A novel macrocycle based on conformation-adaptive and electron-rich dihydrophenazine was designed and synthesized.On the one hand,the macrocycle showed host-guest interactions with tetracyanoquinodimethane(TCNQ)drivin...A novel macrocycle based on conformation-adaptive and electron-rich dihydrophenazine was designed and synthesized.On the one hand,the macrocycle showed host-guest interactions with tetracyanoquinodimethane(TCNQ)driving by charge transfer interaction between them.Meanwhile,host-guest complexation was accompanied by fluorescence quenching and conformational change of the macrocycle.On the other hand,the oxidation of the macrocycle resulted in its diradical cation analogue and induced the release of the guest molecule TCNQ,thereby accomplishing reversible binding dynamics.Therefore,this work wellillustrates the chemical and structural versatility of dihydrophenazine in the synthesis of macrocycles and their host-guest chemistry.展开更多
Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semico...Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semiconductors,such as high exciton binding energy and poor ambipolar charge mobility. While this adversely causes tremendous non-radiative charge recombination and instability issues,which currently become the most critical limits for commercialization of OPVs. Here,we present a concept-to-proof study on the potential of D:A heterojunction free OPV by taking advantage of recent progress of non-fullerene acceptors. First,we demonstrate that the “free carriers” can be spontaneously generated upon illumination in an NFA,i.e.,the 6TIC-4F single layer. Second,the 6TIC-4F layer also exhibits good ambipolar charge transporting property. These exceptional characteristics distinguish it from the traditional organic semiconductors,and relieve it from the reliance of D:A heterojunction to independently work as active layer. As a result,the subsequent OPV by simply sandwiching the 6TIC-4F layer between the cathode and anode yields a considerably high power conversion efficiency ~1%. Moreover,we find the D:A heterojunction free device exhibits two order of magnitude higher electroluminescence quantum efficiency and significantly reduced VOC loss by 0.16 eV compared to those of the D:A BHJ structure,validating its promise for higher efficiency in the future. Therefore,our work demonstrates the possibility of using D:A heterojunction-free device structure for high performance,that can potentially become the next game changer of OPV.展开更多
Recently,solution-processed organic solar cells combining small-molecule donor and nonfullerene acceptor have achieved breakthrough results with the certified efficiency over 15%.These impressive progresses are driven...Recently,solution-processed organic solar cells combining small-molecule donor and nonfullerene acceptor have achieved breakthrough results with the certified efficiency over 15%.These impressive progresses are driven by the concerted efforts of modifying the donor and acceptor materials and optimizing the morphology.Considering the defined chemical structures and easily tuned properties of small-molecule materials,it is of great necessity and importance to pay more attentions on the topic of all-small molecule organic solar cells.Here,we summarize the recent progress of all-small molecule organic solar cells from the prospect of materials'evolutions and expect to provide some hints for its future developments.The involved small-molecule donors including oligothiophene-,benzodithiophene-,naphthodithiophene-,and porphyrin-based materials are discussed to illustrate the relationship of chemical structures,properties,and device performance.Then,the small-molecule nonfullerene acceptors in all-small molecules organic solar cells are discussed to highlight their vital role.Finally,we will present the challenges and future of this research area.展开更多
Triphenylamine(TPA)derivatives and their radical cation counterparts have successfully demonstrated a great potential for applications in a wide range of fields including organic redox catalysis,organic semiconductors...Triphenylamine(TPA)derivatives and their radical cation counterparts have successfully demonstrated a great potential for applications in a wide range of fields including organic redox catalysis,organic semiconductors,magnetic materials,etc.,mainly because of their excellent redox activity.The stability of TPA radical cation has significant effect on the properties of the TPA-based functional materials,especially in relation to their electronic properties.Considering the instability of parent TPA radical cation,many efforts have been devoted to the development of stable TPA radical cations and related materials.Among them,TPA radical cation-based macrocycles have attracted particular attention because their large delocalized structures can stabilize the TPA radicals,thus endow them with outstanding redox behaviors,multiple resonance structures,and wide application in various optoelectronic devices.In this review,we give a brief introduction of organic radicals and the documented stable TPA radicals.Subsequently,a number of TPA radical cation-based macrocycles are comprehensively surveyed.It is expected that this minireview will not only summarize the recent development of TPA radical cations and their macrocycles,but also shed new light on the prospect of the design of more sophisticated radical cation-based architectures and related materials.展开更多
An unexpected bistricyclic aromatic ene AF was synthesized in a tin(Ⅱ)chloride-mediated reductive aromatization reaction.The obtained AF showed a highly overcrowded structural conformation as revealed by X-ray crysta...An unexpected bistricyclic aromatic ene AF was synthesized in a tin(Ⅱ)chloride-mediated reductive aromatization reaction.The obtained AF showed a highly overcrowded structural conformation as revealed by X-ray crystallography.Interestingly,AF exhibited reversible high-contrast mechanochromism and thermochromism between pale and red color.The obvious chromism is likely ascribed to the conformation transformation and trace amount of diradical species formation upon stimulus.展开更多
The design and construction of highly effective circularly polarized luminescence(CPL)-active materials has aroused considerable attention due to their widespread applications in sensors,optical devices,and asymmetric...The design and construction of highly effective circularly polarized luminescence(CPL)-active materials has aroused considerable attention due to their widespread applications in sensors,optical devices,and asymmetric synthesis.However,the exploration of novel CPL-active materials with high luminescence dissymmetry factor(glum)values is still a challenge.Herein,we describe a new approach for the preparation of supramolecular metallacycles with amplified CPL promoted by hierarchical self-assembly involving Pt···Pt interactions.Notably,the resultant metallacycles exhibited strong CPL signals with high glum values,while their corresponding precursors were CPL silent.The CPL amplification mechanism was comprehensively validated by ultravioletvisible absorption,emission spectroscopy,nuclear magnetic resonance spectroscopy,scanning electron microscopy,transmission electron microscopy,atomic force microscopy,coarse-grained molecular dynamics simulations,and timedependent density functional theory calculations.This work thus provides the first example of preparing highly effective CPL-active materials based on hierarchical self-assembly involving Pt···Pt interactions.展开更多
Triphenylamine(TPA) derivatives have been widely used as useful building blocks for diverse functional materials because of their excellent redox activity. Most of the molecular structures of TPA-based organic functio...Triphenylamine(TPA) derivatives have been widely used as useful building blocks for diverse functional materials because of their excellent redox activity. Most of the molecular structures of TPA-based organic functional materials contain 4-anisyl groups, which on one hand could reduce their oxidation potential and on the other hand significantly delocalize the spin density of the resultant TPA radical cation species and enhance their stability. However, molecular-level investigation of the redox behavior of triphenylamines consisting of 4-anisyl group and the electronic structures of their radical cation species has not been reported in the literature. Herein, we design a series of triphenylamines consisting of one, two, or three 3,5-di–tert–butyl–4-anisyl groups and investigate their redox behaviors and corresponding radical cation species. We disclose that the resonance hybrid and steric protection could both contribute to the stability of triphenylamine radical cations. Moreover, further oxidation leads to an unexpected oxidative demethylation. The findings in this work may reveal new insights for the understanding of the unique redox properties of 4-anisyl substituted triphenylamines.展开更多
基金supported by the NSFC,China(No.22071061)the Shanghai Natural Science Foundation(No.22ZR1420600).
文摘A novel macrocycle based on conformation-adaptive and electron-rich dihydrophenazine was designed and synthesized.On the one hand,the macrocycle showed host-guest interactions with tetracyanoquinodimethane(TCNQ)driving by charge transfer interaction between them.Meanwhile,host-guest complexation was accompanied by fluorescence quenching and conformational change of the macrocycle.On the other hand,the oxidation of the macrocycle resulted in its diradical cation analogue and induced the release of the guest molecule TCNQ,thereby accomplishing reversible binding dynamics.Therefore,this work wellillustrates the chemical and structural versatility of dihydrophenazine in the synthesis of macrocycles and their host-guest chemistry.
基金supported by the National Key Research and Development Program of China(No.2022YFB4200600)the National Natural Science Foundation of China(Nos.52173185 and 52127806)+1 种基金the Fundamental Research Funds for the Central Universities(Nos.226-2022-00133 and 226-2022-00209)L.Z.thanks the research start-up fund from Zhejiang University.
文摘Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semiconductors,such as high exciton binding energy and poor ambipolar charge mobility. While this adversely causes tremendous non-radiative charge recombination and instability issues,which currently become the most critical limits for commercialization of OPVs. Here,we present a concept-to-proof study on the potential of D:A heterojunction free OPV by taking advantage of recent progress of non-fullerene acceptors. First,we demonstrate that the “free carriers” can be spontaneously generated upon illumination in an NFA,i.e.,the 6TIC-4F single layer. Second,the 6TIC-4F layer also exhibits good ambipolar charge transporting property. These exceptional characteristics distinguish it from the traditional organic semiconductors,and relieve it from the reliance of D:A heterojunction to independently work as active layer. As a result,the subsequent OPV by simply sandwiching the 6TIC-4F layer between the cathode and anode yields a considerably high power conversion efficiency ~1%. Moreover,we find the D:A heterojunction free device exhibits two order of magnitude higher electroluminescence quantum efficiency and significantly reduced VOC loss by 0.16 eV compared to those of the D:A BHJ structure,validating its promise for higher efficiency in the future. Therefore,our work demonstrates the possibility of using D:A heterojunction-free device structure for high performance,that can potentially become the next game changer of OPV.
基金the financial support from the Office of Naval Research(N00014-17-1-2260 and N00014-20-1-2191).
文摘Recently,solution-processed organic solar cells combining small-molecule donor and nonfullerene acceptor have achieved breakthrough results with the certified efficiency over 15%.These impressive progresses are driven by the concerted efforts of modifying the donor and acceptor materials and optimizing the morphology.Considering the defined chemical structures and easily tuned properties of small-molecule materials,it is of great necessity and importance to pay more attentions on the topic of all-small molecule organic solar cells.Here,we summarize the recent progress of all-small molecule organic solar cells from the prospect of materials'evolutions and expect to provide some hints for its future developments.The involved small-molecule donors including oligothiophene-,benzodithiophene-,naphthodithiophene-,and porphyrin-based materials are discussed to illustrate the relationship of chemical structures,properties,and device performance.Then,the small-molecule nonfullerene acceptors in all-small molecules organic solar cells are discussed to highlight their vital role.Finally,we will present the challenges and future of this research area.
基金the Innovation Program of Shanghai Municipal Education Commission(No.2019-01-07-00-05-E00012)Program for Changjiang Scholars and Innovative Research Team in University for financial support+2 种基金the financial supports sponsored by NSFC/China(Nos.22071061,52003081)Shanghai Sailing Program(No.19YF1412900)Microscale Magnetic Resonance Platform of ECNU.
文摘Triphenylamine(TPA)derivatives and their radical cation counterparts have successfully demonstrated a great potential for applications in a wide range of fields including organic redox catalysis,organic semiconductors,magnetic materials,etc.,mainly because of their excellent redox activity.The stability of TPA radical cation has significant effect on the properties of the TPA-based functional materials,especially in relation to their electronic properties.Considering the instability of parent TPA radical cation,many efforts have been devoted to the development of stable TPA radical cations and related materials.Among them,TPA radical cation-based macrocycles have attracted particular attention because their large delocalized structures can stabilize the TPA radicals,thus endow them with outstanding redox behaviors,multiple resonance structures,and wide application in various optoelectronic devices.In this review,we give a brief introduction of organic radicals and the documented stable TPA radicals.Subsequently,a number of TPA radical cation-based macrocycles are comprehensively surveyed.It is expected that this minireview will not only summarize the recent development of TPA radical cations and their macrocycles,but also shed new light on the prospect of the design of more sophisticated radical cation-based architectures and related materials.
基金Innovation Program of Shanghai Municipal Education Commission(No.2019-01-07-00-05-E00012)Program for Changjiang Scholars and Innovative Research Team in University for financial support+1 种基金the financial supports sponsored by Shanghai Sailing Program(No.19YF1412900)the Fundamental Research Funds for the Central Universities。
文摘An unexpected bistricyclic aromatic ene AF was synthesized in a tin(Ⅱ)chloride-mediated reductive aromatization reaction.The obtained AF showed a highly overcrowded structural conformation as revealed by X-ray crystallography.Interestingly,AF exhibited reversible high-contrast mechanochromism and thermochromism between pale and red color.The obvious chromism is likely ascribed to the conformation transformation and trace amount of diradical species formation upon stimulus.
基金supported by the National Natural Science Foundation of China(21922506,21871092,and 21603074)Shanghai Pujiang Program(18PJD015)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Austrian Science Fund(M 2709-N28)for the financial support。
文摘The design and construction of highly effective circularly polarized luminescence(CPL)-active materials has aroused considerable attention due to their widespread applications in sensors,optical devices,and asymmetric synthesis.However,the exploration of novel CPL-active materials with high luminescence dissymmetry factor(glum)values is still a challenge.Herein,we describe a new approach for the preparation of supramolecular metallacycles with amplified CPL promoted by hierarchical self-assembly involving Pt···Pt interactions.Notably,the resultant metallacycles exhibited strong CPL signals with high glum values,while their corresponding precursors were CPL silent.The CPL amplification mechanism was comprehensively validated by ultravioletvisible absorption,emission spectroscopy,nuclear magnetic resonance spectroscopy,scanning electron microscopy,transmission electron microscopy,atomic force microscopy,coarse-grained molecular dynamics simulations,and timedependent density functional theory calculations.This work thus provides the first example of preparing highly effective CPL-active materials based on hierarchical self-assembly involving Pt···Pt interactions.
基金financially supported by the National Natural Science Foundation of China (Nos. 22071061 and 52003081)Shanghai Sailing Pro-gram (No. 19YF1412900)Microscale Magnetic Resonance Platform of ECNU。
文摘Triphenylamine(TPA) derivatives have been widely used as useful building blocks for diverse functional materials because of their excellent redox activity. Most of the molecular structures of TPA-based organic functional materials contain 4-anisyl groups, which on one hand could reduce their oxidation potential and on the other hand significantly delocalize the spin density of the resultant TPA radical cation species and enhance their stability. However, molecular-level investigation of the redox behavior of triphenylamines consisting of 4-anisyl group and the electronic structures of their radical cation species has not been reported in the literature. Herein, we design a series of triphenylamines consisting of one, two, or three 3,5-di–tert–butyl–4-anisyl groups and investigate their redox behaviors and corresponding radical cation species. We disclose that the resonance hybrid and steric protection could both contribute to the stability of triphenylamine radical cations. Moreover, further oxidation leads to an unexpected oxidative demethylation. The findings in this work may reveal new insights for the understanding of the unique redox properties of 4-anisyl substituted triphenylamines.