Spin-orbit,charge-transfer intersystem crossing(SOCT-ISC)can directly overcome the disadvantages of the traditional heavy-atom effect and improve the generation efficiency of reactive oxygen species(ROS).Since orthogo...Spin-orbit,charge-transfer intersystem crossing(SOCT-ISC)can directly overcome the disadvantages of the traditional heavy-atom effect and improve the generation efficiency of reactive oxygen species(ROS).Since orthogonal molecular orbitals of donor-acceptor(D-A)pairs favor the SOCT-ISC transition,herein aza-borondipyrromethenes(aza-BODIPYs)with 1,7-di-anthracyl groups(An-azaBDP)was successfully prepared,owing to steric hindrance to produce a big dihedral angle between the two molecular orbital(MO)planes.Moreover,according to density functional theory(DFT)and time-dependent density functional theory(TDDFT),the energy difference between the S1-T1orbitals of An-aza BDP is small and more inclined towards ISC.An-aza BDP can effectively generate singlet oxygen under light irradiation.An-aza BDP with light irradiation can induce apoptosis in SW620 cells,and can serve as a potential candidate for the treatment of cancer cells and tumors.展开更多
Structural modifications are a successful and commonly used approach to tune the emission properties of diverse fluorophores,but extending this approach to heavy-atom-free persistent luminophores has so far been unsuc...Structural modifications are a successful and commonly used approach to tune the emission properties of diverse fluorophores,but extending this approach to heavy-atom-free persistent luminophores has so far been unsuccessful.Here we employed a novel strategy to demonstrate triplet–triplet energy transfer from an organic room-temperature phosphor(RTP)with persistent luminescence to an organic molecule with thermally activated delayed fluorescence(TADF).We illustrated this approach by preparing heavy-atom-free composite crystals of an RTP with a long-lifetime emission and a red emissive organic fluorophore with TADF to yield materials with emission above 650 nm.The emission arose from the triplet excited state of an acceptor undergoing thermally activated reverse intersystem crossing(RISC)to the emissive S1 state.Such composite crystal is the first organic material with persistent TADF,achieved by triplet–triplet energy transfer.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22078201,U1908202)Liaoning&Shenyang Key Laboratory of Functional Dye and Pigment(Nos.2021JH13/10200018,21–104–0–23)。
文摘Spin-orbit,charge-transfer intersystem crossing(SOCT-ISC)can directly overcome the disadvantages of the traditional heavy-atom effect and improve the generation efficiency of reactive oxygen species(ROS).Since orthogonal molecular orbitals of donor-acceptor(D-A)pairs favor the SOCT-ISC transition,herein aza-borondipyrromethenes(aza-BODIPYs)with 1,7-di-anthracyl groups(An-azaBDP)was successfully prepared,owing to steric hindrance to produce a big dihedral angle between the two molecular orbital(MO)planes.Moreover,according to density functional theory(DFT)and time-dependent density functional theory(TDDFT),the energy difference between the S1-T1orbitals of An-aza BDP is small and more inclined towards ISC.An-aza BDP can effectively generate singlet oxygen under light irradiation.An-aza BDP with light irradiation can induce apoptosis in SW620 cells,and can serve as a potential candidate for the treatment of cancer cells and tumors.
基金This study was financially supported by the National Natural Science Foundation of China(nos.21525206 and 21971023)Q.-Z.Y.and by the EPSRC Early Career Fellowship(no.EP/L000075/1)to R.B.
文摘Structural modifications are a successful and commonly used approach to tune the emission properties of diverse fluorophores,but extending this approach to heavy-atom-free persistent luminophores has so far been unsuccessful.Here we employed a novel strategy to demonstrate triplet–triplet energy transfer from an organic room-temperature phosphor(RTP)with persistent luminescence to an organic molecule with thermally activated delayed fluorescence(TADF).We illustrated this approach by preparing heavy-atom-free composite crystals of an RTP with a long-lifetime emission and a red emissive organic fluorophore with TADF to yield materials with emission above 650 nm.The emission arose from the triplet excited state of an acceptor undergoing thermally activated reverse intersystem crossing(RISC)to the emissive S1 state.Such composite crystal is the first organic material with persistent TADF,achieved by triplet–triplet energy transfer.
