Coinage metal_((I))complexes exhibiting thermally activated delayed fluorescence(TADF)have attracted worldwide attention as emitters for OLEDs.Reducing the emission lifetime and improving the quantum efficiency of suc...Coinage metal_((I))complexes exhibiting thermally activated delayed fluorescence(TADF)have attracted worldwide attention as emitters for OLEDs.Reducing the emission lifetime and improving the quantum efficiency of such emitters is a current challenge in this hot field.To address this issue(challenge),a symmetry-based design strategy has been applied herein to obtain pseudo-symmetric complexes[M_(2)(tdpb)(NHC)_(2)]^(2+)(M=Cu,Ag,Au)scaffolded by 1,2,4,5-tetrakis(diphenylphosphino)benzene(tdpb)and N-heterocyclic carbene(NHC)ligands.In the solid state at ambient temperature,the synthesized compounds exhibit cyan to yellow TADF of the metal-to-ligand charge transfer type with excellent quantum yields(58-89%)and short decay times(2.5-15μs).It is shown that the symmetry-based design strategy leads to a significant increase in the radiative rate constants for the“dimers”[M_(2)(tdpb)(NHC)_(2)]^(2+)compared to the“monomers”[M(dppb)(NHC)]^(+)based on 1,2-bis(diphenylphosphino)benzene(dppb).The practical potential of the developed TADF emitters was also demonstrated through their application as innovative thermo-and vapor-chromic emission inks for advanced anti-counterfeiting labels.展开更多
基金supported by Russian Science Foundation(Project 19-73-20196)the Russian Science Foundation(Project No.22-13-00077)for financial support of the computational part of this work and the Supercomputer Centre of Novosibirsk State University for the computational resources.
文摘Coinage metal_((I))complexes exhibiting thermally activated delayed fluorescence(TADF)have attracted worldwide attention as emitters for OLEDs.Reducing the emission lifetime and improving the quantum efficiency of such emitters is a current challenge in this hot field.To address this issue(challenge),a symmetry-based design strategy has been applied herein to obtain pseudo-symmetric complexes[M_(2)(tdpb)(NHC)_(2)]^(2+)(M=Cu,Ag,Au)scaffolded by 1,2,4,5-tetrakis(diphenylphosphino)benzene(tdpb)and N-heterocyclic carbene(NHC)ligands.In the solid state at ambient temperature,the synthesized compounds exhibit cyan to yellow TADF of the metal-to-ligand charge transfer type with excellent quantum yields(58-89%)and short decay times(2.5-15μs).It is shown that the symmetry-based design strategy leads to a significant increase in the radiative rate constants for the“dimers”[M_(2)(tdpb)(NHC)_(2)]^(2+)compared to the“monomers”[M(dppb)(NHC)]^(+)based on 1,2-bis(diphenylphosphino)benzene(dppb).The practical potential of the developed TADF emitters was also demonstrated through their application as innovative thermo-and vapor-chromic emission inks for advanced anti-counterfeiting labels.
