Two kinds of novel fluorescent hyperbranched polymers were synthesized by the end-capping approach. The fluorescent hyperbranched polyether (FPEOTM) was obtained by end capping the hyperbranched poly(hydroxyl ether) (...Two kinds of novel fluorescent hyperbranched polymers were synthesized by the end-capping approach. The fluorescent hyperbranched polyether (FPEOTM) was obtained by end capping the hyperbranched poly(hydroxyl ether) (PEOTM) with guest molecules N,N-dimethylaminobenzaldehyde (DMABA). In addition, in the presence of triethylamine, the hyperbranched polysulfone-amine with terminal double bonds (HPSA) was synthesized by polyaddition of a new AB2 type monomer (SAP, sulfone amine piperazine) at 40℃ for 60 h in chloroform solution. Then the fluorescent hyperbranched polysulfone-amine (FHPSA) was prepared by addition of guest molecules N,N-dimethylaminoanilines (DMAA) with the terminal double bonds of HPSA. The two resulting polymers fluoresce yellow-green color in both solid and solution states. The maximum emission wavelength is (460 ±10) nm and (470±10) nm, respectively. A novel 'complex quenching effect' for hyperbranched polymer was observed. The fluorescence can be quenched by transition metal展开更多
Most research on copolymers with fluorinated monomers has focused on the relationship between fluorinated monomer content and the corresponding surface structure. However,the influence of the non-fluorinated block on ...Most research on copolymers with fluorinated monomers has focused on the relationship between fluorinated monomer content and the corresponding surface structure. However,the influence of the non-fluorinated block on the surface structure of the copolymer film is unknown. Various molecular weight poly(butyl methacrylates) (PBMA) end-capped with 2-perfluorooctylethyl methacrylate (FMA) units (PBMA-ec-FMA) have been synthesized by atom transfer radical polymerization (ATRP). The effect of the PBMA block length on the surface structure and properties of the polymers both in the solid state and in solution was investigated using various techniques. X-ray photoelectron spectroscopy (XPS),sum frequency generation (SFG) vibrational spectroscopy and X-ray diffraction (XRD) analyses indicated that longer PBMA blocks enhanced both the enrichment of the fluorinated moieties and the order of the packing orientation of the perfluoroalkyl side chains on the surface. This enhancement was attributed mainly to the molecular aggregate structure of the end-capped polymers with long PBMA blocks in the solution and to the interfacial structure at the air/liquid interface,which favors the -(CF2)7CF3 moieties self-assembling on the polymer surface during film formation. This observation suggests that the polyacrylate block structure in fluorinated diblock copolymers,in addition to the fluorinated monomer content,plays an important role in structure formation on the solid surface.展开更多
A series of novel wide bandgap small molecules(IFT-ECA, IFT-M, IFT-TH and IFT-IC) based on the A-D-A structure with indenofluorene core, thiophene bridge, and different electron-deficient end-capping groups, were synt...A series of novel wide bandgap small molecules(IFT-ECA, IFT-M, IFT-TH and IFT-IC) based on the A-D-A structure with indenofluorene core, thiophene bridge, and different electron-deficient end-capping groups, were synthesized and used as non-fullerene acceptors in organic solar cells. The influences of end-capping groups on the device performance were studied.The four materials exhibited different physical and chemical properties due to the variation of end-capping groups, which further affect the exciton dissociation, charge transport, morphology of the bulk-heterojunction films and device performance. Among them, IFT-IC-based device delivered the best power conversion efficiency of 7.16% due to proper nano-scale phase separation morphology and high electron mobility, while the devices based on the other acceptors achieved lower device performance(4.14% for IFT-TH, <1% for IFT-ECA and IFT-M). Our results indicate the importance of choosing suitable electron-withdrawing groups to construct high-performance non-fullerene acceptors based on A-D-A motif.展开更多
The effects of end-capped modifications of a polymer donor with high molecular weight on non-fullerene solar cells are largely ignored,even if the chain-end-functionalized method of conjugated polymers is an effective...The effects of end-capped modifications of a polymer donor with high molecular weight on non-fullerene solar cells are largely ignored,even if the chain-end-functionalized method of conjugated polymers is an effective strategy in modulating polymeric optical-electronic properties.In this study,we design and synthesize an end-capped polymer,PM6TPO,via a reaction with the parent polymer PM6.Meanwhile,the conventional detection methods of X-ray photoelectron spectroscopy(XPS),matrix-assisted laser desorption/ionization time-of-flight(MALDI-TOF),and ^(1)H nuclear magnetic resonance(^(1)H NMR) were replaced by simple solution-based inductively coupled plasma-mass spectrometry(ICP-MS) to evaluate the end-capped efficacy of PM6TPO.By introducing end-capped groups on a high molecular weight polymer donor,we could finely tune the aggregated behavior,strengthen the miscibility between the donor and acceptor without sacrificing the strong aggregated properties,and reduce the non-radiative recombination with a lower energy loss.Therefore,the PM6TPO-based organic solar cell(OSC)realized a higher open-circuit voltage of 0.843 V and PCE of 17.26% than that of the non-end-capped parent polymer,PM6(0.824 V and 16.21%,respectively).This work not only provides a straightforward method for verifying the end-capped efficacy of a high molecular weight polymer but also indicates a new research direction for improving the photovoltaic performance of non-fullerene-based solar cells.展开更多
Copolymers of 9,9-dioctylfluorene (DOF) and 2-thienyl-benzothiadiazole (DBT) were synthesized by Suzuki reaction and end-capped by N-hexyl-carbazole and benzene, which were abbreviated as PDOF-DBT-Cz and PDOF-DBT-B, r...Copolymers of 9,9-dioctylfluorene (DOF) and 2-thienyl-benzothiadiazole (DBT) were synthesized by Suzuki reaction and end-capped by N-hexyl-carbazole and benzene, which were abbreviated as PDOF-DBT-Cz and PDOF-DBT-B, respectively. The photophysical, electrochemical and thermal properties of the copolymers were studied. The results indicated that replacement of N-hexyl-carbazole as end-capping group of PDOF-DBT can vary light color and improve luminescence efficiency.展开更多
Using titrimetric method,enzymatic behavior of lipase AK against fullerene end-capped polycaprolactone(C60-PCL) was studied for the first time,compared with polycaprolactone(PCL).The results showed that degradation of...Using titrimetric method,enzymatic behavior of lipase AK against fullerene end-capped polycaprolactone(C60-PCL) was studied for the first time,compared with polycaprolactone(PCL).The results showed that degradation of both C60-PCL and PCL by lipase followed Mechaelis-Menten equation,with the degradation parameters of PCL and C60-PCL were 0.75 mg mL-1 and 0.16 mg mL-1 for Km,and 0.90 mL h-1 and 0.43 mL h-1 for Vmax,respectively.C60-PCL had a slower degradation rate than PCL under the same conditions.These data indicated that the introduction of fullerene enabled PCL hard to be degraded by lipase.展开更多
文摘Two kinds of novel fluorescent hyperbranched polymers were synthesized by the end-capping approach. The fluorescent hyperbranched polyether (FPEOTM) was obtained by end capping the hyperbranched poly(hydroxyl ether) (PEOTM) with guest molecules N,N-dimethylaminobenzaldehyde (DMABA). In addition, in the presence of triethylamine, the hyperbranched polysulfone-amine with terminal double bonds (HPSA) was synthesized by polyaddition of a new AB2 type monomer (SAP, sulfone amine piperazine) at 40℃ for 60 h in chloroform solution. Then the fluorescent hyperbranched polysulfone-amine (FHPSA) was prepared by addition of guest molecules N,N-dimethylaminoanilines (DMAA) with the terminal double bonds of HPSA. The two resulting polymers fluoresce yellow-green color in both solid and solution states. The maximum emission wavelength is (460 ±10) nm and (470±10) nm, respectively. A novel 'complex quenching effect' for hyperbranched polymer was observed. The fluorescence can be quenched by transition metal
基金Supported by the National Natural Science Foundation of China (Grant Nos. 50573069 & 20704038) Program for Changjiang Scholars and Innovative Re-search Team in University (Grant No. IRT 0654)
文摘Most research on copolymers with fluorinated monomers has focused on the relationship between fluorinated monomer content and the corresponding surface structure. However,the influence of the non-fluorinated block on the surface structure of the copolymer film is unknown. Various molecular weight poly(butyl methacrylates) (PBMA) end-capped with 2-perfluorooctylethyl methacrylate (FMA) units (PBMA-ec-FMA) have been synthesized by atom transfer radical polymerization (ATRP). The effect of the PBMA block length on the surface structure and properties of the polymers both in the solid state and in solution was investigated using various techniques. X-ray photoelectron spectroscopy (XPS),sum frequency generation (SFG) vibrational spectroscopy and X-ray diffraction (XRD) analyses indicated that longer PBMA blocks enhanced both the enrichment of the fluorinated moieties and the order of the packing orientation of the perfluoroalkyl side chains on the surface. This enhancement was attributed mainly to the molecular aggregate structure of the end-capped polymers with long PBMA blocks in the solution and to the interfacial structure at the air/liquid interface,which favors the -(CF2)7CF3 moieties self-assembling on the polymer surface during film formation. This observation suggests that the polyacrylate block structure in fluorinated diblock copolymers,in addition to the fluorinated monomer content,plays an important role in structure formation on the solid surface.
基金supported by the Ministry of Science and Technology(2014CB643501)the National Natural Science Foundation of China(21520102006,21634004,21490573)the Guangdong Natural Science Foundation(S2012030006232)
文摘A series of novel wide bandgap small molecules(IFT-ECA, IFT-M, IFT-TH and IFT-IC) based on the A-D-A structure with indenofluorene core, thiophene bridge, and different electron-deficient end-capping groups, were synthesized and used as non-fullerene acceptors in organic solar cells. The influences of end-capping groups on the device performance were studied.The four materials exhibited different physical and chemical properties due to the variation of end-capping groups, which further affect the exciton dissociation, charge transport, morphology of the bulk-heterojunction films and device performance. Among them, IFT-IC-based device delivered the best power conversion efficiency of 7.16% due to proper nano-scale phase separation morphology and high electron mobility, while the devices based on the other acceptors achieved lower device performance(4.14% for IFT-TH, <1% for IFT-ECA and IFT-M). Our results indicate the importance of choosing suitable electron-withdrawing groups to construct high-performance non-fullerene acceptors based on A-D-A motif.
基金financially supported by the Beijing Natural Science Foundation (2212032)the National Natural Science Foundation of China (21774003, 51873221, 52073292, 51673207, 51373183)+1 种基金the Key Laboratory of Bioinspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, the Chinese Academy of Sciences, Beijing Municipal Science & Technology Commission (Z181100004418012)the Beihang University Youth Talent Support Program (YWF-18-BJ-J-218)。
文摘The effects of end-capped modifications of a polymer donor with high molecular weight on non-fullerene solar cells are largely ignored,even if the chain-end-functionalized method of conjugated polymers is an effective strategy in modulating polymeric optical-electronic properties.In this study,we design and synthesize an end-capped polymer,PM6TPO,via a reaction with the parent polymer PM6.Meanwhile,the conventional detection methods of X-ray photoelectron spectroscopy(XPS),matrix-assisted laser desorption/ionization time-of-flight(MALDI-TOF),and ^(1)H nuclear magnetic resonance(^(1)H NMR) were replaced by simple solution-based inductively coupled plasma-mass spectrometry(ICP-MS) to evaluate the end-capped efficacy of PM6TPO.By introducing end-capped groups on a high molecular weight polymer donor,we could finely tune the aggregated behavior,strengthen the miscibility between the donor and acceptor without sacrificing the strong aggregated properties,and reduce the non-radiative recombination with a lower energy loss.Therefore,the PM6TPO-based organic solar cell(OSC)realized a higher open-circuit voltage of 0.843 V and PCE of 17.26% than that of the non-end-capped parent polymer,PM6(0.824 V and 16.21%,respectively).This work not only provides a straightforward method for verifying the end-capped efficacy of a high molecular weight polymer but also indicates a new research direction for improving the photovoltaic performance of non-fullerene-based solar cells.
基金Supported by the Major Project of Science Foundation Ministry of Education of China (Grant No. 207015)the National Natural Science Foundation of China (Grant No. 20671068)
文摘Copolymers of 9,9-dioctylfluorene (DOF) and 2-thienyl-benzothiadiazole (DBT) were synthesized by Suzuki reaction and end-capped by N-hexyl-carbazole and benzene, which were abbreviated as PDOF-DBT-Cz and PDOF-DBT-B, respectively. The photophysical, electrochemical and thermal properties of the copolymers were studied. The results indicated that replacement of N-hexyl-carbazole as end-capping group of PDOF-DBT can vary light color and improve luminescence efficiency.
基金supported by the National Natural Science Foundation of China (20672012)Beijing Municipal Natural Science Foundation (20822020)
文摘Using titrimetric method,enzymatic behavior of lipase AK against fullerene end-capped polycaprolactone(C60-PCL) was studied for the first time,compared with polycaprolactone(PCL).The results showed that degradation of both C60-PCL and PCL by lipase followed Mechaelis-Menten equation,with the degradation parameters of PCL and C60-PCL were 0.75 mg mL-1 and 0.16 mg mL-1 for Km,and 0.90 mL h-1 and 0.43 mL h-1 for Vmax,respectively.C60-PCL had a slower degradation rate than PCL under the same conditions.These data indicated that the introduction of fullerene enabled PCL hard to be degraded by lipase.
