Since 2009,perovskite solar cells(PSCs)have advanced significantly,achieving over 26%efficiency for single-junction devices and exceeding 34%for silicon-perovskite tandem cells.Despite these successes,the weak adhesio...Since 2009,perovskite solar cells(PSCs)have advanced significantly,achieving over 26%efficiency for single-junction devices and exceeding 34%for silicon-perovskite tandem cells.Despite these successes,the weak adhesion of C_(60)to perovskite layers,due to van der Waals interactions,hinders long-term stability.In this study,we introduce electron-deficient intermolecular adhesives(EDIAs)as a novel interlayer material to enhance adhesion between perovskite and C_(60)layers.Comprehensive analyses,including density functional theory calculations,microscopy,and spectroscopy,demonstrate that EDIAs,particularly NDI-C9-Ace comprising of three key functionalities:aπ-electron-deficient arene core,a hydrophobic passivation core,and a secondary-bond anchoring core,significantly improve bonding strength and recombination passivation.This leads to enhanced efficiency as well as enhanced mechanical and photochemical stability in PSCs.Long-term stability tests further confirm the superior durability of EDIA-enhanced devices.This study highlights EDIA as a promising strategy for enhancing the robustness and efficiency of PSCs.展开更多
The efficient storage and release of H_(2)are pivotal for the advancement of hydrogen energy technologies.Cyclohexane,as a promising liquid organic hydrogen carrier(LOHC),provides a safe and practical solution for H_(...The efficient storage and release of H_(2)are pivotal for the advancement of hydrogen energy technologies.Cyclohexane,as a promising liquid organic hydrogen carrier(LOHC),provides a safe and practical solution for H_(2)storage.However,the performance limitations of dehydrogenation catalysts have hindered the rapid development of LOHC technology.In this study,we successfully developed boron-modified Pt/ZrO_(2)catalysts,which exhibit exceptional catalytic performance in cyclohexane dehydrogenation.The optimal boron content is determined to be 0.5 wt.%,with the Pt/0.5B–ZrO_(2)catalyst achieving high turnover frequency(TOF)of 10,627.3 mol_(H_(2))·mol_(Pt)^(−1)·h^(−1)and benzene selectivity of 99%at 295°C.The catalyst also demonstrates H_(2)evolution rate of 908 mmol·g_(Pt)^(−1)·min^(−1)and low deactivation rate of 0.0043 h^(−1).Remarkably,the catalyst displays outstanding stability and regeneration performance,maintaining its activity without significant loss during a 60-h dehydrogenation reaction and retaining a cyclohexane conversion of 77.2%after 10 consecutive cycles.Comprehensive characterization techniques,including XPS,CO-FTIR,NH_(3)-TPD,H_(2)-TPD,Benzene-TPD,and Py-IR,reveals that boron modification reduces the electron density of Pt,generating abundant electron-deficient Pt atoms.These electron-deficient Pt atoms enhance H_(2)adsorption and accelerate benzene desorption,effectively preventing coke formation from deep benzene dehydrogenation,which is responsible for the high catalytic performance of the Pt/0.5B–ZrO_(2)catalyst.These findings offer a valuable strategy for optimizing dehydrogenation catalysts in LOHC technologies,addressing a critical bottleneck in the development of this essential energy storage solution.展开更多
Rational design of catalytic sites to activate the C≡C bond is of paramount importance to advance acetylene hydrochlorination. Herein, Cu sites with electron-rich and electron-deficient states were constructed by con...Rational design of catalytic sites to activate the C≡C bond is of paramount importance to advance acetylene hydrochlorination. Herein, Cu sites with electron-rich and electron-deficient states were constructed by controlling the impregnation solutions. The π electrons flowing from acetylene to Cu site are facilitated over the electron-deficient Cu sites, achieving high activation of C≡C bond. The contradiction between the increased activation of acetylene required for enhanced catalytic activity and the resistance of Cu site to reduction by acetylene required for maintaining catalytic stability can be balanced by establishing strong interactions of Cu site with pyrrolic-N species. The catalytic activity displays a volcano shape scaling relationship as a function of Cu particle size. Tribasic copper chloride is concomitantly generated with the construction of electron-deficient Cu sites. The H–Cl bond of HCl can be activated over the tribasic copper chloride, accelerating the surface reaction of vinyl chloride production. This strategy of inducing electron deficiency provides new insight into the rational design of catalysts for the synthesis of vinyl chloride with a high catalytic performance.展开更多
An effective method for the synthesis of vinyl thioethers through the conjugate addition of ethanethiol to electron-deficient alkynes promoted by BF3.Et20 has been developed. Electron-deficient internal alkynes react ...An effective method for the synthesis of vinyl thioethers through the conjugate addition of ethanethiol to electron-deficient alkynes promoted by BF3.Et20 has been developed. Electron-deficient internal alkynes react with ethanethiol in this system to yield mainly Z-isomer of vinyl thioether adducts, while electron-deficient terminal alkynes afford mainly E-isomer of vinyl thioether adducts.展开更多
Copolymerization of an electron-rich donor(D)unit with an electron-deficient acceptor(A)unit to construct efficient D-π-A-πtype donors is an effective strategy for organic solar cell applications.The electron-defici...Copolymerization of an electron-rich donor(D)unit with an electron-deficient acceptor(A)unit to construct efficient D-π-A-πtype donors is an effective strategy for organic solar cell applications.The electron-deficient unit fusion,endows extendedπ-conjugation plane and insures excellent photoelectronic property,has great advantages to build A moiety and gradually receives considerable attention.In this work,we adopt benzo[2,1-b:3,4-b’]dithiophene and benzopyrazine(BP),benzothiadiazole(BT)and benzoselenadiazole(BS)to cleverly construct a series of fused A units with different electrondeficient ability,and further synthesize three polymer donors PBDP-BP,PBDP-BT,and PBDP-BS,respectively.The relationships between structure and performance were systematically investigated.PBDPBT shows a moderate aggregation behavior in both solution and film,and the highest hole mobility among the three polymers.After blending with Y6,the PBDP-BT:Y6-based film has the strongest absorption,favorable compatibility,superior crystallinity,and uniform phase separation morphology compared with PBDP-BP or PBDP-BS based blend films.Thus,the device based on PBDP-BT:Y6 has the highest and balanced charge mobility,suppressive recombination,reduced energy loss and achieves an outstanding PCE of 15.14%,which is superior to PBDP-BP:Y6(8.55%)and PBDP-BS:Y6(6.85%).These results provide learnable guidelines for future fused electron-deficient unit-based donor design for photovoltaic application.展开更多
An electron-deficient[CpERhCl2]2 catalyzed annulation of N-pentafluorophenylbenzamides with internal alkynes was successfully established under mild reaction conditions,with the assistance of Lewis acid silver salt.Pa...An electron-deficient[CpERhCl2]2 catalyzed annulation of N-pentafluorophenylbenzamides with internal alkynes was successfully established under mild reaction conditions,with the assistance of Lewis acid silver salt.Particularly,electron-deficient benzamide substrates were smoothly transformed into the desired products in this catalytic system.The catalytic system showed a broad tolerance for different substituents on the aromatic rings or aryl,alkyl-substituted alkynes.展开更多
The three-component reaction of triphenylphosphine,dimethyl hex-2-en-4-ynedioate and arylidene N,N’-dimethylbarbituric acids in dry methylene dichloride at room temperature afforded trans-1,3-disubstituted 7,9-diazas...The three-component reaction of triphenylphosphine,dimethyl hex-2-en-4-ynedioate and arylidene N,N’-dimethylbarbituric acids in dry methylene dichloride at room temperature afforded trans-1,3-disubstituted 7,9-diazaspiro[4.5]dec-1-enes in good yields and with high diastereoselectivity.However,the similar three-component reaction with arylidene Meldrum acids resulted in a mixtures of cis/trans-1,2-disubstituted 7,9-dioxaspiro[4.5]dec-1-enes.Additionally,the three-component reaction of triphenylphosphine,dimethyl but-2-ynedioate and arylidene Meldrum acids gave polysubstituted 5-(triphe nyl-λ~5-phosphanylidene)cyclopenta-1,3-die nes.A plausible reaction mechanism was proposed for the formation of various products with different regioselectivity and diastereoselectivity.展开更多
Organic photovoltaics and field-effect transistors have attracted considerable attention due to the easy fabrication,low cost,light weight,and flexibility.Unsymmetrical conjugated building blocks are widely utilized f...Organic photovoltaics and field-effect transistors have attracted considerable attention due to the easy fabrication,low cost,light weight,and flexibility.Unsymmetrical conjugated building blocks are widely utilized for the design of new organic π-functional materials in order to achieve high-performance electronic devices,which has become a hot research topic in recent years.In this review,we summarized some typical organic π-functional materials with regioregular conjugated backbones with unsymmetrical electron-deficiency moieties and focused on the influence of regiochemistry on the final device performance.展开更多
The method to fluorinate the terminal group has achieved remarkable success and been widely used to fine-tune the intrinsic properties of organic acceptor materials.Referring to chlorination,however,it gets less atten...The method to fluorinate the terminal group has achieved remarkable success and been widely used to fine-tune the intrinsic properties of organic acceptor materials.Referring to chlorination,however,it gets less attention and remains ambiguous effect on organic photovoltaic(OPV)cells.Herein,a new non-fullerene acceptor named Y19 was reported with benzotriazole as the electron-deficient core and 2Cl-ICs as the strong electron-withdrawing end groups.Y19 exhibits a wide film absorption band from 600 nm to 948 nm and low LUMO(the lowest unoccupied molecular orbital)energy level of−3.95 eV.Photovoltaic devices based on PM6:Y19 show high-power conversion efficiency(PCE)of 12.76%with high open-circuit voltage(Voc)of 0.84 V,short-circuit current density(Jsc)of 22.38 mA/cm2 and fill factor(FF)of 68.18%.Broad external quantum efficiency(EQE)response of over 60%in the range of 480−860 nm can be obtained.This study demonstrates that chlorination,as a low-cost molecular design strategy,has its own superiorities to improve device performance and promote the potential application in OPV.展开更多
Four new low-band-gap alternating copolymers （P-1, P-2, P-3 and P-4） based on electron-rich benzodithiophene and newly developed electron-deficient units, thienopyrazine or dithiadiazatrindene derivatives, were synt...Four new low-band-gap alternating copolymers （P-1, P-2, P-3 and P-4） based on electron-rich benzodithiophene and newly developed electron-deficient units, thienopyrazine or dithiadiazatrindene derivatives, were synthesized by Stille polycondensation. All polymers exhibit good solubility in common organic solvents and a broad absorption band in the visible to near-infrared regions. The film optical band gaps of the polymers are in the range of 1.28-2.07 eV and the highest occupied molecular orbital （HOMO） energy levels are in the range of-4.99 eV to -5.28 eV. Bulk heterojunction polymer solar cells （PSCs） of the polymers were fabricated with phenyl-C61-butyric acid methyl ester （PC61BM） as acceptor material, and a power conversion efficiency of 0.80% was realized with P-1 as donor material.展开更多
The BF_3OEt_2 catalyzed one-pot 1,3-dipolar cycloaddition reaction of benzylamines,isatins and dimethyl acetylenedicarboxylate in dry methylene dichloride afforded the functionalized dihydrospiro[indoline-3,2＇-pyrrol...The BF_3OEt_2 catalyzed one-pot 1,3-dipolar cycloaddition reaction of benzylamines,isatins and dimethyl acetylenedicarboxylate in dry methylene dichloride afforded the functionalized dihydrospiro[indoline-3,2＇-pyrroles]in moderate to good yields and with high diastereoselectivity.The reaction was accomplished by the tandem 1,3-dioplar cycloaddition of in situ generated azomethine ylide with acetylenedicarboxylate and the nucleophilic addition of pyrrole ring to second molecular acetylenedicarboxylate.展开更多
Electron-deficient viologens are widely used as ligands or structure-directing agents(SDAs)to synthesize crystalline X-ray induced photochromic materials.Here,a new rational strategy of anion-directed fold-ing a flexi...Electron-deficient viologens are widely used as ligands or structure-directing agents(SDAs)to synthesize crystalline X-ray induced photochromic materials.Here,a new rational strategy of anion-directed fold-ing a flexible cation(H_(2)imb)^(2+)((H_(2)imb)^(2+)=di-protonated 2,3-bis(imidazolin-2-yl)-2,3-dimethylbutane)has been developed.Electron-donating Cl−and(ZnCl4)2−are used to direct folding a flexible electron-deficient(H_(2)imb)^(2+)cation.Three complexes(H_(2)imb)(NO_(3))2(1),(H_(2)imb)Cl2·H_(2)O(2),and(H_(2)imb)ZnCl4(3)have been synthesized in which(H_(2)imb)^(2+)crystallize in an anti-conformation,88.8°-gauche,and 51.8°-gauche,respectively.In contrary to X-ray silent complex 1,X-ray induced photochromism has been achieved in both complex 2 and 3.An intermolecular charge-transfer mechanism has been elucidated and the anion directed folding of(H_(2)imb)^(2+)has been validated to be critical to yield colored long-lived charge-separated states.展开更多
The 1,3-dipolar cycloaddition reaction of dimethyl hex-2-en-4-ynedioate with azomethine ylides derived from reaction of L-proline with various isatins in methanol selectively resulted in the formation of functionalize...The 1,3-dipolar cycloaddition reaction of dimethyl hex-2-en-4-ynedioate with azomethine ylides derived from reaction of L-proline with various isatins in methanol selectively resulted in the formation of functionalized spiro[indoline-3,3’-pyrrolizine]acrylates as main products and spiro[indoline-3,3’-pyrrolizine]propiolates as minor products.This result indicated that the electron-deficient alkyne has higher reactivity than that of electron-deficient alkene in 1,3-dipolar cycloaddition reaction.展开更多
A simple method to synthesize luminescent λ^(5)-phosphanaphthalenes and zwitterionic nido-carborane fused six-membered phosphacycles was developed from the reaction of ortho-phosphinobenzoaldehydes or ortho-phosphino...A simple method to synthesize luminescent λ^(5)-phosphanaphthalenes and zwitterionic nido-carborane fused six-membered phosphacycles was developed from the reaction of ortho-phosphinobenzoaldehydes or ortho-phosphinocarboranylaldehydes with an electron-deficient alkyne,respectively.Similar results were obtained with the imino analogues.展开更多
A convenient synthetic protocol for the hexasubstituted benzene derivatives was successfully developed by DABCO promoted domino reaction of arylidene malononitrile with two molecules of dialkyl but-2-ynedioates.The do...A convenient synthetic protocol for the hexasubstituted benzene derivatives was successfully developed by DABCO promoted domino reaction of arylidene malononitrile with two molecules of dialkyl but-2-ynedioates.The domino reaction resulted in tetraalkyl 6-cyano-[1,1'-biphenyl]-2,3,4,5-tetracarboxylates in good to high yields.This formal[2+2+2]cycloaddition was believed to proceed with sequential nucleophilic addition.Michael addition,annulation and aromatization processes.展开更多
Organic solar cells(OSCs)are promising to access flexible,light weight and semi-transparent photovoltaic devices by low-cost solution fabrication.Recently,the fused-ring nonfullerene acceptors play an important role i...Organic solar cells(OSCs)are promising to access flexible,light weight and semi-transparent photovoltaic devices by low-cost solution fabrication.Recently,the fused-ring nonfullerene acceptors play an important role in promoting the research progress of the OSCs.The power conversion efficiencies(PCEs)have been rapidly boosted to over 14%in single junction OSCs with the development of new nonfullerene acceptors and the related devices[1-3].Although the PCEs of OSCs are still inferior to their inorganic counterparts,further improvement of the PCEs could be expected by the development of new photovoltaic materials.展开更多
Two novel fluorene-based copolymers (PFSD and PFMD) containing squaric acid or maleimide unit in the main chain were synthesized in good yields by Suzuki coupling reaction. The resulting polymers possess excellent the...Two novel fluorene-based copolymers (PFSD and PFMD) containing squaric acid or maleimide unit in the main chain were synthesized in good yields by Suzuki coupling reaction. The resulting polymers possess excellent thermal stability, high electron affinity and high photoluminescence (PL) quantum yields. They can fluoresce in yellow-light range due to either the charge transfer between a fluorene segment and an electron-deficient containing squaric acid/maleimide segment of the polymers or the Forster energy transfer between different polymer chains. The results from PL measurements of the isothermally heated polymer thin films show that the commonly observed aggregate excimer formation in polyfluorenes is very effectively suppressed in these two polymers due to the nonlinear structures of maleimide and squaric acid moieties. Double-layer polymer light-emitting diodes (PLED) were fabricated using the resulting polymers as the emitting layers and Ba or Mg : Ag (V : V= 10 : 1) as cathodes. All the devices show bright yellow emission (562-579 nm) with different maximum external quantum efficiencies (0.006%-1.13%). Compared with the other devices, indium-tin oxide (ITO)/polyethylenedioxythiophene (PEDOT) : polystyrene sulfonic acid (PSS)PFMD/Mg : Ag has the higher maximum external quantum efficiency of 1.13% at 564 cd/m2 with a bias of 8.4 V.展开更多
Rational design of catalytic sites to activate the inert N≡N bond is of paramount importance to advance N2 electroreduction. Here, guided by the theoretical predictions, we construct a NiFe layered double hydroxide (...Rational design of catalytic sites to activate the inert N≡N bond is of paramount importance to advance N2 electroreduction. Here, guided by the theoretical predictions, we construct a NiFe layered double hydroxide (NiFe-LDH) nanosheet catalyst with a high density of electron-deficient sites, which were achieved by introducing oxygen vacancies in NiFe-LDH. Density functional theory calculations indicate that the electron-deficient sites show a much lower energy barrier (0.76 eV) for the potential determining step compared with that of the pristine NiFe-LDH (2.02 eV). Benefiting from this, the NiFe-LDH with oxygen vacancies exhibits the greatly improved electrocatalytic activity, presenting a high NH3 yield rate of 19.44 µg·h−1·mgcat−1, Faradaic efficiency of 19.41% at −0.20 V vs. reversible hydrogen electrode (RHE) in 0.1 M KOH electrolyte, as well as the outstanding stability. The present work not only provides an active electrocatalyst toward N2 reduction but also offers a facile strategy to boost the N2 reduction.展开更多
Imide-based conjugated molecules have emerged as a highly promising class of building blocks for constructing n-type semiconducting materials with lowlying lowest unoccupied molecular orbitals and exceptional stabilit...Imide-based conjugated molecules have emerged as a highly promising class of building blocks for constructing n-type semiconducting materials with lowlying lowest unoccupied molecular orbitals and exceptional stability.Although imides,such as naphthalene diimides,perylene diimides and their lateral fused analogs,have been synthesized extensively,the design and synthesis of largerπ-extended molecules incorporating more than two imide groups are desirable but still very challenging.Herein,we report the synthesis of an unprecedented electron-deficient bisanthene tetraimide(ATI)containing a bisantheneconjugated core and four five-membered imide groups,which was successfully achieved via a combined approach of solution and on-surface synthesis.The chemical structures,electronic states,formation mechanism and aromaticity of ATI were systematically investigated by scanning tunneling microscopy,noncontact atomic force microscopy,scanning tunneling spectroscopy,and density functional theory calculations.展开更多
Fine-tuning of the electron-deficient unit in A-DA1D-A typed small-molecule acceptors (SMAs) plays a crucial role in developing efficient SMAs for organic solar cells (OSCs).Here,we developed a SMA based on benzo[4,5]...Fine-tuning of the electron-deficient unit in A-DA1D-A typed small-molecule acceptors (SMAs) plays a crucial role in developing efficient SMAs for organic solar cells (OSCs).Here,we developed a SMA based on benzo[4,5]thieno[2,3-b]quinoxaline,designated as QW1,as well as three SMAs based on 1-methylindoline-2,3-dione,identified as QW2,QW3,and QW4.Compared with QW2,QW1 displays slightly blue-shifted absorption spectra and a lower LUMO energy level due to the stronger electron-withdrawing capability of BTQx in contrast to MDO.On the other hand,the introduction of a bromine atom in QW3 and QW4 causes a blue shift in absorption and a reduction in the LUMO energy level compared to QW2.Density functional theory analysis reveals that QW1 exhibits the best molecular planarity,which endows QW1 with larger electron mobility and tighter molecular stacking.Consequently,PM6:QW1 device affords a better efficiency of 15.63% than those of the devices based on QW2 (14.25%),QW3 (13.21%) and QW4 (15.03%).Moreover,the QW4-based device yields the highest open-circuit voltage of 0.933 V,and the PM6:L8-BO:QW4 ternary device realizes a PCE of 19.03%.Overall,our work demonstrates that regulation of electron-deficient central units is an effective strategy to improve the photovoltaic performance of the resulting A-DA1D-A SMAs.展开更多
基金supported by National Research Foundation of Korea(NRF)(RS-2024-00336766 and RS-2023-00301974)support of the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(RS-2023-00220748)。
文摘Since 2009,perovskite solar cells(PSCs)have advanced significantly,achieving over 26%efficiency for single-junction devices and exceeding 34%for silicon-perovskite tandem cells.Despite these successes,the weak adhesion of C_(60)to perovskite layers,due to van der Waals interactions,hinders long-term stability.In this study,we introduce electron-deficient intermolecular adhesives(EDIAs)as a novel interlayer material to enhance adhesion between perovskite and C_(60)layers.Comprehensive analyses,including density functional theory calculations,microscopy,and spectroscopy,demonstrate that EDIAs,particularly NDI-C9-Ace comprising of three key functionalities:aπ-electron-deficient arene core,a hydrophobic passivation core,and a secondary-bond anchoring core,significantly improve bonding strength and recombination passivation.This leads to enhanced efficiency as well as enhanced mechanical and photochemical stability in PSCs.Long-term stability tests further confirm the superior durability of EDIA-enhanced devices.This study highlights EDIA as a promising strategy for enhancing the robustness and efficiency of PSCs.
基金supported by National Natural Science Foundation of China(22478076,U25B6005)National Key R&D Program of China(2021YFA1500302)+1 种基金Industrial Joint Fund of Qingyuan Innovation Laboratory(00422001)111 Project(D17005).
文摘The efficient storage and release of H_(2)are pivotal for the advancement of hydrogen energy technologies.Cyclohexane,as a promising liquid organic hydrogen carrier(LOHC),provides a safe and practical solution for H_(2)storage.However,the performance limitations of dehydrogenation catalysts have hindered the rapid development of LOHC technology.In this study,we successfully developed boron-modified Pt/ZrO_(2)catalysts,which exhibit exceptional catalytic performance in cyclohexane dehydrogenation.The optimal boron content is determined to be 0.5 wt.%,with the Pt/0.5B–ZrO_(2)catalyst achieving high turnover frequency(TOF)of 10,627.3 mol_(H_(2))·mol_(Pt)^(−1)·h^(−1)and benzene selectivity of 99%at 295°C.The catalyst also demonstrates H_(2)evolution rate of 908 mmol·g_(Pt)^(−1)·min^(−1)and low deactivation rate of 0.0043 h^(−1).Remarkably,the catalyst displays outstanding stability and regeneration performance,maintaining its activity without significant loss during a 60-h dehydrogenation reaction and retaining a cyclohexane conversion of 77.2%after 10 consecutive cycles.Comprehensive characterization techniques,including XPS,CO-FTIR,NH_(3)-TPD,H_(2)-TPD,Benzene-TPD,and Py-IR,reveals that boron modification reduces the electron density of Pt,generating abundant electron-deficient Pt atoms.These electron-deficient Pt atoms enhance H_(2)adsorption and accelerate benzene desorption,effectively preventing coke formation from deep benzene dehydrogenation,which is responsible for the high catalytic performance of the Pt/0.5B–ZrO_(2)catalyst.These findings offer a valuable strategy for optimizing dehydrogenation catalysts in LOHC technologies,addressing a critical bottleneck in the development of this essential energy storage solution.
基金Financial support from the National Natural Science Foundation of China (NSFCgrant No.U20A20119,21606199,22078302,52070035)+3 种基金the Science and Technology Department of Zhejiang Province (LGG20B060004)the China Postdoctoral Science Foundation (2020M671791)the Jilin Province Scientific and the Technological Planning Project of China (No.20200403001SF)the National Key Research and Development Program of China (2021YFA1501800,2021YFA1501801,2021YFA1501802)。
文摘Rational design of catalytic sites to activate the C≡C bond is of paramount importance to advance acetylene hydrochlorination. Herein, Cu sites with electron-rich and electron-deficient states were constructed by controlling the impregnation solutions. The π electrons flowing from acetylene to Cu site are facilitated over the electron-deficient Cu sites, achieving high activation of C≡C bond. The contradiction between the increased activation of acetylene required for enhanced catalytic activity and the resistance of Cu site to reduction by acetylene required for maintaining catalytic stability can be balanced by establishing strong interactions of Cu site with pyrrolic-N species. The catalytic activity displays a volcano shape scaling relationship as a function of Cu particle size. Tribasic copper chloride is concomitantly generated with the construction of electron-deficient Cu sites. The H–Cl bond of HCl can be activated over the tribasic copper chloride, accelerating the surface reaction of vinyl chloride production. This strategy of inducing electron deficiency provides new insight into the rational design of catalysts for the synthesis of vinyl chloride with a high catalytic performance.
基金the National Natural Science Foundation of China(No.21102179)Fundamental Research Funds for the Central Universities(No.JKZ2011011) for the financial support
文摘An effective method for the synthesis of vinyl thioethers through the conjugate addition of ethanethiol to electron-deficient alkynes promoted by BF3.Et20 has been developed. Electron-deficient internal alkynes react with ethanethiol in this system to yield mainly Z-isomer of vinyl thioether adducts, while electron-deficient terminal alkynes afford mainly E-isomer of vinyl thioether adducts.
基金financially supported by the National Natural Science Foundation of China(21733005,21975115 and 51903116)the Shenzhen Fundamental Research Program(JCYJ20200109140801751,JCYJ20190809163011543 and JCYJ20190809161413310)+2 种基金the Guangdong Provincial Key Laboratory of Catalysis(2020B121201002)the Guangdong Innovative and Entrepreneurial Research Team Program(2016ZT06G587)the Shenzhen Sci-Tech Fund(KYTDPT 20181011104007)。
文摘Copolymerization of an electron-rich donor(D)unit with an electron-deficient acceptor(A)unit to construct efficient D-π-A-πtype donors is an effective strategy for organic solar cell applications.The electron-deficient unit fusion,endows extendedπ-conjugation plane and insures excellent photoelectronic property,has great advantages to build A moiety and gradually receives considerable attention.In this work,we adopt benzo[2,1-b:3,4-b’]dithiophene and benzopyrazine(BP),benzothiadiazole(BT)and benzoselenadiazole(BS)to cleverly construct a series of fused A units with different electrondeficient ability,and further synthesize three polymer donors PBDP-BP,PBDP-BT,and PBDP-BS,respectively.The relationships between structure and performance were systematically investigated.PBDPBT shows a moderate aggregation behavior in both solution and film,and the highest hole mobility among the three polymers.After blending with Y6,the PBDP-BT:Y6-based film has the strongest absorption,favorable compatibility,superior crystallinity,and uniform phase separation morphology compared with PBDP-BP or PBDP-BS based blend films.Thus,the device based on PBDP-BT:Y6 has the highest and balanced charge mobility,suppressive recombination,reduced energy loss and achieves an outstanding PCE of 15.14%,which is superior to PBDP-BP:Y6(8.55%)and PBDP-BS:Y6(6.85%).These results provide learnable guidelines for future fused electron-deficient unit-based donor design for photovoltaic application.
基金We gratefully acknowledge the National Natural Science Foundation of China(Nos.21671097 and 21573106)the Fundamental Research Funds for the Central Universities for financial support.
文摘An electron-deficient[CpERhCl2]2 catalyzed annulation of N-pentafluorophenylbenzamides with internal alkynes was successfully established under mild reaction conditions,with the assistance of Lewis acid silver salt.Particularly,electron-deficient benzamide substrates were smoothly transformed into the desired products in this catalytic system.The catalytic system showed a broad tolerance for different substituents on the aromatic rings or aryl,alkyl-substituted alkynes.
基金financially supported by the National Natural Science Foundation of China(No.21572196)the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘The three-component reaction of triphenylphosphine,dimethyl hex-2-en-4-ynedioate and arylidene N,N’-dimethylbarbituric acids in dry methylene dichloride at room temperature afforded trans-1,3-disubstituted 7,9-diazaspiro[4.5]dec-1-enes in good yields and with high diastereoselectivity.However,the similar three-component reaction with arylidene Meldrum acids resulted in a mixtures of cis/trans-1,2-disubstituted 7,9-dioxaspiro[4.5]dec-1-enes.Additionally,the three-component reaction of triphenylphosphine,dimethyl but-2-ynedioate and arylidene Meldrum acids gave polysubstituted 5-(triphe nyl-λ~5-phosphanylidene)cyclopenta-1,3-die nes.A plausible reaction mechanism was proposed for the formation of various products with different regioselectivity and diastereoselectivity.
基金the National Basic Research Program of China(973 Program,No.2014CB643502)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB12010200)the National Natural Science Foundation of China(No.91333113)for financial support
文摘Organic photovoltaics and field-effect transistors have attracted considerable attention due to the easy fabrication,low cost,light weight,and flexibility.Unsymmetrical conjugated building blocks are widely utilized for the design of new organic π-functional materials in order to achieve high-performance electronic devices,which has become a hot research topic in recent years.In this review,we summarized some typical organic π-functional materials with regioregular conjugated backbones with unsymmetrical electron-deficiency moieties and focused on the influence of regiochemistry on the final device performance.
基金Project(21875286)supported by the National Natural Science Foundation of China。
文摘The method to fluorinate the terminal group has achieved remarkable success and been widely used to fine-tune the intrinsic properties of organic acceptor materials.Referring to chlorination,however,it gets less attention and remains ambiguous effect on organic photovoltaic(OPV)cells.Herein,a new non-fullerene acceptor named Y19 was reported with benzotriazole as the electron-deficient core and 2Cl-ICs as the strong electron-withdrawing end groups.Y19 exhibits a wide film absorption band from 600 nm to 948 nm and low LUMO(the lowest unoccupied molecular orbital)energy level of−3.95 eV.Photovoltaic devices based on PM6:Y19 show high-power conversion efficiency(PCE)of 12.76%with high open-circuit voltage(Voc)of 0.84 V,short-circuit current density(Jsc)of 22.38 mA/cm2 and fill factor(FF)of 68.18%.Broad external quantum efficiency(EQE)response of over 60%in the range of 480−860 nm can be obtained.This study demonstrates that chlorination,as a low-cost molecular design strategy,has its own superiorities to improve device performance and promote the potential application in OPV.
基金financially supported by the Russian Foundation for Basic Research(GFEN_a No.12-03-91175)the National Natural Science Foundation of China(No.51211120187)
文摘Four new low-band-gap alternating copolymers （P-1, P-2, P-3 and P-4） based on electron-rich benzodithiophene and newly developed electron-deficient units, thienopyrazine or dithiadiazatrindene derivatives, were synthesized by Stille polycondensation. All polymers exhibit good solubility in common organic solvents and a broad absorption band in the visible to near-infrared regions. The film optical band gaps of the polymers are in the range of 1.28-2.07 eV and the highest occupied molecular orbital （HOMO） energy levels are in the range of-4.99 eV to -5.28 eV. Bulk heterojunction polymer solar cells （PSCs） of the polymers were fabricated with phenyl-C61-butyric acid methyl ester （PC61BM） as acceptor material, and a power conversion efficiency of 0.80% was realized with P-1 as donor material.
基金financially supported by the National Natural Science Foundation of China (Nos. 21172189, 21572196)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The BF_3OEt_2 catalyzed one-pot 1,3-dipolar cycloaddition reaction of benzylamines,isatins and dimethyl acetylenedicarboxylate in dry methylene dichloride afforded the functionalized dihydrospiro[indoline-3,2＇-pyrroles]in moderate to good yields and with high diastereoselectivity.The reaction was accomplished by the tandem 1,3-dioplar cycloaddition of in situ generated azomethine ylide with acetylenedicarboxylate and the nucleophilic addition of pyrrole ring to second molecular acetylenedicarboxylate.
基金supported by National Natural Science Foundation of China(No.92261109)Natural Science Foundation of Fujian Province(No.2020J05080)+3 种基金Project Funded by China Postdoctoral Science Foundation(No.2023M733496)Natural Science Foundation of Xiamen(No.3502Z20206080)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZR110)Recruitment Program of Global Youth Experts,Youth Innovation Promotion Association CAS(No.2021302).
文摘Electron-deficient viologens are widely used as ligands or structure-directing agents(SDAs)to synthesize crystalline X-ray induced photochromic materials.Here,a new rational strategy of anion-directed fold-ing a flexible cation(H_(2)imb)^(2+)((H_(2)imb)^(2+)=di-protonated 2,3-bis(imidazolin-2-yl)-2,3-dimethylbutane)has been developed.Electron-donating Cl−and(ZnCl4)2−are used to direct folding a flexible electron-deficient(H_(2)imb)^(2+)cation.Three complexes(H_(2)imb)(NO_(3))2(1),(H_(2)imb)Cl2·H_(2)O(2),and(H_(2)imb)ZnCl4(3)have been synthesized in which(H_(2)imb)^(2+)crystallize in an anti-conformation,88.8°-gauche,and 51.8°-gauche,respectively.In contrary to X-ray silent complex 1,X-ray induced photochromism has been achieved in both complex 2 and 3.An intermolecular charge-transfer mechanism has been elucidated and the anion directed folding of(H_(2)imb)^(2+)has been validated to be critical to yield colored long-lived charge-separated states.
基金financially supported by the National Natural Science Foundation of China(No.21572196)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China。
文摘The 1,3-dipolar cycloaddition reaction of dimethyl hex-2-en-4-ynedioate with azomethine ylides derived from reaction of L-proline with various isatins in methanol selectively resulted in the formation of functionalized spiro[indoline-3,3’-pyrrolizine]acrylates as main products and spiro[indoline-3,3’-pyrrolizine]propiolates as minor products.This result indicated that the electron-deficient alkyne has higher reactivity than that of electron-deficient alkene in 1,3-dipolar cycloaddition reaction.
基金the National Natural Science Foundation of China(Nos.21672193,21272218)Ministry of Industry and Information Technology of the People's Republic of China(No.Z135060009002)+1 种基金111 Project(No.D20003)Zhengzhou University of China for financial support of this research。
文摘A simple method to synthesize luminescent λ^(5)-phosphanaphthalenes and zwitterionic nido-carborane fused six-membered phosphacycles was developed from the reaction of ortho-phosphinobenzoaldehydes or ortho-phosphinocarboranylaldehydes with an electron-deficient alkyne,respectively.Similar results were obtained with the imino analogues.
基金This work was financially supported by the National Natural Science Foundation of China(No.21572196)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘A convenient synthetic protocol for the hexasubstituted benzene derivatives was successfully developed by DABCO promoted domino reaction of arylidene malononitrile with two molecules of dialkyl but-2-ynedioates.The domino reaction resulted in tetraalkyl 6-cyano-[1,1'-biphenyl]-2,3,4,5-tetracarboxylates in good to high yields.This formal[2+2+2]cycloaddition was believed to proceed with sequential nucleophilic addition.Michael addition,annulation and aromatization processes.
文摘Organic solar cells(OSCs)are promising to access flexible,light weight and semi-transparent photovoltaic devices by low-cost solution fabrication.Recently,the fused-ring nonfullerene acceptors play an important role in promoting the research progress of the OSCs.The power conversion efficiencies(PCEs)have been rapidly boosted to over 14%in single junction OSCs with the development of new nonfullerene acceptors and the related devices[1-3].Although the PCEs of OSCs are still inferior to their inorganic counterparts,further improvement of the PCEs could be expected by the development of new photovoltaic materials.
基金Project supported by the National Natural Science Foundation of China (No. 20102004).
文摘Two novel fluorene-based copolymers (PFSD and PFMD) containing squaric acid or maleimide unit in the main chain were synthesized in good yields by Suzuki coupling reaction. The resulting polymers possess excellent thermal stability, high electron affinity and high photoluminescence (PL) quantum yields. They can fluoresce in yellow-light range due to either the charge transfer between a fluorene segment and an electron-deficient containing squaric acid/maleimide segment of the polymers or the Forster energy transfer between different polymer chains. The results from PL measurements of the isothermally heated polymer thin films show that the commonly observed aggregate excimer formation in polyfluorenes is very effectively suppressed in these two polymers due to the nonlinear structures of maleimide and squaric acid moieties. Double-layer polymer light-emitting diodes (PLED) were fabricated using the resulting polymers as the emitting layers and Ba or Mg : Ag (V : V= 10 : 1) as cathodes. All the devices show bright yellow emission (562-579 nm) with different maximum external quantum efficiencies (0.006%-1.13%). Compared with the other devices, indium-tin oxide (ITO)/polyethylenedioxythiophene (PEDOT) : polystyrene sulfonic acid (PSS)PFMD/Mg : Ag has the higher maximum external quantum efficiency of 1.13% at 564 cd/m2 with a bias of 8.4 V.
基金This work was supported by the National Natural Science Foundation of China (No. 21603208)Shenzhen Science and Technology Project (Nos. JCYJ20170412105400428 and JCYJ20180507182246321)+3 种基金Shenzhen Peacock Technological Innovation Project (No. KQJSCX20170727101208249)Fundamental Research Funds for the Central Universities, the Open Project Program of the State Key Laboratory of Silicon Materials, Zhejiang University, and China Postdoctoral Science Foundation (No. 2019M663058)This research was undertaken with the assistance of resources provided by the National Computational Infrastructure (NCI) facility at the Australian National Universityallocated through both the National Computational Merit Allocation Scheme supported by the Australian Government and the Australian Research Council grant LE190100021 (Sustaining and strengthening merit-based access at NCI, 2019–2021).
文摘Rational design of catalytic sites to activate the inert N≡N bond is of paramount importance to advance N2 electroreduction. Here, guided by the theoretical predictions, we construct a NiFe layered double hydroxide (NiFe-LDH) nanosheet catalyst with a high density of electron-deficient sites, which were achieved by introducing oxygen vacancies in NiFe-LDH. Density functional theory calculations indicate that the electron-deficient sites show a much lower energy barrier (0.76 eV) for the potential determining step compared with that of the pristine NiFe-LDH (2.02 eV). Benefiting from this, the NiFe-LDH with oxygen vacancies exhibits the greatly improved electrocatalytic activity, presenting a high NH3 yield rate of 19.44 µg·h−1·mgcat−1, Faradaic efficiency of 19.41% at −0.20 V vs. reversible hydrogen electrode (RHE) in 0.1 M KOH electrolyte, as well as the outstanding stability. The present work not only provides an active electrocatalyst toward N2 reduction but also offers a facile strategy to boost the N2 reduction.
基金support from the National Natural Science Foundation of China(grant nos.22161132026,21790053,51821002,and 21602225)the Suzhou Key Laboratory of Surface and Interface Intelligent Matter(grant no.SZS2022011)+2 种基金the Collaborative Innovation Center of Suzhou Nano Science and Technologythe Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the 111 project.
文摘Imide-based conjugated molecules have emerged as a highly promising class of building blocks for constructing n-type semiconducting materials with lowlying lowest unoccupied molecular orbitals and exceptional stability.Although imides,such as naphthalene diimides,perylene diimides and their lateral fused analogs,have been synthesized extensively,the design and synthesis of largerπ-extended molecules incorporating more than two imide groups are desirable but still very challenging.Herein,we report the synthesis of an unprecedented electron-deficient bisanthene tetraimide(ATI)containing a bisantheneconjugated core and four five-membered imide groups,which was successfully achieved via a combined approach of solution and on-surface synthesis.The chemical structures,electronic states,formation mechanism and aromaticity of ATI were systematically investigated by scanning tunneling microscopy,noncontact atomic force microscopy,scanning tunneling spectroscopy,and density functional theory calculations.
基金supported by the Shenzhen Science and Technology Program(ZDSYS20210623091813040,RCBS20221008093225021)the National Natural Science Foundation of China(NSFC,No.22309119)+2 种基金G.Li acknowledges the support from Research Grants Council of Hong Kong(Project Nos.15320216,15221320,C5037-18G,RGC Senior Research Fellowship Scheme(SRFS2223-5S01))the Hong Kong Polytechnic University(Sir Sze-yuen Chung Endowed Professorship Fund(8-8480)PolyU Distinguished postdoc Fellowship(1-YW4C,R.Ma),G-SAC5)。
文摘Fine-tuning of the electron-deficient unit in A-DA1D-A typed small-molecule acceptors (SMAs) plays a crucial role in developing efficient SMAs for organic solar cells (OSCs).Here,we developed a SMA based on benzo[4,5]thieno[2,3-b]quinoxaline,designated as QW1,as well as three SMAs based on 1-methylindoline-2,3-dione,identified as QW2,QW3,and QW4.Compared with QW2,QW1 displays slightly blue-shifted absorption spectra and a lower LUMO energy level due to the stronger electron-withdrawing capability of BTQx in contrast to MDO.On the other hand,the introduction of a bromine atom in QW3 and QW4 causes a blue shift in absorption and a reduction in the LUMO energy level compared to QW2.Density functional theory analysis reveals that QW1 exhibits the best molecular planarity,which endows QW1 with larger electron mobility and tighter molecular stacking.Consequently,PM6:QW1 device affords a better efficiency of 15.63% than those of the devices based on QW2 (14.25%),QW3 (13.21%) and QW4 (15.03%).Moreover,the QW4-based device yields the highest open-circuit voltage of 0.933 V,and the PM6:L8-BO:QW4 ternary device realizes a PCE of 19.03%.Overall,our work demonstrates that regulation of electron-deficient central units is an effective strategy to improve the photovoltaic performance of the resulting A-DA1D-A SMAs.
