To construct efficient low band gap polymers,increasing the Quinone structure of the polymer backbone could be one desirable strategy.In this work,two D–Q–A–Q polymers P1 and P2 were designed and synthesized with t...To construct efficient low band gap polymers,increasing the Quinone structure of the polymer backbone could be one desirable strategy.In this work,two D–Q–A–Q polymers P1 and P2 were designed and synthesized with thiophenopyrrole diketone(TPD)and benzothiadiazole(BT)unit as the core and ester linked thieno[3,4-b]thiophene(TT)segment as π-bridging,and the main focus is to make a comparative analysis of different cores in the influence of the optical,electrochemical,photochemical and morphological properties.Compared with the reported PBDTTEH–TBTTHD-i,P1 exhibited the decreased HOMO energy level of-5.38 e V and lower bandgap of 1.48 e V.Furthermore,when replaced with BT core,P2 showed a red-shifted absorption profile of polymer but with up-shifted HOMO energy level.When fabricated the photovoltaic devices in conventional structure,just as expected,the introduction of ester substituent made an obvious increase of VOC from 0.63 to 0.74 V for P1.Besides,due to the deep HOMO energy level,higher hole mobility and excellent phase separation with PC71 BM,a superior photovoltaic performance(PCE=7.13%)was obtained with a short-circuit current density(JSC)of 14.9 m A/cm^2,significantly higher than that of P2(PCE=2.23%).Generally,this study highlights that the strategy of inserting quinoid moieties into D–A polymers could be optional in LBG-polymers design and presents the importance and comparison of potentially competent core groups.展开更多
The concept of introducing n-conjugated but anti-aromatic repeating units into conjugated polymers has been explored. The thermal stability, optical and electrochemical properties of dithieno[a,e]pentalenes (DTP) ba...The concept of introducing n-conjugated but anti-aromatic repeating units into conjugated polymers has been explored. The thermal stability, optical and electrochemical properties of dithieno[a,e]pentalenes (DTP) based polymers have been studied. The effect of introducing electron withdrawing repeating units into DTP based poly- mer on the physical properties of polymer has also been investigated. The new polymers showed broad absorption in visible and near-infrared region.展开更多
1 Results Low bandgap polymers can be used for pure red light emitting materials or solar cell materials.To make low bandgap polymers,we designed conjugated polymers with alternating sequences of the appropriate donor...1 Results Low bandgap polymers can be used for pure red light emitting materials or solar cell materials.To make low bandgap polymers,we designed conjugated polymers with alternating sequences of the appropriate donor/acceptor units in the main chain.3-hexyl thiophene was used as a electron donating unit.For the electron accepting unit,we selected thiazolothiazole and bithiazole units having electron withdrawing property.Polyfluorene(PF) is the preferred conjugated polymer in light-emitting applications...展开更多
基金the National Natural Science Foundation of China (21604092, 51573205 and 51773220)China Postdoctoral Science Foundation (2017M610453+1 种基金the Youth Innovation Promotion Association CAS (2016194) for financial supportthe CAS-TWAS President’s Fellowship Program for Ph.D
文摘To construct efficient low band gap polymers,increasing the Quinone structure of the polymer backbone could be one desirable strategy.In this work,two D–Q–A–Q polymers P1 and P2 were designed and synthesized with thiophenopyrrole diketone(TPD)and benzothiadiazole(BT)unit as the core and ester linked thieno[3,4-b]thiophene(TT)segment as π-bridging,and the main focus is to make a comparative analysis of different cores in the influence of the optical,electrochemical,photochemical and morphological properties.Compared with the reported PBDTTEH–TBTTHD-i,P1 exhibited the decreased HOMO energy level of-5.38 e V and lower bandgap of 1.48 e V.Furthermore,when replaced with BT core,P2 showed a red-shifted absorption profile of polymer but with up-shifted HOMO energy level.When fabricated the photovoltaic devices in conventional structure,just as expected,the introduction of ester substituent made an obvious increase of VOC from 0.63 to 0.74 V for P1.Besides,due to the deep HOMO energy level,higher hole mobility and excellent phase separation with PC71 BM,a superior photovoltaic performance(PCE=7.13%)was obtained with a short-circuit current density(JSC)of 14.9 m A/cm^2,significantly higher than that of P2(PCE=2.23%).Generally,this study highlights that the strategy of inserting quinoid moieties into D–A polymers could be optional in LBG-polymers design and presents the importance and comparison of potentially competent core groups.
基金National Natural Science Foundation of China,by Doctoral Fund of Ministry of Education of China
文摘The concept of introducing n-conjugated but anti-aromatic repeating units into conjugated polymers has been explored. The thermal stability, optical and electrochemical properties of dithieno[a,e]pentalenes (DTP) based polymers have been studied. The effect of introducing electron withdrawing repeating units into DTP based poly- mer on the physical properties of polymer has also been investigated. The new polymers showed broad absorption in visible and near-infrared region.
文摘1 Results Low bandgap polymers can be used for pure red light emitting materials or solar cell materials.To make low bandgap polymers,we designed conjugated polymers with alternating sequences of the appropriate donor/acceptor units in the main chain.3-hexyl thiophene was used as a electron donating unit.For the electron accepting unit,we selected thiazolothiazole and bithiazole units having electron withdrawing property.Polyfluorene(PF) is the preferred conjugated polymer in light-emitting applications...