Synthesis And Photovoltaic Properties Of Ternary Polymer Donor Materials And Trapezoidal Anthracenes Small Molecule Acceptors

In recent years,energy demand is increasing and the fossil energy that people rely on is becoming less and less.To this end,the people seek clean energy and continuously develops new energy sources,of which solar energy is one of them.Solar energy is renewable and non-pollution new energy source,mainly used in two modes of photothermal and photoelectric conversion,and the utilization of solar energy can be carried out in various ways,among which solar cell equipment is converted in terms of light energy utilization.There is considerable prospect for generating electricity.In this dissertation,a series of ternary copolymers of D-A1-D-A2 structure were designed and synthesized by FTT and two electron-deficient units FBT and DPP.After that,the fused anthracene ring was used as the D unit and different end groups IC,IC-4F,TBA were used as A unit.Then three non-fullerene small molecule acceptor materials（AFIC,AFIC-4F和AFTBA）were designed and synthesized.The structure and properties of these materials were characterized,and some progress were acquired.The main contents are as follows:1.The four copolymers of FD10,FD21,FD11 and FD12 were synthesized by adjusting the ratio between FTT,FBT and DPP units,which possess a broad absorption and suitable energy levels.In the devices with these copolymer as electron donor materials and PC71BM as the electron acceptor material,the highest short-circuit current density(J_sc=12.52 mA/cm²)and 6.41%power conversion efficiency were obtained from the terpolymer FD21,in which FBT/DPP=2:1.The polymer FD10 showed the highest open circuit voltage（Voc=0.86 V）.Subsequently,we made ternary device for improving the photovoltaic performance of the battery further.The polymers of FD10 and FD21 were blended as donor materials of solar cells by different mass ratios,and a maximal PCE of 7.04%was obtained.2.The A-D-A structural molecules were designed based on the trapezoidal conjugated fused ring（AF）and the different terminal groups（IC,IC-4F and TBA）.And three small molecule non-fullerene acceptor materials of AFIC,AFIC-4F and AFTBA were successfully synthesized.Relative to the introduction of TBA groups,the IC and IC-4F groups make the material band gap narrower and the absorption red shifts up to 1000 nm.The bulk heterojunction（BHJ）solar cells with the reverse device structure were prepared by PTB7-Th as the donor materials,the device efficiencies based on the three small-molecule electron acceptor materials AFIC,AFIC-4F and AFTBA reached 3.01%,2.67%,and 2.42%,respectively.