All polymer solar cells （all-PSCs）, possessing superior mechanical strength and flexibility, offer the commercialization opportunity of the PSCs for flexible and portable devices. In this work, we designed and synth...All polymer solar cells （all-PSCs）, possessing superior mechanical strength and flexibility, offer the commercialization opportunity of the PSCs for flexible and portable devices. In this work, we designed and synthesized two copolymer acceptors based on dicyanodistyrylbenzene （DCB） and naph-thalene diimide （NDI） units. The corresponding copolymer acceptors are denoted as PDCB-NDI812 and PDCB-NDI1014. The medium band gap copolymer PBDB-T was selected as donor material for investigation of the photovoltaic performance. Two alI-PSCs devices showed power conversion efficiencies （PCE） of 4.26% and 3.43% for PDCB-NDI812 and PDCB-NDI1014, respectively. The improved PCE was ascribed to the higher short-circuit current （Jsc）, greater charge carrier mobility and higher exciton dissociation probability of the PBDB-T：PDCB-NDI812 blend film. These results suggest that DCB unit and NDI unit based copolymer acceptors are promising candidates for high performance alI-PSCs.展开更多
Why many luminescent liquid crystalline polymers(LLCPs)containing aggregation-induced emission luminogen(AIEgen)show weak emission is a question still to be answered.Herein,a series of LLCPs(α-Pns,n=4,8,and 12)with p...Why many luminescent liquid crystalline polymers(LLCPs)containing aggregation-induced emission luminogen(AIEgen)show weak emission is a question still to be answered.Herein,a series of LLCPs(α-Pns,n=4,8,and 12)with polynorbornene as main chain and twoα-dicyanodistyrylbenzene(α-DCS)as side chain are successfully synthesized to solve this issue.Differential scanning calorimetry(DSC),polarized light microscopy(PLM),one-dimentional(1D),two-dimentional(2D)middle-angle and wide-angle X-ray scattering(MAXS and WAXS)results demonstrate that the polymers form smectic A(SmA)phase with the side chains interdigitated packed within the smectic layers.Meanwhile,the photophysical properties ofα-Pns were investigated by ultraviolet-visible(UV-vis)absorption,steady state and time-resolved spectroscopy,and photothermal effect.Results show that the polymers are AIE active,but emit weak emission.The emission peak ofα-Pns film red-shift from 473 to 531 nm,the quantum yield gradually increases from around 1.6%to 14.7%,and the photothermal conversion efficiency decreases from 39%to 19%with the alkyl tail length increased.The photothermal effect,but not photoluminescence,dominates the excited state relaxation.展开更多
文摘All polymer solar cells （all-PSCs）, possessing superior mechanical strength and flexibility, offer the commercialization opportunity of the PSCs for flexible and portable devices. In this work, we designed and synthesized two copolymer acceptors based on dicyanodistyrylbenzene （DCB） and naph-thalene diimide （NDI） units. The corresponding copolymer acceptors are denoted as PDCB-NDI812 and PDCB-NDI1014. The medium band gap copolymer PBDB-T was selected as donor material for investigation of the photovoltaic performance. Two alI-PSCs devices showed power conversion efficiencies （PCE） of 4.26% and 3.43% for PDCB-NDI812 and PDCB-NDI1014, respectively. The improved PCE was ascribed to the higher short-circuit current （Jsc）, greater charge carrier mobility and higher exciton dissociation probability of the PBDB-T：PDCB-NDI812 blend film. These results suggest that DCB unit and NDI unit based copolymer acceptors are promising candidates for high performance alI-PSCs.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.21875143,21674065,and 21975215)the Innovation Research Foundation of Shenzhen(Nos.SGG20190222175202275,JCYJ20180507182229597,and JCYJ20180305125649693)the Natural Science Foundation of Guangdong Province(No.2016A030312002)。
文摘Why many luminescent liquid crystalline polymers(LLCPs)containing aggregation-induced emission luminogen(AIEgen)show weak emission is a question still to be answered.Herein,a series of LLCPs(α-Pns,n=4,8,and 12)with polynorbornene as main chain and twoα-dicyanodistyrylbenzene(α-DCS)as side chain are successfully synthesized to solve this issue.Differential scanning calorimetry(DSC),polarized light microscopy(PLM),one-dimentional(1D),two-dimentional(2D)middle-angle and wide-angle X-ray scattering(MAXS and WAXS)results demonstrate that the polymers form smectic A(SmA)phase with the side chains interdigitated packed within the smectic layers.Meanwhile,the photophysical properties ofα-Pns were investigated by ultraviolet-visible(UV-vis)absorption,steady state and time-resolved spectroscopy,and photothermal effect.Results show that the polymers are AIE active,but emit weak emission.The emission peak ofα-Pns film red-shift from 473 to 531 nm,the quantum yield gradually increases from around 1.6%to 14.7%,and the photothermal conversion efficiency decreases from 39%to 19%with the alkyl tail length increased.The photothermal effect,but not photoluminescence,dominates the excited state relaxation.
