were obtained by Suzuki coupling reaction in the yield of 55.6%..These acceptors have strong and broad absorption between 300-650 nm,LUMO energy levels between-3.81^-3.08 eV,good solubility.Photovoltaic devices with above acceptors have high open circuit voltages as high as1.35 V.Perylene monoimide derivatives with substituents at bay position was desined and synthesized.Key intermediate borominated PMI?3Br-PMI,compound 15?was synthesized in the yield of 45.4%.Three key intermediates were synthesized by introduing chlorine,cyano,tert-butylphenoxy to the bay positions.Target compounds were obtained by Suzuki coupling reaction in the yield of 60.6%.Photovoltaic applications of these acceptors were studied.These acceptors have strong and broad absorption between 400-650 nm,and LUMO energy level between-3.60-3.65 eV The power conversion efficiencies of solar cells based on compounds19 and 20 were up to 3.92%and 4.69%,respectively.In this study,a series of PBDB-TBTn random conjugated polymer as donors is designed and synthesized,containing an dibenzodithiophene unit with thiophene conjugated side chains?BDT?donor unit and different content of benzo[1,2-c:4,5-c?]dithiophene-4,8-dione?BDD?and difluorobenzothiadizole?BT?linked alkylthiophene as acceptor unit,A series of PBDB-TBTn was synthesized by polymerization.and polymer solar cells?PSCs?are fabricated with ITIC as an acceptor over the power conversion efficiency of 9%,including open circuit voltage of 0.86 V,short-circuit current density of 16.84 mA cm^-2,and fill factor of 62.5%.