Ionically bonded organic metal halide perovskite-like luminescent materials,which incorporate organic cations and metal halides,have emerged as a versatile multicomponent material system.However,these materials still ...Ionically bonded organic metal halide perovskite-like luminescent materials,which incorporate organic cations and metal halides,have emerged as a versatile multicomponent material system.However,these materials still face challenges in terms of low phosphorescence quantum yields and limited long persistent luminescence(LPL)colors.Herein,we present the design and synthesis of an intraligand chargetransfer organic-based metal halide perovskite-like material,in which organic cations form a compact supramolecular hydrogen-bonded organic framework(HOF)structure,exhibiting crystallization-induced phosphorescence emission of ligand,while metal halides form a unique two-dimensional(2D)structure that displays intrinsic self-trapped excitons(STE)emission under the radiation of UV light.Notably,the metal halide hybrid is found to exhibit enhanced phosphorescent photoluminescence efficiency of up to 81.05%and tunable LPL from cyan to orange compared to the pristine organic phosphor,due to the structural distortion and scaffolding effects of 2D metal halides as well as a well-packed HOF structure.Optical characterizations and theoretical calculations reveal that charge transfer from organic cations and halogen to ligand as well as STE from inorganic layers are responsible for the tunable LPL.Meanwhile,the high-efficiency phosphorescent quantum yield is attributed to stronger hydrogen bond stacking as well as structural distortion of metal halogen bands.Thus,the obtained LPL provides potentials in anti-counterfeiting,security systems,and so on.展开更多
Three isomorphic ionic bismuth(Ⅲ)halides were synthesized,utilizing 2,2’-bipyridyl-1,1’-dioxide(bp2do)as the organic ligand decorated on the halobismuthate(Ⅲ)moieties,namely,[Ammim][BiBr_(4)(bp2do)](1,Ammim=1-ally...Three isomorphic ionic bismuth(Ⅲ)halides were synthesized,utilizing 2,2’-bipyridyl-1,1’-dioxide(bp2do)as the organic ligand decorated on the halobismuthate(Ⅲ)moieties,namely,[Ammim][BiBr_(4)(bp2do)](1,Ammim=1-allyl-2,3-dimethylimidazolium),[Ammim][BiCl_(4)(bp2do)](2)and[Amim][BiCl_(4)(bp2do)](3,Amim=1-allyl-3-methylimidazolium).They all crystallize in the space group of Pca2_(1)with a similar supramolecular packing mode.However,the average adjacent Bi–Bi distances are slightly different,that is 1>2>3.Moreover,they possess different phosphorescence quantum yields(QYs)with 0.38%for 1,27.83%for 2 and 34.76%for 3.Note that the QY of 3 remains the highest for bp2do-based halobismuthate hybrids.Their phosphorescence originates from the organic ligand bp2do,in which an inorganic-to-organic charge transfer(IOCT)process exists,as confirmed by density functional theory(DFT)calculations.The three compounds possess X-ray scintillation properties.Eventually,a WLED could be fabricated by mixing commercial nitride red phosphor with cyan-emitting 3.This study provides a method for the synthesis of organic ligand based ionic bismuth halide hybrids with higher QYs,and enriches X-ray scintillation materials.展开更多
In recent years,cyclometalated Pt(Ⅱ)complexes with a terdentate ligand have been used as prospective blue phosphorescent materials.For improving these materials further,the introduction of o-carborane is treated as a...In recent years,cyclometalated Pt(Ⅱ)complexes with a terdentate ligand have been used as prospective blue phosphorescent materials.For improving these materials further,the introduction of o-carborane is treated as an excellent strategy to promote the luminescence efficiency.A series of new materials show over 82%phosphorescence quantum yield and good stability,but they are still not fully elucidated.In this work,several different stable o-carborane cages are introduced into the traditional C,N,C-cyclometalated Pt(Ⅱ)complexes in order to explore their influence completely in contrast to the original phenyl ligand from the view of theoretical investigation.Comprehensive analyses of the geometric structure,molecular orbital and configuration information,spin-orbit coupling elements,vibrational modes,etc.have been carried out.More importantly,our theoretical model highlights that the embedded o-carborane ligands will have an impact on the photophysical properties and quantum efficiency of these Pt(Ⅱ)complexes significantly,which can provide a valuable guideline for designing and regulating several aspects of highly efficient blue phosphorescent materials.展开更多
A series of 2-phenylpyridine(ppy)-type cyclometalating ligands containing rigid 5,9-dioxa-13bboranaphtho[3,2,1-de]anthracene(OBA)units have been developed.Together with different ppy-type cyclometalating ligands with ...A series of 2-phenylpyridine(ppy)-type cyclometalating ligands containing rigid 5,9-dioxa-13bboranaphtho[3,2,1-de]anthracene(OBA)units have been developed.Together with different ppy-type cyclometalating ligands with a phenylsulfonyl group(–SO_(2)Ph)substituted at different positions,new unsymmetric heteroleptic cyclometalated Ir(Ⅲ)complexes have been successfully synthesized.Their photophysical,electrochemical and electroluminescence(EL)behaviors have been fully characterized.In addition,both time-dependent functional theory(TD-DFT)and natural transition orbital(NTO)theoretical results have been obtained to gain insight into the optoelectronic behaviors of these unsymmetric Ir(Ⅲ)complexes with OBA units.The NTO results indicate that the features of the lowest triplet excited states(T_(1))can be delicately tuned by combination between the OBA-based cyclometalating ligand and another ppy-type ligand with the–SO_(2)Ph group.Importantly,these unsymmetric Ir(Ⅲ)complexes can exhibit very high phosphorescence quantum yield(Φ_(p))higher than 0.90 due to the highly rigid OBA unit which can effectively restrain non-radiative processes.In addition,an electron injection/transporting(EI/ET)ability can be conferred to these unsymmetric heteroleptic cyclometalated Ir(Ⅲ)complexes by both OBA and–SO_(2)Ph moieties.Taking advantage of these merits,organic light-emitting diodes(OLEDs)based on these unsymmetric heteroleptic cyclometalated Ir(Ⅲ)complexes can show a high maximum external quantum efficiency(ηext)of 12.8%,a current efficiency(η_(L))of 51.1 cd A^(−1),and a power efficiency(η_(P))of 40.5 lm W^(−1) for a yellowish-green device,while EL efficiencies for red devices are 6.8%,13.9 cd A^(−1),and 12.8 lm W^(−1),respectively.All these results indicate the good potential of the rigid OBA unit in developing functional phosphorescent emitters.展开更多
基金National Natural Science Foundation of China,Grant/Award Numbers:22101162,92261114。
文摘Ionically bonded organic metal halide perovskite-like luminescent materials,which incorporate organic cations and metal halides,have emerged as a versatile multicomponent material system.However,these materials still face challenges in terms of low phosphorescence quantum yields and limited long persistent luminescence(LPL)colors.Herein,we present the design and synthesis of an intraligand chargetransfer organic-based metal halide perovskite-like material,in which organic cations form a compact supramolecular hydrogen-bonded organic framework(HOF)structure,exhibiting crystallization-induced phosphorescence emission of ligand,while metal halides form a unique two-dimensional(2D)structure that displays intrinsic self-trapped excitons(STE)emission under the radiation of UV light.Notably,the metal halide hybrid is found to exhibit enhanced phosphorescent photoluminescence efficiency of up to 81.05%and tunable LPL from cyan to orange compared to the pristine organic phosphor,due to the structural distortion and scaffolding effects of 2D metal halides as well as a well-packed HOF structure.Optical characterizations and theoretical calculations reveal that charge transfer from organic cations and halogen to ligand as well as STE from inorganic layers are responsible for the tunable LPL.Meanwhile,the high-efficiency phosphorescent quantum yield is attributed to stronger hydrogen bond stacking as well as structural distortion of metal halogen bands.Thus,the obtained LPL provides potentials in anti-counterfeiting,security systems,and so on.
基金supported by the National Natural Science Foundation of China(No.21601181)the Natural Science Foundation of Fujian Province(No.2020J01118).
文摘Three isomorphic ionic bismuth(Ⅲ)halides were synthesized,utilizing 2,2’-bipyridyl-1,1’-dioxide(bp2do)as the organic ligand decorated on the halobismuthate(Ⅲ)moieties,namely,[Ammim][BiBr_(4)(bp2do)](1,Ammim=1-allyl-2,3-dimethylimidazolium),[Ammim][BiCl_(4)(bp2do)](2)and[Amim][BiCl_(4)(bp2do)](3,Amim=1-allyl-3-methylimidazolium).They all crystallize in the space group of Pca2_(1)with a similar supramolecular packing mode.However,the average adjacent Bi–Bi distances are slightly different,that is 1>2>3.Moreover,they possess different phosphorescence quantum yields(QYs)with 0.38%for 1,27.83%for 2 and 34.76%for 3.Note that the QY of 3 remains the highest for bp2do-based halobismuthate hybrids.Their phosphorescence originates from the organic ligand bp2do,in which an inorganic-to-organic charge transfer(IOCT)process exists,as confirmed by density functional theory(DFT)calculations.The three compounds possess X-ray scintillation properties.Eventually,a WLED could be fabricated by mixing commercial nitride red phosphor with cyan-emitting 3.This study provides a method for the synthesis of organic ligand based ionic bismuth halide hybrids with higher QYs,and enriches X-ray scintillation materials.
基金supported by the State Key Development Program for Basic Research of China(Grant No.2013CB834801)the Natural Science Foundation of China(Grant No.21573088)+1 种基金the Young Scholar Training Program of Jilin Universitythe Open Project Funding of Beijing National Laboratory for Molecular Sciences(BNLMS).
文摘In recent years,cyclometalated Pt(Ⅱ)complexes with a terdentate ligand have been used as prospective blue phosphorescent materials.For improving these materials further,the introduction of o-carborane is treated as an excellent strategy to promote the luminescence efficiency.A series of new materials show over 82%phosphorescence quantum yield and good stability,but they are still not fully elucidated.In this work,several different stable o-carborane cages are introduced into the traditional C,N,C-cyclometalated Pt(Ⅱ)complexes in order to explore their influence completely in contrast to the original phenyl ligand from the view of theoretical investigation.Comprehensive analyses of the geometric structure,molecular orbital and configuration information,spin-orbit coupling elements,vibrational modes,etc.have been carried out.More importantly,our theoretical model highlights that the embedded o-carborane ligands will have an impact on the photophysical properties and quantum efficiency of these Pt(Ⅱ)complexes significantly,which can provide a valuable guideline for designing and regulating several aspects of highly efficient blue phosphorescent materials.
基金supported by the National Natural Science Foundation of China(21572176,21875179,21602170 and 51803163)the Natural Science Foundation of Shaanxi Province(2019JZ-29 and 2019JQ-188)+3 种基金the China Postdoctoral Science Foundation(2016M600778)the Shaanxi Province Postdoctoral Science Foundation(2017BSHEDZZ03)the Fundamental Research Funds for the Central Universities(xjj2017099,xjj2016061 and cxtd2015003)the Key Laboratory Construction Program of Xi’an Municipal Bureau of Science and Technology(201805056ZD7CG40).
文摘A series of 2-phenylpyridine(ppy)-type cyclometalating ligands containing rigid 5,9-dioxa-13bboranaphtho[3,2,1-de]anthracene(OBA)units have been developed.Together with different ppy-type cyclometalating ligands with a phenylsulfonyl group(–SO_(2)Ph)substituted at different positions,new unsymmetric heteroleptic cyclometalated Ir(Ⅲ)complexes have been successfully synthesized.Their photophysical,electrochemical and electroluminescence(EL)behaviors have been fully characterized.In addition,both time-dependent functional theory(TD-DFT)and natural transition orbital(NTO)theoretical results have been obtained to gain insight into the optoelectronic behaviors of these unsymmetric Ir(Ⅲ)complexes with OBA units.The NTO results indicate that the features of the lowest triplet excited states(T_(1))can be delicately tuned by combination between the OBA-based cyclometalating ligand and another ppy-type ligand with the–SO_(2)Ph group.Importantly,these unsymmetric Ir(Ⅲ)complexes can exhibit very high phosphorescence quantum yield(Φ_(p))higher than 0.90 due to the highly rigid OBA unit which can effectively restrain non-radiative processes.In addition,an electron injection/transporting(EI/ET)ability can be conferred to these unsymmetric heteroleptic cyclometalated Ir(Ⅲ)complexes by both OBA and–SO_(2)Ph moieties.Taking advantage of these merits,organic light-emitting diodes(OLEDs)based on these unsymmetric heteroleptic cyclometalated Ir(Ⅲ)complexes can show a high maximum external quantum efficiency(ηext)of 12.8%,a current efficiency(η_(L))of 51.1 cd A^(−1),and a power efficiency(η_(P))of 40.5 lm W^(−1) for a yellowish-green device,while EL efficiencies for red devices are 6.8%,13.9 cd A^(−1),and 12.8 lm W^(−1),respectively.All these results indicate the good potential of the rigid OBA unit in developing functional phosphorescent emitters.
