The rapid development of low-bandgap(LBG)nonfullerene acceptors and wide-bandgap(WBG)copolymer donors in recent years has boosted the power conversion efficiency(PCE)of organic solar cells(OSCs)to the 18%level[1−21].T...The rapid development of low-bandgap(LBG)nonfullerene acceptors and wide-bandgap(WBG)copolymer donors in recent years has boosted the power conversion efficiency(PCE)of organic solar cells(OSCs)to the 18%level[1−21].The commercialization of OSCs is highly expected.However,critical issues like the cost and the stability also determine whether OSCs can enter the market or not[22].展开更多
The development of highly efficient thermally activated delayed fluorescence(TADF)emitters is persistently pursued for the application of organic light-emitting diodes(OLED)in full-colour display and solid-state light...The development of highly efficient thermally activated delayed fluorescence(TADF)emitters is persistently pursued for the application of organic light-emitting diodes(OLED)in full-colour display and solid-state lighting.Herein,we present a heptagonal intramolecular-lock strategy to design high-performance TADF emitters.As a proof-of-concept,a new type of tribenzotropone(TBP)acceptor has been designed and synthesized by a cascade decarboxylative cyclization of aryl oxoacetic acid derivative with biphenyl boronic acid.Compared with the unlocked benzophenone(BP)acceptor,the TBP acceptor has a highly twisted heptagonal geometry with moderate rigidity and flexibility,which enables a high-performance TADF emitter with a small single-triplet energy gap(ΔE_(ST))of 0.04 e V,a high photoluminescence quantum yield(Φ_(PL))of 99% and a large horizontal orientation factor(Θ_(//))of 84.0%.Consequently,highly efficient OLEDs with an external quantum efficiency as high as 33.8% are assembled,which is significantly higher than those of DPAC-BP with a highly rotatable BP acceptor(23.8%)as well as DPACFO with a rigid fluorenone(FO)acceptor(6.9%).展开更多
The control of excited states and related emissive properties of gold(Ⅲ)complexes mainly depends on the modulation of intramolecular electronic interactions among gold(Ⅲ)metal center,chelating ligands and/or periphe...The control of excited states and related emissive properties of gold(Ⅲ)complexes mainly depends on the modulation of intramolecular electronic interactions among gold(Ⅲ)metal center,chelating ligands and/or peripheral groups.However,luminescent gold(Ⅲ)systems based on intermolecular electronic interactions have never been explored.Here we report a series of proof-of-concept gold(Ⅲ)exciplexes using a simple gold(Ⅲ)complex,AuDPPy,as an electron acceptor.The emissive properties of gold(Ⅲ)exciplexes can be regulated by combining AuDPPy with different donors.Inspiringly,these gold(Ⅲ)exciplexes have donor-dependent emission mechanisms:dominant phosphorescence or dual radiative channels of thermally activated delayed fluorescence(TADF)and phosphorescence.Consequently,these gold(Ⅲ)exciplexes deliver green-to-red electroluminescence with external quantum efficiencies(EQEs)of up to 10.1%.More importantly,using these gold(Ⅲ)exciplexes to host multi-resonance TADF emitters results in narrowband yellow,orange,and deep-red electroluminescence with high EQEs of 23.5%,24.4%,and 27.4%,respectively,competitive to the highest values for gold(Ⅲ)OLEDs in similar color gamut.展开更多
Ohmic cathode contact can be formed readily via coordination-activated n-doping(CAN),by co-evaporating air-stable metals(e.g.,silver)and organic ligands with coordination sites.It has been proposed that increasing the...Ohmic cathode contact can be formed readily via coordination-activated n-doping(CAN),by co-evaporating air-stable metals(e.g.,silver)and organic ligands with coordination sites.It has been proposed that increasing the nucleophilicity of the main binding site of a ligand is essential for reducing the work function of the doped films.展开更多
The development and enrichment of high-performance organic fluorophores that simultaneously possess thermally activated delayed fluorescence(TADF)and aggregation-induced emission(AIE)properties is going pursued but re...The development and enrichment of high-performance organic fluorophores that simultaneously possess thermally activated delayed fluorescence(TADF)and aggregation-induced emission(AIE)properties is going pursued but remains a great challenge due to severe exciton quenching.Herein,a systematical investigation on imidazole moiety has successfully given rise to a series of highly efficient imidazolebased TADF-AIE luminogens for the first time.The attachment of two cyano functionalities on imidazole moiety can significantly increase the electron-withdrawing ability,so as to realize TADF emissions with small singlet-triplet energy gaps(ΔEST)values.Meanwhile,the installation of a steric hindrance group at N1 position of imidazole moiety can twist the geometry between imidazole and phenyl bridge,thus transforming imidazole derivative from an aggregation-caused quenching emitter into an AIE luminogen.Consequently,the non-doped organic light-emitting diodes(OLEDs)utilizing these TADF-AIE luminogens as emitters exhibit outstanding skyblue and green emissions,with external quantum efficiency(EQE)as high as 20.0%and low efficiency roll-off(EQE at 1000 cd m−2,16.1%).These values represent the state-of-the-art performance for all imidazole-based OLED devices,which illustrates the significant potential of imidazole derivatives in assembling high-performance OLEDs.展开更多
基金We thank the National Key Research and Development Program of China(2017YFA0206600)the National Natural Science Foundation of China(51773045,21772030,51922032,21961160720,62074022)+1 种基金Fundamental Research Funds for the Central Universities(2020CDJQY-A055)the Youth Association for Promoting Innovation(CAS)for financial support.
文摘The rapid development of low-bandgap(LBG)nonfullerene acceptors and wide-bandgap(WBG)copolymer donors in recent years has boosted the power conversion efficiency(PCE)of organic solar cells(OSCs)to the 18%level[1−21].The commercialization of OSCs is highly expected.However,critical issues like the cost and the stability also determine whether OSCs can enter the market or not[22].
基金supported by the National Natural Science Foundation of China(22275127,22031007,22005204)。
文摘The development of highly efficient thermally activated delayed fluorescence(TADF)emitters is persistently pursued for the application of organic light-emitting diodes(OLED)in full-colour display and solid-state lighting.Herein,we present a heptagonal intramolecular-lock strategy to design high-performance TADF emitters.As a proof-of-concept,a new type of tribenzotropone(TBP)acceptor has been designed and synthesized by a cascade decarboxylative cyclization of aryl oxoacetic acid derivative with biphenyl boronic acid.Compared with the unlocked benzophenone(BP)acceptor,the TBP acceptor has a highly twisted heptagonal geometry with moderate rigidity and flexibility,which enables a high-performance TADF emitter with a small single-triplet energy gap(ΔE_(ST))of 0.04 e V,a high photoluminescence quantum yield(Φ_(PL))of 99% and a large horizontal orientation factor(Θ_(//))of 84.0%.Consequently,highly efficient OLEDs with an external quantum efficiency as high as 33.8% are assembled,which is significantly higher than those of DPAC-BP with a highly rotatable BP acceptor(23.8%)as well as DPACFO with a rigid fluorenone(FO)acceptor(6.9%).
基金supported by the National Natural Science Foundation of China(52022071,52130308)Shenzhen Fundamental Research Program(JCYJ20190808151209557,ZDSYS20210623091813040)。
文摘The control of excited states and related emissive properties of gold(Ⅲ)complexes mainly depends on the modulation of intramolecular electronic interactions among gold(Ⅲ)metal center,chelating ligands and/or peripheral groups.However,luminescent gold(Ⅲ)systems based on intermolecular electronic interactions have never been explored.Here we report a series of proof-of-concept gold(Ⅲ)exciplexes using a simple gold(Ⅲ)complex,AuDPPy,as an electron acceptor.The emissive properties of gold(Ⅲ)exciplexes can be regulated by combining AuDPPy with different donors.Inspiringly,these gold(Ⅲ)exciplexes have donor-dependent emission mechanisms:dominant phosphorescence or dual radiative channels of thermally activated delayed fluorescence(TADF)and phosphorescence.Consequently,these gold(Ⅲ)exciplexes deliver green-to-red electroluminescence with external quantum efficiencies(EQEs)of up to 10.1%.More importantly,using these gold(Ⅲ)exciplexes to host multi-resonance TADF emitters results in narrowband yellow,orange,and deep-red electroluminescence with high EQEs of 23.5%,24.4%,and 27.4%,respectively,competitive to the highest values for gold(Ⅲ)OLEDs in similar color gamut.
基金supported by the National Key Basic Research and Development Program of China(2017YFA0204501,2016YFB0400702 and 2016YFB0401003)the National Natural Science Foundation of China(51525304 and 61890942)the Fundamental Research Funds for the Central Universities.
基金supported by the National Key Basic Research and Development Program of China (2017YFA0204501 and 2020YFA0715000)the National Natural Science Foundation of China (51903137 and 61890942)+1 种基金Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory (XHT2020-005)financial support from the Young Elite Scientist Sponsorship Program (2019QNRC001) by China Association for Science and Technology。
基金This work was supported by the National Natural Science Foundation of China(21432005)the Fundamental Research Funds for the Central Universities and the Comprehensive Training Platform Specialized Laboratory,College of Chemistry,Sichuan University。
基金supported by the National Key Basic Research and Development Program of China(grant no.2017YFA0204501)the National Science Fund of China(grant nos.U1601651,51903137,and 61890942)+2 种基金the Guangdong Major Project of Basic and Applied Basic Research(grant no.2019B030302009)the Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(grant no.XHT2020-005)the Young Elite Scientist Sponsorship Program for the financial support(grant no.2019QNRC001)by the China Association for Science and Technology。
文摘Ohmic cathode contact can be formed readily via coordination-activated n-doping(CAN),by co-evaporating air-stable metals(e.g.,silver)and organic ligands with coordination sites.It has been proposed that increasing the nucleophilicity of the main binding site of a ligand is essential for reducing the work function of the doped films.
基金National NSF of China,Grant/Award Numbers:22031007,22005204Sichuan Science and Technology Program,Grant/Award Numbers:2020YJ0245,2020YJ0302。
文摘The development and enrichment of high-performance organic fluorophores that simultaneously possess thermally activated delayed fluorescence(TADF)and aggregation-induced emission(AIE)properties is going pursued but remains a great challenge due to severe exciton quenching.Herein,a systematical investigation on imidazole moiety has successfully given rise to a series of highly efficient imidazolebased TADF-AIE luminogens for the first time.The attachment of two cyano functionalities on imidazole moiety can significantly increase the electron-withdrawing ability,so as to realize TADF emissions with small singlet-triplet energy gaps(ΔEST)values.Meanwhile,the installation of a steric hindrance group at N1 position of imidazole moiety can twist the geometry between imidazole and phenyl bridge,thus transforming imidazole derivative from an aggregation-caused quenching emitter into an AIE luminogen.Consequently,the non-doped organic light-emitting diodes(OLEDs)utilizing these TADF-AIE luminogens as emitters exhibit outstanding skyblue and green emissions,with external quantum efficiency(EQE)as high as 20.0%and low efficiency roll-off(EQE at 1000 cd m−2,16.1%).These values represent the state-of-the-art performance for all imidazole-based OLED devices,which illustrates the significant potential of imidazole derivatives in assembling high-performance OLEDs.
