The molecular orientations of conjugated materials on the substrate mainly include edge-on,face-on,and end-on.Edge-on and face-on orientations have been widely observed,while end-on orientation has been rarely reporte...The molecular orientations of conjugated materials on the substrate mainly include edge-on,face-on,and end-on.Edge-on and face-on orientations have been widely observed,while end-on orientation has been rarely reported.Since in organic solar cells(OSCs)charge transport is along the vertical direction,end-on orientation with conjugated backbones perpendicular to the substrate is recognized as the ideal microstructure for OSCs.In this work,we for the first time obtained the preferential end-on orientation in a conjugated molecular dyad that contains a conjugated backbone as donor and perylene bisimide side units as acceptor.This was realized by introducing a fused-ring structure to replace linear terthiophenes with conjugated backbones,yielding F-MDPBI and L-MDPBI respectively.Surprisingly,a shifting trend of the molecular orientation from dominating edge-on in L-MDPBI to preferential end-on in F-MDPBI was observed.As a consequence,vertical charge carrier mobilities in F-MDPBI are one order of magnitude higher than those with preferential edge-on orientation,so single-component OSCs based on this molecular dyad as a single photoactive layer provided a power conversion efficiency of 4.89% compared to 1.70% based on L-MDPBI with preferential edge-on orientation.展开更多
In this work,semirigid linkers of the alkyl-thiophene-alkyl structure are developed to construct double-cable polymers.Three alkyl units,propyl(C3H6),hexyl(C6H12),and dodecyl(C12H24),are applied as semirigid linkers,y...In this work,semirigid linkers of the alkyl-thiophene-alkyl structure are developed to construct double-cable polymers.Three alkyl units,propyl(C3H6),hexyl(C6H12),and dodecyl(C12H24),are applied as semirigid linkers,yielding three double-cable polymers:PBC6-T,PBC12-T,and PBC24-T,respectively.PBC12-T which uses C6H12-thiophene-C6H12 linkers is found to exhibit the best device efficiency of 5.56%,while PBC6-T and PBC24-T with shorter or longer linkers yield device efficiencies of only 2.65%and 1.09%in single-component organic solar cells(SCOSCs).Further studies reveal that PBC12-T exhibits higher crystallinity and improved charge transport,resulting in better efficiencies.Our work provides an approach to construct double-cable conjugated polymers with long alkyl linkers,and it shows the importance of the linker length for the photovoltaic performance of SCOSCs.展开更多
The photovoltaic properties of double-cable conjugated polymers are significantly influenced by the length of the alkyl linkers that connect donor backbones and acceptor side units. In this study, a series of 2-(3-oxo...The photovoltaic properties of double-cable conjugated polymers are significantly influenced by the length of the alkyl linkers that connect donor backbones and acceptor side units. In this study, a series of 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile(IC)-based double-cable polymers with alkyl linkers ranging from C_8H_(16)to C_(16)H_(32)(Px, x = 8, 10, 12, 14, 16) were synthesized for single-component organic solar cells(SCOSCs). Among these, the linker length x = 12(P12) is found to optimize the power conversion efficiencies(PCEs) in SCOSCs. Specifically, PCEs increase from P8 to P12 and then decline from P12to P16. Detailed investigations of optical absorption, charge transport, and morphology provide insights into the underlying factors contributing to these PCE variations. The findings indicate that the exceptional photovoltaic properties observed in P12 can be attributed to three key factors: A delicate balance between enhanced charge separation facilitated by the increased spacer length and reduced crystallinity resulting from longer spacers, higher charge mobilities, and well-balanced hole/electron transport characteristics. This study highlights the critical role of linker length in determining the photovoltaic properties of double-cable conjugated polymer-based SCOSCs and offers valuable guidance for the design of novel double-cable conjugated polymers.展开更多
A series of single-composition emission-tunable CdWO4:Eu^3+ uniform size nanorods were synthesized by polyvinylpyrrolidone(PVP) assisted hydrothermal process. The products were measured by powder X-ray diffraction...A series of single-composition emission-tunable CdWO4:Eu^3+ uniform size nanorods were synthesized by polyvinylpyrrolidone(PVP) assisted hydrothermal process. The products were measured by powder X-ray diffraction(PXRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), photoluminescence, and fluorescent decay test. The results showed that reaction time, temperature, p H values and Eu^3+ doped concentration played important roles in determining the morphologies and photoluminescent properties. And we also investigated its use in Ga N LED, warm-white-light could be obtained by the combination of the bright blue light originated from the charge transfer transition in the tungstate groups and the near UV light from LED chip with the red emission from 4f-4f transition of Eu^3+, respectively. By properly tuning the doping concentration of Eu^3+, chromaticity coordinates(0.30 0.22) could be achieved under the 380 nm excitation and its color rendering index was 80.6. So it has potential application in warm-WLED and replacing the commercial YAG:Ce phosphor which absence of red band emission.展开更多
Herein,a novel dual-emission fluorescence sensor array of carbonized polymer dots(CPDs)-Cu^(2+)has been proposed,in which CPDs were prepared by one-pot hydrothermal method and Cu^(2+)acting as a quencher was combined ...Herein,a novel dual-emission fluorescence sensor array of carbonized polymer dots(CPDs)-Cu^(2+)has been proposed,in which CPDs were prepared by one-pot hydrothermal method and Cu^(2+)acting as a quencher was combined with CPDs by electrostatic interaction.Four negatively charged glycosaminoglycans(GAGs)bearing different hydrophilic groups showed variable binding affinities towards CPDs-Cu^(2+).Upon reacting with these GAGs,the different fluorescence response signals of CPDs-Cu^(2+)can be further differentiated by principal component analysis(PCA).The CPDs-Cu^(2+)sensor array,not only allows the identification of four similarly structured GAGs,but also realizes the discrimination of different concentrations of the same GAGs and their mixtures.Remarkably,the identification of GAGs in biological fluids can also be achieved using our proposed single-component sensor array,validating its application potential.This new strategy avoids multiple sensing probes,broadens the application of tongue-mimic sensor arrays and provides a viable idea for the development of single component sensing platforms.展开更多
The recently emerged double-cable conjugated polymers have come into focus due to their significantly improved power conversion efficiencies (PCEs) in single-component organic solar cells (SCOSCs). In this work, the e...The recently emerged double-cable conjugated polymers have come into focus due to their significantly improved power conversion efficiencies (PCEs) in single-component organic solar cells (SCOSCs). In this work, the effect of chlorination in double-cable conjugated polymers with linear benzodithiophene backbone and pendant perylene bisimide on the photovoltaic performance in SCOSCs has been studied. After introducing chlorine atoms into conjugated side chains, the highest occupied molecular orbital level of the conjugated polymers is down-shifted, thus resulting in a higher open-circuit voltage. As a result, the chlorinated double-cable conjugated polymer exhibits improved photovoltaic performance from 3.46% to 3.57%.展开更多
基金Beijing Natural Science Foundation,Grant/Award Number:JQ210065NSFC,Grant/Award Numbers:52073016,92163128+4 种基金Fundamental Research Funds for the Central Universities,Grant/Award Numbers:buctrc201828,XK1802-2The opening Foundation of State Key Laboratory of Organic-Inorganic Composites,Beijing University of Chemical Technology,Grant/Award Number:oic-202201006Jiangxi Provincial Department of Science and Technology,Grant/Award Numbers:20202ACBL213004,20212BCJ23035,jxsq2019102004,20203BBE53062Jiangxi Academy of Sciences,Grant/Award Numbers:2021YSBG22034,2021YSBG22033,2020-YZD-3Australian Research Council,Grant/Award Number:FT180100594。
文摘The molecular orientations of conjugated materials on the substrate mainly include edge-on,face-on,and end-on.Edge-on and face-on orientations have been widely observed,while end-on orientation has been rarely reported.Since in organic solar cells(OSCs)charge transport is along the vertical direction,end-on orientation with conjugated backbones perpendicular to the substrate is recognized as the ideal microstructure for OSCs.In this work,we for the first time obtained the preferential end-on orientation in a conjugated molecular dyad that contains a conjugated backbone as donor and perylene bisimide side units as acceptor.This was realized by introducing a fused-ring structure to replace linear terthiophenes with conjugated backbones,yielding F-MDPBI and L-MDPBI respectively.Surprisingly,a shifting trend of the molecular orientation from dominating edge-on in L-MDPBI to preferential end-on in F-MDPBI was observed.As a consequence,vertical charge carrier mobilities in F-MDPBI are one order of magnitude higher than those with preferential edge-on orientation,so single-component OSCs based on this molecular dyad as a single photoactive layer provided a power conversion efficiency of 4.89% compared to 1.70% based on L-MDPBI with preferential edge-on orientation.
基金the Beijing Natural Science Foundation(No.JQ21006)the Ministry of Science and Technology(No.2018YFA0208504)+3 种基金the National Natural Science Foundation(Nos.92163128,52073016,21905018)of Chinathe Fundamental Research Funds for the Central Universities(Nos.buctrc201828,XK1802-2)Open Project of State Key Laboratory of Organic-Inorganic Composites(No.oic-202201006)Open Project of State Key Laboratory of Supramolecular Structure and Materials(No.sklssm202209).
文摘In this work,semirigid linkers of the alkyl-thiophene-alkyl structure are developed to construct double-cable polymers.Three alkyl units,propyl(C3H6),hexyl(C6H12),and dodecyl(C12H24),are applied as semirigid linkers,yielding three double-cable polymers:PBC6-T,PBC12-T,and PBC24-T,respectively.PBC12-T which uses C6H12-thiophene-C6H12 linkers is found to exhibit the best device efficiency of 5.56%,while PBC6-T and PBC24-T with shorter or longer linkers yield device efficiencies of only 2.65%and 1.09%in single-component organic solar cells(SCOSCs).Further studies reveal that PBC12-T exhibits higher crystallinity and improved charge transport,resulting in better efficiencies.Our work provides an approach to construct double-cable conjugated polymers with long alkyl linkers,and it shows the importance of the linker length for the photovoltaic performance of SCOSCs.
基金jointly supported by the Beijing Natural Science Foundation (Nos.2212045 and JQ21006)the National Natural Science Foundation of China (Nos.21905158, 52073016 and 92163128)+2 种基金further supported by the Fundamental Research Funds for the Central Universities (Nos.buctrc202111, buctrc201828, and XK1802-2)the Opening Foundation of State Key Laboratory of Organic-Inorganic Composites of Beijing University of Chemical Technology (No.oic-202201006)Jiangxi Provincial Department of Science and Technology (Nos.20202ACBL213004, 20212BCJ23035, jxsq2019102004)。
文摘The photovoltaic properties of double-cable conjugated polymers are significantly influenced by the length of the alkyl linkers that connect donor backbones and acceptor side units. In this study, a series of 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile(IC)-based double-cable polymers with alkyl linkers ranging from C_8H_(16)to C_(16)H_(32)(Px, x = 8, 10, 12, 14, 16) were synthesized for single-component organic solar cells(SCOSCs). Among these, the linker length x = 12(P12) is found to optimize the power conversion efficiencies(PCEs) in SCOSCs. Specifically, PCEs increase from P8 to P12 and then decline from P12to P16. Detailed investigations of optical absorption, charge transport, and morphology provide insights into the underlying factors contributing to these PCE variations. The findings indicate that the exceptional photovoltaic properties observed in P12 can be attributed to three key factors: A delicate balance between enhanced charge separation facilitated by the increased spacer length and reduced crystallinity resulting from longer spacers, higher charge mobilities, and well-balanced hole/electron transport characteristics. This study highlights the critical role of linker length in determining the photovoltaic properties of double-cable conjugated polymer-based SCOSCs and offers valuable guidance for the design of novel double-cable conjugated polymers.
基金Project supported by the National Natural Science Foundation of China(21301115)the Shanghai University Innovation Fund(sdcx2012005)Funding Scheme for Training Young Teachers in Colleges and Universities(ZZSD12025)
文摘A series of single-composition emission-tunable CdWO4:Eu^3+ uniform size nanorods were synthesized by polyvinylpyrrolidone(PVP) assisted hydrothermal process. The products were measured by powder X-ray diffraction(PXRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), photoluminescence, and fluorescent decay test. The results showed that reaction time, temperature, p H values and Eu^3+ doped concentration played important roles in determining the morphologies and photoluminescent properties. And we also investigated its use in Ga N LED, warm-white-light could be obtained by the combination of the bright blue light originated from the charge transfer transition in the tungstate groups and the near UV light from LED chip with the red emission from 4f-4f transition of Eu^3+, respectively. By properly tuning the doping concentration of Eu^3+, chromaticity coordinates(0.30 0.22) could be achieved under the 380 nm excitation and its color rendering index was 80.6. So it has potential application in warm-WLED and replacing the commercial YAG:Ce phosphor which absence of red band emission.
基金supported by the National Natural Science Foundation of China(22274053)the Fundamental Research Funds for the Central Universities
文摘Herein,a novel dual-emission fluorescence sensor array of carbonized polymer dots(CPDs)-Cu^(2+)has been proposed,in which CPDs were prepared by one-pot hydrothermal method and Cu^(2+)acting as a quencher was combined with CPDs by electrostatic interaction.Four negatively charged glycosaminoglycans(GAGs)bearing different hydrophilic groups showed variable binding affinities towards CPDs-Cu^(2+).Upon reacting with these GAGs,the different fluorescence response signals of CPDs-Cu^(2+)can be further differentiated by principal component analysis(PCA).The CPDs-Cu^(2+)sensor array,not only allows the identification of four similarly structured GAGs,but also realizes the discrimination of different concentrations of the same GAGs and their mixtures.Remarkably,the identification of GAGs in biological fluids can also be achieved using our proposed single-component sensor array,validating its application potential.This new strategy avoids multiple sensing probes,broadens the application of tongue-mimic sensor arrays and provides a viable idea for the development of single component sensing platforms.
基金the National Natural Science Foundation of China(Nos.51973169,51703172 and 52073016)the Open Project Program of Wuhan National Laboratory for Optoelectronics(No.2020WNLOKF015)the science foundation of Wuhan Institute of Technology(No.K202025).
文摘The recently emerged double-cable conjugated polymers have come into focus due to their significantly improved power conversion efficiencies (PCEs) in single-component organic solar cells (SCOSCs). In this work, the effect of chlorination in double-cable conjugated polymers with linear benzodithiophene backbone and pendant perylene bisimide on the photovoltaic performance in SCOSCs has been studied. After introducing chlorine atoms into conjugated side chains, the highest occupied molecular orbital level of the conjugated polymers is down-shifted, thus resulting in a higher open-circuit voltage. As a result, the chlorinated double-cable conjugated polymer exhibits improved photovoltaic performance from 3.46% to 3.57%.