This study optimized the TADF feature of axial chiral enantiomers through precise donor engineering,and multicolor CP-TADFwas achieved in the axial chiral framework.Three pairs of axial enantiomers with donor-regulate...This study optimized the TADF feature of axial chiral enantiomers through precise donor engineering,and multicolor CP-TADFwas achieved in the axial chiral framework.Three pairs of axial enantiomers with donor-regulated TADF feature,namely(R/S)-TPCBD,(R/S)-DPCBD,and(R/S)-DPACBD,were synthesized by introducing carbazole donors with different substituents onto biphenyl cyanide acceptors.As the electron-donating ability of donors increases,the emission of these axial enantiomers ranges from 455,476 to 552 nm,their singlet-triplet energy gaps(ΔE_(ST))gradually decrease from 0.30,0.22 to 0.02 e V,accompanied by an increasement in the transition rate(k_(RISC))of RISC process,and the k_(RISC)of DPACBD could reach up to 7.16×10^(5)s^(-1).These axial enantiomers also exhibit mirror-image CD and circularly polarized luminescence(CPL)properties.Moreover,OLEDs based on TPCBD,DPCBD,and DPACBD as emitter were then fabricated,which displayed blue,green,and orange electroluminescence with EQE_(max)of 13.0%,16.4%,and 25.0%,respectively.The results also exhibited a phenomenon of device efficiency increasing with the enhancement of donor abilities.Notably,the CP-OLEDs using(R/S)-TPCBD,(R/S)-DPCBD and(R/S)-DPACBD as emitters displayed intense CPEL signals with g_(EL)values of 3.4×10^(-3)/-4.1×10^(-3),3.2×10^(-3)/-3.1×10^(-3)and2.3×10^(-3)/-2.1×10^(-3),respectively.By convenient molecular engineering of donor regulation in the same molecular skeleton,CP-TADF materials with multicolor CPEL and improved device performance could be conveniently achieved.展开更多
It is of great significance to develop effective antibacterial agents and methods to combat drug resistant bacterial infections due to its increasing threaten to human health and the ineffectiveness of antibiotics.Her...It is of great significance to develop effective antibacterial agents and methods to combat drug resistant bacterial infections due to its increasing threaten to human health and the ineffectiveness of antibiotics.Herein,a multifunctional hybrid nano-assembly(M1-Fe NPs)based on conjugated oligomer and ferrous ion was engineered with favorable bactericidal activity for synergetic antibacterial therapy.The chelation of ferrous ion not only enhances the photothermal conversion efficiency of M1 but also endows the nano-assembly with catalytic capability of transferring H_(2)O_(2) into stronger oxidant hydroxyl radicals(·OH).Meanwhile,the generated heat can further promote the Fenton reaction activity.By generating cytotoxic heat and oxidative·OH,M1-Fe NPs can effectively kill Staphylococcus aureus in vitro and in vivo with the aid of low dosage of H_(2)O_(2).The work provides a new multifunctional platform for combinational drug resistant antibacterial therapy and even antitumor therapy.展开更多
基金supported by the National Natural Science Foundation of China(22122111,92256304)the Ministry of Science and Technology of China(2022YFA1204401)。
文摘This study optimized the TADF feature of axial chiral enantiomers through precise donor engineering,and multicolor CP-TADFwas achieved in the axial chiral framework.Three pairs of axial enantiomers with donor-regulated TADF feature,namely(R/S)-TPCBD,(R/S)-DPCBD,and(R/S)-DPACBD,were synthesized by introducing carbazole donors with different substituents onto biphenyl cyanide acceptors.As the electron-donating ability of donors increases,the emission of these axial enantiomers ranges from 455,476 to 552 nm,their singlet-triplet energy gaps(ΔE_(ST))gradually decrease from 0.30,0.22 to 0.02 e V,accompanied by an increasement in the transition rate(k_(RISC))of RISC process,and the k_(RISC)of DPACBD could reach up to 7.16×10^(5)s^(-1).These axial enantiomers also exhibit mirror-image CD and circularly polarized luminescence(CPL)properties.Moreover,OLEDs based on TPCBD,DPCBD,and DPACBD as emitter were then fabricated,which displayed blue,green,and orange electroluminescence with EQE_(max)of 13.0%,16.4%,and 25.0%,respectively.The results also exhibited a phenomenon of device efficiency increasing with the enhancement of donor abilities.Notably,the CP-OLEDs using(R/S)-TPCBD,(R/S)-DPCBD and(R/S)-DPACBD as emitters displayed intense CPEL signals with g_(EL)values of 3.4×10^(-3)/-4.1×10^(-3),3.2×10^(-3)/-3.1×10^(-3)and2.3×10^(-3)/-2.1×10^(-3),respectively.By convenient molecular engineering of donor regulation in the same molecular skeleton,CP-TADF materials with multicolor CPEL and improved device performance could be conveniently achieved.
基金the National Natural Science Foundation of China(Nos.21977065,22177065 and 21807067)Sanjin Scholars Support Planunder Special Funding(No.2017-06)+2 种基金Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(Nos.201802106,2019L0022)Supported by the Fund for Shanxi“1331”Project(1331)the Program for Introducing Overseas High-level Talents of Shanxi(Hundred Talents Plan)。
文摘It is of great significance to develop effective antibacterial agents and methods to combat drug resistant bacterial infections due to its increasing threaten to human health and the ineffectiveness of antibiotics.Herein,a multifunctional hybrid nano-assembly(M1-Fe NPs)based on conjugated oligomer and ferrous ion was engineered with favorable bactericidal activity for synergetic antibacterial therapy.The chelation of ferrous ion not only enhances the photothermal conversion efficiency of M1 but also endows the nano-assembly with catalytic capability of transferring H_(2)O_(2) into stronger oxidant hydroxyl radicals(·OH).Meanwhile,the generated heat can further promote the Fenton reaction activity.By generating cytotoxic heat and oxidative·OH,M1-Fe NPs can effectively kill Staphylococcus aureus in vitro and in vivo with the aid of low dosage of H_(2)O_(2).The work provides a new multifunctional platform for combinational drug resistant antibacterial therapy and even antitumor therapy.
