Fluorinated fused azobenzene boron(FBAz)is a novel electron-deficient building block for polymer electron acceptors in all-polymer solar cells(all-PSC).The B←N bridging units impart a fixed configuration and low-lyin...Fluorinated fused azobenzene boron(FBAz)is a novel electron-deficient building block for polymer electron acceptors in all-polymer solar cells(all-PSC).The B←N bridging units impart a fixed configuration and low-lying LUMO/HOMO energy.Three polymer acceptor materials(P2f,P3f and P5f)with different fluorine substitution positions by copolymerizing FBAz with indacenodithiophene(IDT),are synthesized and investigated to study the influence of fluorinated forms on the all-polymer solar cell performance.The FBAz units are synthesized in just three steps,facilitating the straightforward production of polymer acceptors P2f,P3f,and P5f.These acceptors exhibit strong light absorption in the visible to near-infrared range of 500-1000nm and possess suitable LUMO/HOMO energy levels of-3.99/-5.66 eV which are very complementary to that(E_(LUMO/HOMO)=-3.59/-5.20 eV)of the widely-used polymer donor poly[(ethylhexylthiophenyl)-benzodithiophene-(ethylhexyl)-thienothiophene](PTB7-Th).All-polymer solar cells(all-PSCs)with PTB7-Th as electron donor and P3f as electron acceptor exhibits highest power conversion efficiencies(PCE)2.70%.When PC_(61)BM is added as the third component,the device efficiency can reach 5.36%.These preliminary results indicate that FBAz is a promising strong electron acceptor for the development of n-type polymer semiconductors,especially in organic photovoltaics(OPVs).To the best of our knowledge,this is the first example demonstrating the unique photovoltaic properties of the N=N double bond as an acceptor material.展开更多
Integrating high-nickel layered oxide cathodes with aqueous slurry electrode preparation routes holds the potential to simultaneously meet the demands for high energy density and low-cost production of lithium-ion bat...Integrating high-nickel layered oxide cathodes with aqueous slurry electrode preparation routes holds the potential to simultaneously meet the demands for high energy density and low-cost production of lithium-ion batteries.However,the influence of dual exposure to air and liquid water as well as the heating treatment during aqueous slurry electrode processing on the high-nickel layered oxide electrode is yet to be understood.In this study,we systematically investigate the structural evolution and electro-chemical behaviors when LiNi_(0.83)Mn_(0.05)Co_(0.12)O_(2)(NMC83)is subjected to aqueous slurry processing.It was observed that the crystal structure near the surface of NMC83 is partially reconstructed to contain a mixture of rock-salt and layered phases when exposed to water,leading to the deteriorated rate capability of the NMC83 electrodes.This partial surface reconstruction layer completely converts into a pure rock-salt phase upon cycling,accompanied by the release of O_(2),Ni leaching,catalyzed decomposition of the electrolyte,and the formation of a thick cathode electrolyte interphase layer.The byproducts of the electrolyte and dissolved Ni could shuttle to the Li metal side,causing a crosstalk effect that results in a thick and unstable solid electrolyte interphase layer on the Li surface.These in combination severely undermined the cycling stability of the NMC83 electrodes obtained from the aqueous slurry.A mitigation strategy using molecular self-assembly technique was demonstrated to enhance the surface stability of water-treated NMC83.Our findings offer new insights for tailoring ambient environment stability and aqueous slurry processability for ultra-high nickel layered oxide and other water-sensitive cathode materials.展开更多
Periodontitis is an inflammatory disease caused by oxidative stress and initiated by bacterial infection.The endogenous enzyme system is dysfunctional in the periodontitis microenvironment.Currently,traditional clinic...Periodontitis is an inflammatory disease caused by oxidative stress and initiated by bacterial infection.The endogenous enzyme system is dysfunctional in the periodontitis microenvironment.Currently,traditional clinical treatment cannot efficiently eliminate bacteria or relieve inflammation.To address this issue,we developed ultrasmall ruthenium nanoparticles(US-RuNPs)with multienzyme-like activity.Our results indicated that US-RuNPs with an amplified electric field had a superior photothermal effect to large-sized RuNPs.Thus,US-RuNPs,through photothermal therapy(PTT),acted as“bacterial lysozyme”to eliminate planktonic pathogens and biofilms.In addition,the antioxidant enzyme-like activity of US-RuNPs was greater than that of large-sized RuNPs,and US-RuNPs could scavenge intracellular reactive oxygen species(ROS)and inhibit inflammation-related responses.More importantly,US-RuNPs demonstrated a satisfactory effect against periodontitis in vivo due to their synergistic antibacterial activity through PTT and antioxidant effects even in deep sites,decreasing the alveolar bone loss to root length ratio(ABL/RL)from 70.70%to 20.15%and increasing the collagen volume fraction from 16.88%to 57.64%.Thus,US-RuNPs with approximately 2 nm diameter,mimicking multienzyme activity,have great potential for the treatment of periodontitis.展开更多
Herein,we fabricate an embedding structure at the interface between Pt nanoparticles(NPs)and CeO_(2)-{100}nanocubes with surface defect sites(CeO_(2)-SDS)through quenching and gas bubbling-assisted membrane reduction ...Herein,we fabricate an embedding structure at the interface between Pt nanoparticles(NPs)and CeO_(2)-{100}nanocubes with surface defect sites(CeO_(2)-SDS)through quenching and gas bubbling-assisted membrane reduction methods.The in-situ substitution of Pt NPs for atomic-layer Ce lattice significantly increases the amount of reactive oxygen species from 133.68μmol/g to 199.44μmol/g.As a result,the distinctive geometric structure of Pt/CeO_(2)-SDS catalyst substantially improves the catalytic activity and stability for soot oxidation compared with the catalyst with no quenching process,i.e.,its T_(50)and TOF values are 332°C and 2.915 h^(-1),respectively.Combined with the results of experimental investigations and density functional theory calculations,it is unveiled that the unique embedding structure of Pt/CeO_(2)-SDS catalyst can facilitate significantly electron transfer from Pt to the CeO_(2)-{100}support,and induce the formation of interfacial[Ce-O_(x)-Pt_(2)]bond chains,which plays a crucial role in enhancing the key step of soot oxidation through the dual activation of surface lattice oxygen and molecular O_(2).Such a fundamental revelation of the interfacial electronic transmission and corresponding modification strategy contributes a novel opportunity to develop high-efficient and stable noble metal catalysts at the atomic level.展开更多
RNA offers distinct advantages for molecular self-assembly as a unique and programmable biomaterial.Recently,single-stranded RNA(ssRNA)origamis,capable of self-folding into defined nanostructures within a single-stran...RNA offers distinct advantages for molecular self-assembly as a unique and programmable biomaterial.Recently,single-stranded RNA(ssRNA)origamis,capable of self-folding into defined nanostructures within a single-stranded RNA molecule,are considered a promising platform for immune recognition and therapy.Here,we utilize single-stranded rod RNA origami(Rod RNA-OG)as functional nucleic acid to synthesize valence-programmed RNA structures in a one-pot manner.We discover that the polyvalent RNA origamis are resistant to RNase degradation and can be efficiently internalized by macrophages for subsequent innate immune activation,even in the absence of any external protective agents such as lipids or polymers.The valence-programmed RNA origamis thus hold great promise as novel agonists for immunotherapy.展开更多
Designing Fischer-Tropsch synthesis(FTS)catalysts to selectively produce liquid hydrocarbon fuels is a crucial challenge.Herein,we selectively introduced Co nanoparticles(NPs)into the micropores and mesopores of an or...Designing Fischer-Tropsch synthesis(FTS)catalysts to selectively produce liquid hydrocarbon fuels is a crucial challenge.Herein,we selectively introduced Co nanoparticles(NPs)into the micropores and mesopores of an ordered mesoporous MFI zeolite(OMMZ)through impregnation,which controlled the carbon number distribution in the FTS products by tuning the position of catalytic active sites in differently sized pores.The Co precursors coordinated by acetate with a size of 9.4×4.2×2.5Åand by 2,2'-bipyridine with a size of 9.5×8.7×7.9Å,smaller and larger than the micropores(ca.5.5Å)of MFI,made the Co species incorporated in OMMZ's micropores and mesopores,respectively.The carbon number products synthesized with the Co NPs confined in mesopores were larger than that in micropores.The high jet and diesel selectivities of 66.5%and 65.3%were achieved with Co NPs confined in micropores and mesopores of less acidic Na-type OMMZ,respectively.Gasoline and jet selectivities of 76.7%and 70.8%were achieved with Co NPs confined in micropores and mesopores of H-type OMMZ with Brönsted acid sites,respectively.A series of characterizations revealed that the selective production of diesel and jet fuels was due to the C-C cleavage suppressing of heavier hydrocarbons by the Co NPs located in mesopores.展开更多
Metal-backboned polymers with anisotropy microstructures are promising for conductive,optoelectronic,and magnetic functional materials.However,the structure-property relationships governing the interplay between the c...Metal-backboned polymers with anisotropy microstructures are promising for conductive,optoelectronic,and magnetic functional materials.However,the structure-property relationships governing the interplay between the chemical structure and electromagnetic property of the metal-backboned polymer have been rarely investigated.Here we report a carbon/nickel hybrid from metal-backboned polymer to serve as electromagnetic wave-absorbing materials,which exhibit high microwave absorption capacity and tunable absorption band.The presence of nickel backbones promote the generation of heterogeneous interfaces with carbon during calcination,thereby enhancing the wave-absorbing capacity of the carbon/nickel hybrid.The C/Ni hybrids show a minimal reflection loss of-49.1 dB at 13.04 GHz,and its frequency of the absorption band can be adjusted by controlling the thickness of the absorption layer.展开更多
Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy density.However,uneven Li deposition be...Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy density.However,uneven Li deposition behavior still occurs at the top of 3D frameworks owing to the local accumulation of Li ions.To promote uniform Li deposition without top dendrite growth,herein,a layered multifunctional framework based on oxidation-treated polyacrylonitrile(OPAN) and metal-organic framework(MOF) derivatives was proposed for rationally regulating the distribution of Li ions flux,nucleation sites,and electrical conductivity.Profiting from these merits,the OPAN/carbon nano fiber-MOF(CMOF) composite framework demonstrated a reversible Li plating/stripping behavior for 500 cycles with a stable Coulombic efficiency of around 99.0% at the current density of 2 mA/cm~2.Besides,such a Li composite anode exhibited a superior cycle lifespan of over 1300 h under a low polarized voltage of 18 mV in symmetrical cells.When the Li composite anode was paired with LiFePO_(4)(LFP) cathode,the obtained full cell exhibited a stable cycling over 500 cycles.Moreover,the COMSOL Multiphysics simulation was conducted to reveal the effects on homogeneous Li ions distribution derived from the above-mentioned OPAN/CMOF framework and electrical insulation/conduction design.These electrochemical and simulated results shed light on the difficulties of designing stable and safe Li metal anode via optimizing the 3D frameworks.展开更多
The lithium-sulfur reaction can contribute to the chemical electrical energy conversion capacity due to the multi-level ion/electron transfer process. However, the appearance of soluble intermediate products prevents ...The lithium-sulfur reaction can contribute to the chemical electrical energy conversion capacity due to the multi-level ion/electron transfer process. However, the appearance of soluble intermediate products prevents efficient electron transfer, making it impossible to achieve stable cycling and capacity contribution. Restricted catalysis provides a solution for inhibiting the shuttle of soluble lithium polysulfides.Herein, MXene aerogel with optimized channel utilization is designed as S host according to the polysulfide control strategy of localization, adsorption, and catalysis. With the help of the results of oriented channels, the polysulfide conversion process is optimized, providing a comprehensive scheme for inhibiting the shuttle effect. Lithium sulfur catalytic batteries have achieved high capacity and stable cycling.This system provides a comprehensive solution for lithium sulfur reaction catalysis and a new perspective for the functional application of MXene based lithium sulfur batteries.展开更多
Chiral carbonyl compounds frequently occur in natural products and pharmaceuticals. Additionally, they serve as important intermediates in organic synthesis. Transition metal-catalyzed asymmetric carbonylative cross-c...Chiral carbonyl compounds frequently occur in natural products and pharmaceuticals. Additionally, they serve as important intermediates in organic synthesis. Transition metal-catalyzed asymmetric carbonylative cross-coupling reactions are among the most straightforward and effective methods for synthesizing chiral carbonyl compounds, including esters, amides, and ketones. The advances in asymmetric carbonylative cross-coupling reactions using various O-, N-, C-, and S-containing nucleophiles or electrophiles over the past decade are summarized.展开更多
As one of the most essential components in photocuring system,photoinitiators(PIs)exert a crucial influence on the properties of the cured product.However,commercially available PIs encounter challenges in simultaneou...As one of the most essential components in photocuring system,photoinitiators(PIs)exert a crucial influence on the properties of the cured product.However,commercially available PIs encounter challenges in simultaneously achieving efficient photoinitiation performance and excellent light absorption properties,significantly limiting their applications in various fields.Here,two bis-chalcones and four corresponding oxime esters(OXEs)were designed and synthesized as highly efficient PIs.Featuring a structure comprising bis-chalcone and two diphenyl sulfides,the conjugated systems in these compounds enhance their light-absorption properties in near-ultraviolet and visible region,effectively.Both the frontier molecular orbital simulations and excited state calculations suggest the contribution of sulfur atoms to electron delocalization and the formation of conjugated structure.Due to the high reactivity of the N–O bond in OXE moiety,the four OXEs exhibit exceptional free radical photoinitiating ability in commercial acrylic monomers/oligomers with LED@365nm as light source.Notably,one of them demonstrates superior performance in the photoinitiation of multifunctional crosslinker,achieving more than 70%conversion within 3 s,coupled with outstanding absorption at 365 nm.These chalcone-based OXEs are considered to exert significant potential in the realm of free radical photocuring.展开更多
Control crosslink network and chain connectivity are essential to develop shape memory polymers(SMPs)with high shape memory capabilities,adjustable response temperature,and satisfying mechanistical properties.In this ...Control crosslink network and chain connectivity are essential to develop shape memory polymers(SMPs)with high shape memory capabilities,adjustable response temperature,and satisfying mechanistical properties.In this study,novel poly(ε-caprolactone)(PCL)-poly(2-vinyl)ethylene glycol(PVEG)copolymers bearing multi-pendant vinyl groups is synthesized by branched-selective allylic etherification polymerization of vinylethylene carbonate(VEC)with linear and tetra-arm PCLs under a synergistic catalysis of palladium complex and boron reagent.Facile thiol-ene photo-click reaction of PCL-PVEG copolymers with multifunctional thiols can rapidly access a serious crosslinked SMPs with high shape memory performance.The thermal properties,mechanical properties and response temperature of the obtained SMPs are tunable by the variation of PCL prepolymers,vinyl contents and functionality of thiols.Moreover,high elastic modulus in the rubbery plateau region can be maintained effectively owing to high-density topological networks of the PCL materials.In addition,the utility of the present SMPs is further demonstrated by the post-functionalization via thiol-ene photo-click chemistry.展开更多
Incorporating a low density of ester units into the backbone of polyethylene materials enhances their sustainability and recyclability while maintaining the main material properties of polyethylenes.Here we report a n...Incorporating a low density of ester units into the backbone of polyethylene materials enhances their sustainability and recyclability while maintaining the main material properties of polyethylenes.Here we report a new way to access degradable polyethylene materials with a low content of in-chain ester units via mechanochemical backbone editing.Initially,ester groups are incorporated as side groups through catalytic copolymerization of ethylene with a cyclobutene-fused lactone monomer(CBL),yielding polyethylene materials with high molecular weights and adjustable thermomechanical properties.Subsequent solid-state ball-milling treatment selectively introduces side-chain ester groups into the main chain of the polyethylene materials via force-induced cycloreversion of the cyclobutane units.Under acidic conditions,hydrolysis of the resultant polyethylene materials with in-chain ester units facilitates further degradation into oligomers.展开更多
Using natural resources to construct electrocatalysts for biomass conversion and elucidating their catalytic mechanisms are of great significance,but have remained challenging.Here,a series of two-dimensional(2D)bioma...Using natural resources to construct electrocatalysts for biomass conversion and elucidating their catalytic mechanisms are of great significance,but have remained challenging.Here,a series of two-dimensional(2D)biomass-based Pb/PbO@C nanoparticles catalysts with Pb/PbO anchored on carbon nanosheets were synthesized using natural-derived humate as the precursor.By adjusting the carbonization temperature,an electron-deficient Pb0/Pb^(2+)dual-center-site catalyst can be achieved.The optimized Pb/PbO@C catalyst showed an excellent performance for the electrochemical hydrogenation of 5 hydroxymethylfurfural(HMF)to high value-added 2,5 bis(hydroxymethyl)furan(BHMF),with high Faradaic efficiency(FE:91.9%)and selectivity(Sel:89.7%),achieving comparable performance to those of the reported noble metal-based electrocatalysts.Mechanism study revealed that the electron-deficient Pb^(0)/Pb^(2+)dual-center-site provided abundant Lewis acidic sites and promoted the dissociation of water to the active hydrogen(H^(*))species,thus enhancing the adsorption of HMF on Pb^(2+)sites and the coverage of H^(*)species on Pb0 sites.The high coverage of H*species and the synergistic effect of dual-center sites substantially promoted the binding of H*and HMF to form H-HMF^(*)and inhibited the recombination of H^(*)species,thereby accelerating the reaction kinetics of HMF reduction.展开更多
The bicarbonate-formate(HCO_(3)−–HCO_(2)−)interconversion provides a promising cycle for a conveniently accessible hydrogen storage system via reversible dehydrogenation and hydrogenation processes.Existing catalytic...The bicarbonate-formate(HCO_(3)−–HCO_(2)−)interconversion provides a promising cycle for a conveniently accessible hydrogen storage system via reversible dehydrogenation and hydrogenation processes.Existing catalytic systems often use organic solvents,tedious optimization as well as manipulation of pH values,solvent,pressure and various additives.Herein,we present an operational,robust,safe and cost-effective catalytic system for hydrogen storage and liberation.We have established a unique catalytic system with two different solid organometallic assemblies(NHC-Ru and NHC-Ir)that facilitate the reversible transformation between sodium formate and bicarbonate in aqueous solutions collaboratively and efficiently.Notably,the NHC-Ru catalyst is privileged for the hydrogenation of sodium bicarbonate,whereas the NHC-Ir component enables the dehydrogenation of sodium formate,all in a single reaction vessel.What sets this system apart is its simplicity.The H_(2)discharging and recharging is simply regulated by heating the mixture with or without H_(2).Remarkably,this process requires no extra additives or supplementary treatments.Moreover,the reversible hydrogen storage system is durable and can be reused for over 30 cycles without a discernible decline in activity and selectivity.The strategic paradigm in this study shows significant practical potential in hydrogen fuel cell applications.展开更多
Solid-state electrolytes are considered to be the vital part of the next-generation solid-state batteries(SSBs),due to their high safety and long operation life span.However,the two major factors that impede the expec...Solid-state electrolytes are considered to be the vital part of the next-generation solid-state batteries(SSBs),due to their high safety and long operation life span.However,the two major factors that impede the expected performance of batteries are:the easy formation of lithium dendrites due to the concentration gradient of anions,and the low ionic conductivity at room temperature,which prevents reaching ideal electrochemical performance.Single-ion quasi-solid-state electrolytes(SIQSSEs)could provide higher safety and energy density,owing to absence of anion concentration gradient and solvent,as well as good lithium-ion transport ability.The porous covalent organic frameworks(COFs)are beneficial for con-structing appropriate lithium-ion transport pathway,due to the ordered 1D channel.In addition,the boroxine COFs(COF-5)offers strong ability of withdrawing anion part of lithium salt.Last but not the least,boron atom could play the role of coordinate site due to its electron deficiency.These advantages afford an opportunity to obtain a SIQSSE with high ionic conductivity and high lithium transference number(LTN)simultaneously.The COF-5 based SIQSSEs delivered a high ionic conductivity of 6.3×10^(-4)S·cm^(-1),with a high LTN of 0.92 and a wide electrochemical stable window(ESW)of 4.7 V at room temperature.The LiFePO4(LFP)/Li cells,which was assembled with COF-5 based SIQSSE,exhibited outstanding long cycle stability,high initial capacity and favorable rate performance.The results indicated COFs could be an ideal material for single-ion solid-state electrolytes in next-generation batteries.展开更多
Immunization has long played essential roles in preventing diseases.However,the desire for precision delivery of vaccines to boost a robust immune response remains largely unmet.Here,we describe the use of acupoint de...Immunization has long played essential roles in preventing diseases.However,the desire for precision delivery of vaccines to boost a robust immune response remains largely unmet.Here,we describe the use of acupoint delivery of nanovaccines(ADN)to elicit dual-niche immunological priming.ADN can simultaneously stimulate mast cell-assisted maturation of dendritic cells at the acupoint and enable direct delivery of nanovaccines into the draining lymph nodes.We demonstrate that ADN not only provokes antigen presentation by lymph node-resident CD8α^(+)dendritic cells,but also induces the accumulation of nanovaccines in B-cell zones,amplifying antigen-specific cytotoxic T lymphocyte responses and immunoglobulin G antibody expression in draining lymph nodes.ADN also generates systemic immune responses by causing immune memory and preventing T-cell anergy in the spleen.Further supported by evoking effective antitumor responses and high-level antiviral antibodies in mice,ADN provides a simple yet versatile platform for advanced nanovaccination.展开更多
The structural change-mediated catalytic activity regulation plays a significant role in the biological functions of natural enzymes.However,there is virtually no artificial nanozyme reported that can achieve natural ...The structural change-mediated catalytic activity regulation plays a significant role in the biological functions of natural enzymes.However,there is virtually no artificial nanozyme reported that can achieve natural enzyme-like stringent spatiotemporal structure-based catalytic activity regulation.Here,we report a subnanostructural transformable gold@ceria(STGC-PEG)nanozyme that performs tunable catalytic activities via near-infrared(NIR)light-mediated sub-nanostructural transformation.The gold core in STGC-PEG can generate energetic hot electrons upon NIR irradiation,wherein an internal sub-nanostructural transformation is initiated by the conversion between CeO;and electron-rich state of CeO;-x,and active oxygen vacancies generation via the hot-electron injection.Interestingly,the sub-nanostructural transformation of STGC-PEG enhances peroxidase-like activity and unprecedentedly activates plasmon-promoted oxidase-like activity,allowing highly efficient low-power NIR light(50 m W cm;)-activated photocatalytic therapy of tumors.Our atomic-level design and fabrication provide a platform to precisely regulate the catalytic activities of nanozymes via a light-mediated sub-nanostructural transformation,approaching natural enzyme-like activity control in complex living systems.展开更多
Herein,we designed and constructed two metallacycles,1 and 2,to illustrate the conformational effect of isomeric AIE fluoropho res on the platfo rm of supramolecular coordination complexe s(SCCs).Specifically,the dang...Herein,we designed and constructed two metallacycles,1 and 2,to illustrate the conformational effect of isomeric AIE fluoropho res on the platfo rm of supramolecular coordination complexe s(SCCs).Specifically,the dangling phenyl rings in TPE units of the metallacycle 1 align completely outside the main cyclic structure,while in the metallacycle 2,these phenyl rings align half inside and half outside.The experimental results showed that two metallacycles exhibited different behaviors in terms of AIE fluorescence and chemical sensing,which could be attributed to the subtle structural difference of the TPE units.This work repre sents the unification of topics such as self-assembly,AIE,and chemical sensing,and further promotes the understanding for the structure-property relationship of isomeric AIE fluorophores.展开更多
The morphology manipulation of the active layers is important for improving the performance of organic photovoltaics(OPVs).The choice of processing solvent has great impact on the crystallization and phase separation ...The morphology manipulation of the active layers is important for improving the performance of organic photovoltaics(OPVs).The choice of processing solvent has great impact on the crystallization and phase separation during film formation,since solvent properties,including solvent effect on molecular crystallization,boiling point,and interaction parameters,can directly change the evolution pathways associated with thermodynamics and kinetics.Therefore,revealing the underlying solvent-regulated morphology mechanism is potential to provide guiding strategies for device optimization.In this study,chloroform,chlorobenzene,and toluene are used to process PM6:Y6 blends by slot-die printing to fabricate OPV devices.The chloroform printed film forms a fibrillar network morphology with enhanced crystallization,facilitating exciton dissociation,charge transport and extraction,resulting in an optimal power conversion efficiency of 16.22%.However,the addition of the additive chloronaphthalene in chloroform solution leads to over-crystallization of Y6,and thus,increasing domain size that exceeds the exciton diffusion length,resulting in lower device efficiency.In addition,both the chlorobenzene and toluene suppress the crystallization of Y6,which drastically decreased short-circuit current and fill factor.These results demonstrate the important role of processing solvent in dictating film morphology,which critically connects with the resultant printed OPV performance.展开更多
基金supported by the National Natural Science Foundation of China(No.22375123)the Shuguang Program of Shanghai Education Development Foundation,the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(No.2022SXTD012)。
文摘Fluorinated fused azobenzene boron(FBAz)is a novel electron-deficient building block for polymer electron acceptors in all-polymer solar cells(all-PSC).The B←N bridging units impart a fixed configuration and low-lying LUMO/HOMO energy.Three polymer acceptor materials(P2f,P3f and P5f)with different fluorine substitution positions by copolymerizing FBAz with indacenodithiophene(IDT),are synthesized and investigated to study the influence of fluorinated forms on the all-polymer solar cell performance.The FBAz units are synthesized in just three steps,facilitating the straightforward production of polymer acceptors P2f,P3f,and P5f.These acceptors exhibit strong light absorption in the visible to near-infrared range of 500-1000nm and possess suitable LUMO/HOMO energy levels of-3.99/-5.66 eV which are very complementary to that(E_(LUMO/HOMO)=-3.59/-5.20 eV)of the widely-used polymer donor poly[(ethylhexylthiophenyl)-benzodithiophene-(ethylhexyl)-thienothiophene](PTB7-Th).All-polymer solar cells(all-PSCs)with PTB7-Th as electron donor and P3f as electron acceptor exhibits highest power conversion efficiencies(PCE)2.70%.When PC_(61)BM is added as the third component,the device efficiency can reach 5.36%.These preliminary results indicate that FBAz is a promising strong electron acceptor for the development of n-type polymer semiconductors,especially in organic photovoltaics(OPVs).To the best of our knowledge,this is the first example demonstrating the unique photovoltaic properties of the N=N double bond as an acceptor material.
基金financially supported by the National Key R&D Program of China(2021YFB3800300)the National Natural Science Foundation of China(22179143 and 22309202)+1 种基金the Jiangsu Funding Program for Excellent Postdoctoral Talentthe Gusu Leading Talents Program(ZXL2023190)。
文摘Integrating high-nickel layered oxide cathodes with aqueous slurry electrode preparation routes holds the potential to simultaneously meet the demands for high energy density and low-cost production of lithium-ion batteries.However,the influence of dual exposure to air and liquid water as well as the heating treatment during aqueous slurry electrode processing on the high-nickel layered oxide electrode is yet to be understood.In this study,we systematically investigate the structural evolution and electro-chemical behaviors when LiNi_(0.83)Mn_(0.05)Co_(0.12)O_(2)(NMC83)is subjected to aqueous slurry processing.It was observed that the crystal structure near the surface of NMC83 is partially reconstructed to contain a mixture of rock-salt and layered phases when exposed to water,leading to the deteriorated rate capability of the NMC83 electrodes.This partial surface reconstruction layer completely converts into a pure rock-salt phase upon cycling,accompanied by the release of O_(2),Ni leaching,catalyzed decomposition of the electrolyte,and the formation of a thick cathode electrolyte interphase layer.The byproducts of the electrolyte and dissolved Ni could shuttle to the Li metal side,causing a crosstalk effect that results in a thick and unstable solid electrolyte interphase layer on the Li surface.These in combination severely undermined the cycling stability of the NMC83 electrodes obtained from the aqueous slurry.A mitigation strategy using molecular self-assembly technique was demonstrated to enhance the surface stability of water-treated NMC83.Our findings offer new insights for tailoring ambient environment stability and aqueous slurry processability for ultra-high nickel layered oxide and other water-sensitive cathode materials.
基金supported by the National Key Research and Development Program of China(No.2023YFB3813000)the National Natural Science Foundation of China(Nos.82071085,82020108011,and 82122014)the Zhejiang Provincial Natural Science Foundation of China(No.LR21H140001).
文摘Periodontitis is an inflammatory disease caused by oxidative stress and initiated by bacterial infection.The endogenous enzyme system is dysfunctional in the periodontitis microenvironment.Currently,traditional clinical treatment cannot efficiently eliminate bacteria or relieve inflammation.To address this issue,we developed ultrasmall ruthenium nanoparticles(US-RuNPs)with multienzyme-like activity.Our results indicated that US-RuNPs with an amplified electric field had a superior photothermal effect to large-sized RuNPs.Thus,US-RuNPs,through photothermal therapy(PTT),acted as“bacterial lysozyme”to eliminate planktonic pathogens and biofilms.In addition,the antioxidant enzyme-like activity of US-RuNPs was greater than that of large-sized RuNPs,and US-RuNPs could scavenge intracellular reactive oxygen species(ROS)and inhibit inflammation-related responses.More importantly,US-RuNPs demonstrated a satisfactory effect against periodontitis in vivo due to their synergistic antibacterial activity through PTT and antioxidant effects even in deep sites,decreasing the alveolar bone loss to root length ratio(ABL/RL)from 70.70%to 20.15%and increasing the collagen volume fraction from 16.88%to 57.64%.Thus,US-RuNPs with approximately 2 nm diameter,mimicking multienzyme activity,have great potential for the treatment of periodontitis.
基金supported by the Beijing Nova Program(No.20220484215)National Key Research and Development Program of China(Nos.2022YFB3504100,2022YFB3506200,2021YFA1500300 and 2022YFA1500146)National Natural Science Foundation of China(Nos.22376217,22208373,22272090 and 22272106)。
文摘Herein,we fabricate an embedding structure at the interface between Pt nanoparticles(NPs)and CeO_(2)-{100}nanocubes with surface defect sites(CeO_(2)-SDS)through quenching and gas bubbling-assisted membrane reduction methods.The in-situ substitution of Pt NPs for atomic-layer Ce lattice significantly increases the amount of reactive oxygen species from 133.68μmol/g to 199.44μmol/g.As a result,the distinctive geometric structure of Pt/CeO_(2)-SDS catalyst substantially improves the catalytic activity and stability for soot oxidation compared with the catalyst with no quenching process,i.e.,its T_(50)and TOF values are 332°C and 2.915 h^(-1),respectively.Combined with the results of experimental investigations and density functional theory calculations,it is unveiled that the unique embedding structure of Pt/CeO_(2)-SDS catalyst can facilitate significantly electron transfer from Pt to the CeO_(2)-{100}support,and induce the formation of interfacial[Ce-O_(x)-Pt_(2)]bond chains,which plays a crucial role in enhancing the key step of soot oxidation through the dual activation of surface lattice oxygen and molecular O_(2).Such a fundamental revelation of the interfacial electronic transmission and corresponding modification strategy contributes a novel opportunity to develop high-efficient and stable noble metal catalysts at the atomic level.
基金supported by the National Key Research and Development Program of China(Nos.2021YFF1200300,2020YFA0909000)National Natural Science Foundation of China(Nos.22025404,32471426)+3 种基金Innovative Research Group of High-Level Local Universities in Shanghai(No.SHSMU-ZLCX20212602)Natural Science Foundation of Shanghai(No.23ZR1438700)Shanghai Municipal Health Commission(No.2022JC027)Shanghai Sailing Program(No.22YF1424400)。
文摘RNA offers distinct advantages for molecular self-assembly as a unique and programmable biomaterial.Recently,single-stranded RNA(ssRNA)origamis,capable of self-folding into defined nanostructures within a single-stranded RNA molecule,are considered a promising platform for immune recognition and therapy.Here,we utilize single-stranded rod RNA origami(Rod RNA-OG)as functional nucleic acid to synthesize valence-programmed RNA structures in a one-pot manner.We discover that the polyvalent RNA origamis are resistant to RNase degradation and can be efficiently internalized by macrophages for subsequent innate immune activation,even in the absence of any external protective agents such as lipids or polymers.The valence-programmed RNA origamis thus hold great promise as novel agonists for immunotherapy.
文摘Designing Fischer-Tropsch synthesis(FTS)catalysts to selectively produce liquid hydrocarbon fuels is a crucial challenge.Herein,we selectively introduced Co nanoparticles(NPs)into the micropores and mesopores of an ordered mesoporous MFI zeolite(OMMZ)through impregnation,which controlled the carbon number distribution in the FTS products by tuning the position of catalytic active sites in differently sized pores.The Co precursors coordinated by acetate with a size of 9.4×4.2×2.5Åand by 2,2'-bipyridine with a size of 9.5×8.7×7.9Å,smaller and larger than the micropores(ca.5.5Å)of MFI,made the Co species incorporated in OMMZ's micropores and mesopores,respectively.The carbon number products synthesized with the Co NPs confined in mesopores were larger than that in micropores.The high jet and diesel selectivities of 66.5%and 65.3%were achieved with Co NPs confined in micropores and mesopores of less acidic Na-type OMMZ,respectively.Gasoline and jet selectivities of 76.7%and 70.8%were achieved with Co NPs confined in micropores and mesopores of H-type OMMZ with Brönsted acid sites,respectively.A series of characterizations revealed that the selective production of diesel and jet fuels was due to the C-C cleavage suppressing of heavier hydrocarbons by the Co NPs located in mesopores.
基金This work was financially supported by MOST(Nos.2022YFA1203001 and 2022YFA1203002)NSFC(Nos.T2321003,22335003 and 22105045)STCSM(Nos.21511104900 and 20JC1414902).
文摘Metal-backboned polymers with anisotropy microstructures are promising for conductive,optoelectronic,and magnetic functional materials.However,the structure-property relationships governing the interplay between the chemical structure and electromagnetic property of the metal-backboned polymer have been rarely investigated.Here we report a carbon/nickel hybrid from metal-backboned polymer to serve as electromagnetic wave-absorbing materials,which exhibit high microwave absorption capacity and tunable absorption band.The presence of nickel backbones promote the generation of heterogeneous interfaces with carbon during calcination,thereby enhancing the wave-absorbing capacity of the carbon/nickel hybrid.The C/Ni hybrids show a minimal reflection loss of-49.1 dB at 13.04 GHz,and its frequency of the absorption band can be adjusted by controlling the thickness of the absorption layer.
基金supported by the National Natural Science Foundation of China (52302292, 52302058, 52302085)the China Postdoctoral Science Foundation (2021M702225)+1 种基金the Anhui Province University Natural Science Research Project (2023AH030093, 2023AH040301)the Startup Research Fund of Chaohu University (KYQD-2023005, KYQD-2023051)。
文摘Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy density.However,uneven Li deposition behavior still occurs at the top of 3D frameworks owing to the local accumulation of Li ions.To promote uniform Li deposition without top dendrite growth,herein,a layered multifunctional framework based on oxidation-treated polyacrylonitrile(OPAN) and metal-organic framework(MOF) derivatives was proposed for rationally regulating the distribution of Li ions flux,nucleation sites,and electrical conductivity.Profiting from these merits,the OPAN/carbon nano fiber-MOF(CMOF) composite framework demonstrated a reversible Li plating/stripping behavior for 500 cycles with a stable Coulombic efficiency of around 99.0% at the current density of 2 mA/cm~2.Besides,such a Li composite anode exhibited a superior cycle lifespan of over 1300 h under a low polarized voltage of 18 mV in symmetrical cells.When the Li composite anode was paired with LiFePO_(4)(LFP) cathode,the obtained full cell exhibited a stable cycling over 500 cycles.Moreover,the COMSOL Multiphysics simulation was conducted to reveal the effects on homogeneous Li ions distribution derived from the above-mentioned OPAN/CMOF framework and electrical insulation/conduction design.These electrochemical and simulated results shed light on the difficulties of designing stable and safe Li metal anode via optimizing the 3D frameworks.
基金the financial support provided by the Development Plan of Science and Technology of Jilin Province,China (YDZJ202301ZYTS280)the Natural Science Foundation of Jilin Province (YDZJ202401316ZYTS)+2 种基金the Innovation Laboratory Development Program of Education Department of Jilin ProvinceIndustry and Information Technology Department of Jilin Province,China (The Joint Laboratory of MXene Materials)MXene Research Support Plan of Jilin 11 Technology Co.,Ltd.China。
文摘The lithium-sulfur reaction can contribute to the chemical electrical energy conversion capacity due to the multi-level ion/electron transfer process. However, the appearance of soluble intermediate products prevents efficient electron transfer, making it impossible to achieve stable cycling and capacity contribution. Restricted catalysis provides a solution for inhibiting the shuttle of soluble lithium polysulfides.Herein, MXene aerogel with optimized channel utilization is designed as S host according to the polysulfide control strategy of localization, adsorption, and catalysis. With the help of the results of oriented channels, the polysulfide conversion process is optimized, providing a comprehensive scheme for inhibiting the shuttle effect. Lithium sulfur catalytic batteries have achieved high capacity and stable cycling.This system provides a comprehensive solution for lithium sulfur reaction catalysis and a new perspective for the functional application of MXene based lithium sulfur batteries.
文摘Chiral carbonyl compounds frequently occur in natural products and pharmaceuticals. Additionally, they serve as important intermediates in organic synthesis. Transition metal-catalyzed asymmetric carbonylative cross-coupling reactions are among the most straightforward and effective methods for synthesizing chiral carbonyl compounds, including esters, amides, and ketones. The advances in asymmetric carbonylative cross-coupling reactions using various O-, N-, C-, and S-containing nucleophiles or electrophiles over the past decade are summarized.
基金National Nature Science Foundation of China(Nos.52025032,52103144 and 523B2026)for their financial supportsupported by the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(No.GZC20231544)。
文摘As one of the most essential components in photocuring system,photoinitiators(PIs)exert a crucial influence on the properties of the cured product.However,commercially available PIs encounter challenges in simultaneously achieving efficient photoinitiation performance and excellent light absorption properties,significantly limiting their applications in various fields.Here,two bis-chalcones and four corresponding oxime esters(OXEs)were designed and synthesized as highly efficient PIs.Featuring a structure comprising bis-chalcone and two diphenyl sulfides,the conjugated systems in these compounds enhance their light-absorption properties in near-ultraviolet and visible region,effectively.Both the frontier molecular orbital simulations and excited state calculations suggest the contribution of sulfur atoms to electron delocalization and the formation of conjugated structure.Due to the high reactivity of the N–O bond in OXE moiety,the four OXEs exhibit exceptional free radical photoinitiating ability in commercial acrylic monomers/oligomers with LED@365nm as light source.Notably,one of them demonstrates superior performance in the photoinitiation of multifunctional crosslinker,achieving more than 70%conversion within 3 s,coupled with outstanding absorption at 365 nm.These chalcone-based OXEs are considered to exert significant potential in the realm of free radical photocuring.
基金financially supported by the National Natural Science Foundation of China(No.22171182)Sichuan Tianfu Emei Plan.
文摘Control crosslink network and chain connectivity are essential to develop shape memory polymers(SMPs)with high shape memory capabilities,adjustable response temperature,and satisfying mechanistical properties.In this study,novel poly(ε-caprolactone)(PCL)-poly(2-vinyl)ethylene glycol(PVEG)copolymers bearing multi-pendant vinyl groups is synthesized by branched-selective allylic etherification polymerization of vinylethylene carbonate(VEC)with linear and tetra-arm PCLs under a synergistic catalysis of palladium complex and boron reagent.Facile thiol-ene photo-click reaction of PCL-PVEG copolymers with multifunctional thiols can rapidly access a serious crosslinked SMPs with high shape memory performance.The thermal properties,mechanical properties and response temperature of the obtained SMPs are tunable by the variation of PCL prepolymers,vinyl contents and functionality of thiols.Moreover,high elastic modulus in the rubbery plateau region can be maintained effectively owing to high-density topological networks of the PCL materials.In addition,the utility of the present SMPs is further demonstrated by the post-functionalization via thiol-ene photo-click chemistry.
基金financially supported by the National Natural Science Foundation of China(No.52473097)the Fundamental Research Funds for the Central Universities(No.24X010301678)Shanghai Jiao Tong University 2030 Initiative(No.WH510363002/002)。
文摘Incorporating a low density of ester units into the backbone of polyethylene materials enhances their sustainability and recyclability while maintaining the main material properties of polyethylenes.Here we report a new way to access degradable polyethylene materials with a low content of in-chain ester units via mechanochemical backbone editing.Initially,ester groups are incorporated as side groups through catalytic copolymerization of ethylene with a cyclobutene-fused lactone monomer(CBL),yielding polyethylene materials with high molecular weights and adjustable thermomechanical properties.Subsequent solid-state ball-milling treatment selectively introduces side-chain ester groups into the main chain of the polyethylene materials via force-induced cycloreversion of the cyclobutane units.Under acidic conditions,hydrolysis of the resultant polyethylene materials with in-chain ester units facilitates further degradation into oligomers.
基金This work was supported by the National Natural Science Foundation of China(Nos.22225501 and 52073173)the Key Research Projects of Universities in Henan Province(No.23A530005)+2 种基金the National Key Laboratory of Biobased Transport Fuel Technology(No.KFKT2022002)of ChinaProgram of Shanghai Academic/Technology Research Leader(No.23XD1431700)Shanghai Engineering Research Center of Specialized Polymer Materials for Aerospace(No.18DZ2253500).
文摘Using natural resources to construct electrocatalysts for biomass conversion and elucidating their catalytic mechanisms are of great significance,but have remained challenging.Here,a series of two-dimensional(2D)biomass-based Pb/PbO@C nanoparticles catalysts with Pb/PbO anchored on carbon nanosheets were synthesized using natural-derived humate as the precursor.By adjusting the carbonization temperature,an electron-deficient Pb0/Pb^(2+)dual-center-site catalyst can be achieved.The optimized Pb/PbO@C catalyst showed an excellent performance for the electrochemical hydrogenation of 5 hydroxymethylfurfural(HMF)to high value-added 2,5 bis(hydroxymethyl)furan(BHMF),with high Faradaic efficiency(FE:91.9%)and selectivity(Sel:89.7%),achieving comparable performance to those of the reported noble metal-based electrocatalysts.Mechanism study revealed that the electron-deficient Pb^(0)/Pb^(2+)dual-center-site provided abundant Lewis acidic sites and promoted the dissociation of water to the active hydrogen(H^(*))species,thus enhancing the adsorption of HMF on Pb^(2+)sites and the coverage of H^(*)species on Pb0 sites.The high coverage of H*species and the synergistic effect of dual-center sites substantially promoted the binding of H*and HMF to form H-HMF^(*)and inhibited the recombination of H^(*)species,thereby accelerating the reaction kinetics of HMF reduction.
基金Financial support from the National Natural Science Foundation of China(No.22271060)。
文摘The bicarbonate-formate(HCO_(3)−–HCO_(2)−)interconversion provides a promising cycle for a conveniently accessible hydrogen storage system via reversible dehydrogenation and hydrogenation processes.Existing catalytic systems often use organic solvents,tedious optimization as well as manipulation of pH values,solvent,pressure and various additives.Herein,we present an operational,robust,safe and cost-effective catalytic system for hydrogen storage and liberation.We have established a unique catalytic system with two different solid organometallic assemblies(NHC-Ru and NHC-Ir)that facilitate the reversible transformation between sodium formate and bicarbonate in aqueous solutions collaboratively and efficiently.Notably,the NHC-Ru catalyst is privileged for the hydrogenation of sodium bicarbonate,whereas the NHC-Ir component enables the dehydrogenation of sodium formate,all in a single reaction vessel.What sets this system apart is its simplicity.The H_(2)discharging and recharging is simply regulated by heating the mixture with or without H_(2).Remarkably,this process requires no extra additives or supplementary treatments.Moreover,the reversible hydrogen storage system is durable and can be reused for over 30 cycles without a discernible decline in activity and selectivity.The strategic paradigm in this study shows significant practical potential in hydrogen fuel cell applications.
基金financially supported by the National Natural Science Foundation of China (Nos. 22075130 and 21875102)the Fundamental Research Funds for the Central Universities
文摘Solid-state electrolytes are considered to be the vital part of the next-generation solid-state batteries(SSBs),due to their high safety and long operation life span.However,the two major factors that impede the expected performance of batteries are:the easy formation of lithium dendrites due to the concentration gradient of anions,and the low ionic conductivity at room temperature,which prevents reaching ideal electrochemical performance.Single-ion quasi-solid-state electrolytes(SIQSSEs)could provide higher safety and energy density,owing to absence of anion concentration gradient and solvent,as well as good lithium-ion transport ability.The porous covalent organic frameworks(COFs)are beneficial for con-structing appropriate lithium-ion transport pathway,due to the ordered 1D channel.In addition,the boroxine COFs(COF-5)offers strong ability of withdrawing anion part of lithium salt.Last but not the least,boron atom could play the role of coordinate site due to its electron deficiency.These advantages afford an opportunity to obtain a SIQSSE with high ionic conductivity and high lithium transference number(LTN)simultaneously.The COF-5 based SIQSSEs delivered a high ionic conductivity of 6.3×10^(-4)S·cm^(-1),with a high LTN of 0.92 and a wide electrochemical stable window(ESW)of 4.7 V at room temperature.The LiFePO4(LFP)/Li cells,which was assembled with COF-5 based SIQSSE,exhibited outstanding long cycle stability,high initial capacity and favorable rate performance.The results indicated COFs could be an ideal material for single-ion solid-state electrolytes in next-generation batteries.
基金supported by the National Key Research and Development Program of China(2021YFA0909400)the National Natural Science Foundation of China(22425505,32301099,and 21834007)+2 种基金the Shanghai Sailing Program(22YF1424200)the Interdisciplinary Program of Shanghai Jiao Tong University(YG2022QN032)the Xiangfu Lab Research Project(XF012022E0100).
文摘Immunization has long played essential roles in preventing diseases.However,the desire for precision delivery of vaccines to boost a robust immune response remains largely unmet.Here,we describe the use of acupoint delivery of nanovaccines(ADN)to elicit dual-niche immunological priming.ADN can simultaneously stimulate mast cell-assisted maturation of dendritic cells at the acupoint and enable direct delivery of nanovaccines into the draining lymph nodes.We demonstrate that ADN not only provokes antigen presentation by lymph node-resident CD8α^(+)dendritic cells,but also induces the accumulation of nanovaccines in B-cell zones,amplifying antigen-specific cytotoxic T lymphocyte responses and immunoglobulin G antibody expression in draining lymph nodes.ADN also generates systemic immune responses by causing immune memory and preventing T-cell anergy in the spleen.Further supported by evoking effective antitumor responses and high-level antiviral antibodies in mice,ADN provides a simple yet versatile platform for advanced nanovaccination.
基金We acknowledge financial support by the National Natural Science Foundation of China(32071374,32000985,81761148029,81620108028)Program of Shanghai Academic Research Leader under the Science and Technology Innovation Action Plan(21XD1422100)+3 种基金Leading Talent of“Ten Thousand Plan”-National High-Level Talents Special Support Plan,One Belt and One Road International Cooperation Project from Key Research and Development Program of Zhejiang Province(2019C04024)the Zhejiang Provincial Natural Science Foundation of China(LR22C100001,LGF19C100002,LQ21H300003)Zhejiang Province Medical and Health Science Research Project(2021KY666),and Zhejiang Pharmaceutical Association(2019ZYY12)Open access funding provided by Shanghai Jiao Tong University
文摘The structural change-mediated catalytic activity regulation plays a significant role in the biological functions of natural enzymes.However,there is virtually no artificial nanozyme reported that can achieve natural enzyme-like stringent spatiotemporal structure-based catalytic activity regulation.Here,we report a subnanostructural transformable gold@ceria(STGC-PEG)nanozyme that performs tunable catalytic activities via near-infrared(NIR)light-mediated sub-nanostructural transformation.The gold core in STGC-PEG can generate energetic hot electrons upon NIR irradiation,wherein an internal sub-nanostructural transformation is initiated by the conversion between CeO;and electron-rich state of CeO;-x,and active oxygen vacancies generation via the hot-electron injection.Interestingly,the sub-nanostructural transformation of STGC-PEG enhances peroxidase-like activity and unprecedentedly activates plasmon-promoted oxidase-like activity,allowing highly efficient low-power NIR light(50 m W cm;)-activated photocatalytic therapy of tumors.Our atomic-level design and fabrication provide a platform to precisely regulate the catalytic activities of nanozymes via a light-mediated sub-nanostructural transformation,approaching natural enzyme-like activity control in complex living systems.
基金This work was financially supported by the National Natrual Science Foundation of China(Nos.21901161 and 22071152)Natural Science Foundation of Shanghai(No.20ZR1429200)+1 种基金the China Postdoctoral Science Foundation(No.2020M671094)Basic Research Program of Xi'an Jiaotong University(No.XZY022020018).
文摘Herein,we designed and constructed two metallacycles,1 and 2,to illustrate the conformational effect of isomeric AIE fluoropho res on the platfo rm of supramolecular coordination complexe s(SCCs).Specifically,the dangling phenyl rings in TPE units of the metallacycle 1 align completely outside the main cyclic structure,while in the metallacycle 2,these phenyl rings align half inside and half outside.The experimental results showed that two metallacycles exhibited different behaviors in terms of AIE fluorescence and chemical sensing,which could be attributed to the subtle structural difference of the TPE units.This work repre sents the unification of topics such as self-assembly,AIE,and chemical sensing,and further promotes the understanding for the structure-property relationship of isomeric AIE fluorophores.
基金financially supported by the National Natural Science Foundation of China(Nos.51973110,21734009,21905102 and 22109094)the Program of Shanghai Science and Technology Commission science and technology innovation action plan(Nos.20ZR1426200,20511103800,20511103802 and 20511103803)+2 种基金the Natural Science Foundation of Shandong Province(No.ZR2019LFG005)the Key research project of Shandong Province(No.2020CXGC010403)the Center of Hydrogen Science,Shanghai Jiao Tong University,China。
文摘The morphology manipulation of the active layers is important for improving the performance of organic photovoltaics(OPVs).The choice of processing solvent has great impact on the crystallization and phase separation during film formation,since solvent properties,including solvent effect on molecular crystallization,boiling point,and interaction parameters,can directly change the evolution pathways associated with thermodynamics and kinetics.Therefore,revealing the underlying solvent-regulated morphology mechanism is potential to provide guiding strategies for device optimization.In this study,chloroform,chlorobenzene,and toluene are used to process PM6:Y6 blends by slot-die printing to fabricate OPV devices.The chloroform printed film forms a fibrillar network morphology with enhanced crystallization,facilitating exciton dissociation,charge transport and extraction,resulting in an optimal power conversion efficiency of 16.22%.However,the addition of the additive chloronaphthalene in chloroform solution leads to over-crystallization of Y6,and thus,increasing domain size that exceeds the exciton diffusion length,resulting in lower device efficiency.In addition,both the chlorobenzene and toluene suppress the crystallization of Y6,which drastically decreased short-circuit current and fill factor.These results demonstrate the important role of processing solvent in dictating film morphology,which critically connects with the resultant printed OPV performance.
