| To accelerate commercialization of PSCs,the exploration of high-performance and low-cost polymer donors is essential.In this paper,we designed and synthesized a series of polymer donors based on acceptor units with a simple structure and low synthetic cost,and investigated their photovoltaic properties.The main contents of this dissertation are as follows:In chapter 1,we briefly introduced the knowledge of polymer solar cells,including working principle,device structure and performance parameters,then summarized several typical wide bandgap polymers.Finally,we proposed the main ideas of the paper,aiming to develop low-cost wide bandgap polymers.In chapter 2,we synthesized two wide bandgap polymers(PBBA and PBBA-Cl)based on benzobis(thiazole)(BBA)as electron-deficient unit.Compared with BDD,FBTA,and Tz BI unit,the synthesis of a BBA-based monomer is much simpler via only three step reactions.When blended with Y6,the PBBA-based devices yielded a PCE of up to 9.83%,outperforming that of PBBA-Cl-based devices(6.84%).In chapter 3,we synthesized two wide bandgap polymers(PTCO8 and PTCO1)composed of alkylcarbonyl-substituted thiophene(TOC)as electron-deficient unit and thienyl-substituted benzodithiophene(BDT)as electron-donating unit.The synthesis of alkylcarbonyl-substituted thiophene is more easy via only one or two step reactions.Relative to the polymer PTC8,both PTCO8 and PTCO1 exhibited extended absorption spectra and low-lying highest occupied molecular oribital(HOMO)energy levels.The PTCO1-based device yielded a champion PCE of 9.33%,higher than those of the PTC8devices(4.04%)and PTCO8 devices(5.91%).In chapter 4,we synthesized three polymers donors(PTEI-H,PTEI-F,and PTEICl)based on(Z)-3-(thiophen-2-yl-methylene)-indolin-2-one(TEI)as electronwithdrawing unit.The TEI unit possesses a simple molecular structure,which can be easily prepared from a two-step reaction.The TEI unit has the potential to construct low-cost polymers.After blending with Y6,the PTEI-H devices exhibited the best PCE of 8.27%. |
