Covalent organic frameworks(COFs)have great potential as adsorbents due to their customizable functionality,low density and high porosity.However,COFs powder exists with poor processing and recycling performance.Moreo...Covalent organic frameworks(COFs)have great potential as adsorbents due to their customizable functionality,low density and high porosity.However,COFs powder exists with poor processing and recycling performance.Moreover,due to the accumulation of COFs nanoparticles,it is not conducive to the full utilization of their surface functional groups.Currently,the strategy of COFs assembling into aerogel can be a good solution to this problem.Herein,we successfully synthesize composite aerogels(CSR)by in-situ self-assembly of two-dimensional COFs and graphene based on crosslinking of sodium alginate.Sodium alginate in the composite improves the mechanical properties of the aerogel,and graphene provides a template for the in-situ growth of COFs.Impressively,CSR aerogels with different COFs and sizes can be prepared by changing the moiety of the ligand and modulating the addition amount of COFs.The prepared CSR aerogels exhibit porous,low density,good processability and good mechanical properties.Among them,the density of CSR-N-1.6 is only 5 mg/cm3,which is the lowest density among the reported COF aerogels so far.Due to these remarkable properties,CSR aerogels perform excellent adsorption and recycling properties for the efficient and rapid removal of organic pollutants(organic dyes and antibiotics)from polluted water.In addition,it is also possible to visually recognize the presence of antibiotics by fluorescence detection.This work not only provides a new strategy for synthesizing COF aerogels,but also accelerates the practical application of COF aerogels and contributes to environmental remediation.展开更多
A sp^(2) carbon-conjugated covalent organic framework (BDATN) was modified through γ-ray radiation reduction and subsequent acidification with hydrochloric acid to yield a novel functional COF (named rBDATN-HCl) for ...A sp^(2) carbon-conjugated covalent organic framework (BDATN) was modified through γ-ray radiation reduction and subsequent acidification with hydrochloric acid to yield a novel functional COF (named rBDATN-HCl) for Cr(Ⅵ) removal.The morphology and structure of rBDATN-HCl were analyzed and identified by SEM,FTIR,XRD and solid-state13C NMR.It is found that the active functional groups,such as hydroxyl and amide,were introduced into BDATN after radiation reduction and acidification.The prepared rBDATN-HCl demonstrates a photocatalytic reduction removal rate of Cr(Ⅵ) above 99%after 60min of illumination with a solid-liquid ratio of 0.5 mg/mL,showing outstanding performance,which is attributed to the increase of dispersibility and adsorption sites of r BDATN-HCl.In comparison to the cBDATN-HCl synthesized with chemical reduction,rBDATN-HCl exhibits a better photoreduction performance for Cr(Ⅵ),demonstrating the advantages of radiation preparation of rBDATN-HCl.It is expected that more functionalized sp^(2) carbon-conjugated COFs could be obtained by this radiation-induced reduction strategy.展开更多
Zinc-ion batteries(ZIBs)are inexpensive and safe,but side reactions on the Zn anode and Zn dendrite growth hinder their practical applications.In this study,1,3,5-triformylphloroglycerol(Tp)and various diamine monomer...Zinc-ion batteries(ZIBs)are inexpensive and safe,but side reactions on the Zn anode and Zn dendrite growth hinder their practical applications.In this study,1,3,5-triformylphloroglycerol(Tp)and various diamine monomers(p-phenylenediamine(Pa),benzidine(BD),and 4,4"-diamino-p-terphenyl(DATP))were used to synthesize a series of two-dimensional covalent-organic frameworks(COFs).The resulting COFs were named TpPa,TpBD,and TpDATP,respectively,and they showed uniform zincophilic sites,different pore sizes,and high Young's moduli on the Zn anode.Among them,TpPa and TpBD showed lower surface work functions and higher ion transfer numbers,which were conducive to uniform galvanizing/stripping zinc and inhibited dendrite growth.Theoretical calculations showed that TpPa and TpBD had wider negative potential region and greater adsorption capacity for Zn2+than TpDATP,providing more electron donor sites to coordinate with Zn^(2+).Symmetric cells protected by TpPa and TpBD stably cycled for more than 2300 h,whereas TpDATP@Zn and the bare zinc symmetric cells failed after around 150 and200 h.The full cells containing TpPa and TpBD modification layers also showed excellent cycling capacity at 1 A/g.This study provides comprehensive insights into the construction of highly reversible Zn anodes via COF modification layers for advanced rechargeable ZIBs.展开更多
The light-driven CO_(2)reduction reaction(CO_(2)RR)to CO is a very effective way to address global warming.To avoid competition with water photolysis,metal-free gas-solid CO_(2)RR catalysts should be investigated.Cova...The light-driven CO_(2)reduction reaction(CO_(2)RR)to CO is a very effective way to address global warming.To avoid competition with water photolysis,metal-free gas-solid CO_(2)RR catalysts should be investigated.Covalent organic frameworks(COFs)offer a promising approach for CO_(2)transformation but lack high efficiency and selectivity in the absence of metals.Here,we have incorporated a pyridine nitrogen component into the imine-COF conjugated structure(Tp Pym).This innovative system has set a record of producing a CO yield of 1565μmol g^(-1)within 6 h.The soft X-ray absorption fine structure measurement proves that Tp Pym has both better conjugation and electron cloud enrichment.The electronic structure distribution delays the charge-carrier recombination,as evidenced by femtosecond transient absorption spectroscopy.The energy band diagram and theoretical calculation show that the conduction-band potential of Tp Pym is lower and the reduction reaction of CO_(2)to CO is more likely to occur.展开更多
The advancement of functional adhesives featuring recyclable and repairable properties is of great significance in interfacial science and engineering.Herein,a series of high-strength,recyclable fluorine-containing ad...The advancement of functional adhesives featuring recyclable and repairable properties is of great significance in interfacial science and engineering.Herein,a series of high-strength,recyclable fluorine-containing adhesives(ESOx-FPF)were designed and synthesized by crosslinking two prepolymers,FPF-B(derived from side-chain fluorinated diol,isocyanate,and aminoboric acid)and ESO-B(synthesized from biobased epoxy soybean oil and aminoboric acid),through dynamic boro-oxygen bonds.The resulting adhesive exhibited an optimal tensile strength of 42 MPa and the shear strength on steel plates reached as high as 3.89 MPa.More importantly,benefiting from the dynamic reversibility of the boron-oxygen bonds along with the hydrogen bonds interaction,ESOx-FPF can be welded with the assistance of solvents and recycled for multiple cycles.The outstanding healing efficiency and excellent reprocessability of these functional adhesives were confirmed by mechanical testing.Moreover,the as-prepared adhesives demonstrated universal and remarkable adhesion to various substrates,such as aromatic polyamide,aluminum plates and polycarbonate,meanwhile,they could be easily disassembled and recycled using ethanol without damaging the substrates surface.This study not only provides a simple strategy for the synthesis of eco-friendly adhesives with weldable and recyclable properties,but also sheds light on the development of other functional materials utilizing dynamic covalent chemistry.展开更多
The cyclic guanosine monophosphate-adenosine monophosphate synthase and the stimulator of interferon genes(cGAS-STING)has emerged as a promising target for cancer immunotherapy.However,the development of natural STING...The cyclic guanosine monophosphate-adenosine monophosphate synthase and the stimulator of interferon genes(cGAS-STING)has emerged as a promising target for cancer immunotherapy.However,the development of natural STING agonists is impeded by several challenges,including limited biostability,poor pharmacokinetics,and inefficient cytosolic delivery.Herein,we meticulously designed a doublelayer polyethylenimine(PEI)modified nanoscale covalent organic polymer(CPGP)for efficient delivery of 23cyclic guanosine monophosphate-adenosine monophosphate(cGAMP),a natural STING agonist.The double-layer PEI structured CPGP enhanced both the loading capacity and stability of cGAMP.Furthermore,CPGP improved the intracellular delivery efficiency and amplified the activation of STING pathway for the secretion of type-I interferon and pro-inflammatory cytokines.In contrast,single-layered nanoparticles failed to permit stable loading and intracellular delivery of cGAMP for immune response.The nano-STING agonist also mitigated the immunosuppressive tumor microenvironment(TME)by reducing regulatory T cells and polarizing M2 macrophages to the M1 phenotype,thereby creating an immune-supportive TME to enhance adaptive immune responses.The combination of CPGP and immune checkpoint blockers showed synergistic effect,further enhancing the inhibition effect on tumor growth.This double-layer PEI modified CPGP may offer a generalizable platform for other natural dinucleotide STING agonists to overcome the cascade delivery barriers,augmenting immune activation for tumor immunotherapy.展开更多
The high conductivity of electrocatalyst can eliminate the Schottky energy barrier at the interface of heterogeneous phases during an electrocatalytic reaction and accelerate the rapid electron transfer to the catalyt...The high conductivity of electrocatalyst can eliminate the Schottky energy barrier at the interface of heterogeneous phases during an electrocatalytic reaction and accelerate the rapid electron transfer to the catalytic active center.Therefore,the electronic conductivity is a vital parameter for oxygen reduction reaction(ORR).Covalent triazine frameworks(CTFs)have shown great potential application as electrocatalysts in ORR with a merit of the diverse building blocks.However,the intrinsic low conductivity and high impedance of CTFs could be significant setbacks in electrocatalytic application.Herein,CTFs were constructed by introducing F and N co-modification for efficient 2e^(-)ORR.Compared with the pristine CTF,the co-presence of F,N could increase the conductivity obviously by 1000-fold.As a result,F-N-CTF exhibits enhanced catalytic performance of H_(2)O_(2)generation and selectivity towards reaction pathways.This work reveals the importance of conductivity optimization for CTFs and provides guidance for designing high conductivity non-metallic organic semiconductor catalysts for 2e^(-)ORR.展开更多
Flexible covalent organic framework(COF)film has drawn much attention as a promising functional material due to their unique molecular structure and self-supporting property.However,the traditional solvothermal method...Flexible covalent organic framework(COF)film has drawn much attention as a promising functional material due to their unique molecular structure and self-supporting property.However,the traditional solvothermal method of synthesizing flexible COF film is usually complicated,long-term duration and energy-consuming,making it unsuitable for scalable preparation.To address these limitations,a new method combining electrospinning and sacrificial template is proposed to quickly produce triazinebased COF fiber films at room temperature.The method is easy to operate and has a short reaction time(minimum 0.5 h)without dehydration and deoxygenation processes at room temperature,making it suitable for large-scale production(20 cm×30 cm).Different from the unprocessable of COF powder,COF films not only have good flexibility and mechanical properties,but also can be patterned with multiple functions to adapt to various application scenarios.Moreover,the functionality of triazine-structured COF is retained,enabling the use of the films in energy conversion and storage applications.Triazine-based COFs naturally have scalable conjugated structure,thus showing potential photocatalytic probability.Furthermore,the large pore structure of COF films enables loading of phase change materials endowing comprehensive properties of thermal management and flame retardance.This study proposes a strategy for the rapid synthesis of COF fiber films at room temperature and paves the way for multifunctional and high-performance COF based materials.展开更多
Prostaglandin E2(PGE2) serves as the ultimate mediator of fever induced by infiammatory factors. In contrast to cyclooxygenase inhibitors that suppress arachidonic acid metabolism, antipyretic herbs possess a well-est...Prostaglandin E2(PGE2) serves as the ultimate mediator of fever induced by infiammatory factors. In contrast to cyclooxygenase inhibitors that suppress arachidonic acid metabolism, antipyretic herbs possess a well-established clinical history in effectively managing fever. However, the specific mechanisms underlying their efficacy remain unclear. Following the screening for lead compounds that inhibit PGE2from antipyretic herbs, alkynylated active molecule probes were designed and synthesized to track and identify potential targets. The target investigation revealed that three antipyretic compounds, namely cinnamaldehyde, 2,4-decadienal, and perillaldehyde, containing α,β-unsaturated aldehyde groups irreversibly targeted the microsomal PGES1-TM4 helix(m PGES1-TM4) at Ser139. This specific interaction effectually inhibited PGE2 production in the cerebral vasculature, leading to exert potent antipyretic effects.α,β-Unsaturated aldehydes targeting m PGES1-TM4 offer a new approach for antipyretic effects with significant potential for various applications.展开更多
In this work,a novel electrochemical sensor based on covalent organic framework@carbon black@molecularly imprinted polydopamine(COF@CB@MPDA)was developed for selective recognition and determination of ciprofloxacin(CF...In this work,a novel electrochemical sensor based on covalent organic framework@carbon black@molecularly imprinted polydopamine(COF@CB@MPDA)was developed for selective recognition and determination of ciprofloxacin(CF).COF@CB@MPDA possessed good water dispersibility and was synthesized by the selfpolymerization of dopamine under alkaline conditions in the presence of the COF,CB and CF.The high surface area COF enhanced the adsorption of CF,whilst CB gave the composites high electrical conductivity to improve the sensitivity of the proposed COF@CB@MPDA/glassy carbon electrode(GCE)sensor.The specific recognition of CF by COF@CB@MPDA involved hydrogen bonding and van der Waals interactions.Under optimized conditions,the sensor showed a good linear relationship with CF concentration over the range of 5.0×10^(–7)and 1.0×10^(–4)mol/L,with a limit of detection(LOD)of 9.53×10^(–8)mol/L.Further,the developed sensor exhibited high selectivity,repeatability and stability for CF detection in milk and milk powders.The method used to fabricate the COF@CB@MPDA/GCE sensor could be easily adapted for the selective recognition and detection of other antibacterial agents and organic pollutants in the environment.展开更多
Dimensionality has great influence on the photo/electro-catalysts properties of covalent organic frameworks(COFs) because of the different electronic and porous structures.However,very rare attention has been paid on ...Dimensionality has great influence on the photo/electro-catalysts properties of covalent organic frameworks(COFs) because of the different electronic and porous structures.However,very rare attention has been paid on the dimensionality and function correlations of COF materials.In the present work,one new two-dimensional phthalocyanine COF,namely 2D-NiPc-COF,and one new three-dimensional phthalocyanine COF,namely 3D-NiPc-COF,were fabricated according to the imide reaction between tetraanhydrides of 2,3,9,10,16,17,23,24-octacarboxyphthalocyaninato nickel(Ⅱ) with [2,2-bipyridine]-5,5-diamine and tetrakis(4-aminophenyl) methane,respectively.The crystalline structures of both COFs are verified by the powder X-ray diffraction analysis,computational simulation,and high resolution transmission electron microscopy measurement.Notably,3D-NiPc-COF with dispersed conjugated modules has high utilization efficiency of NiPc electroactive sites of 26.8%,almost two times higher than the in-plane stacking2D-NiPc-COF measured by electrochemical measurement,in turn resulting in its superior electrocatalytic performance with high CO_(2)-to-CO Faradaic efficiency over 90% in a wide potential window,a large partial CO current density of-13.97 mA/cm^(2) at-0.9 V(vs.reversible hydrogen electrode) to 2D-NiPc-COF.Moreover,3D-NiPc-COF has higher turnover number and turnover frequency of 5741.6 and 0.18 s^(-1) at-0.8 V during 8 h lasting measurement.The present work provides an example for the investigation on the correlation between dimensionality and electrochemical properties of 2D and 3D phthalocyanine COFs.展开更多
Covalent organic cages(COCs)are three-dimensional organic molecules with permanent cavities,known for their ordered pore structures,excellent processability,and modular design.They have shown significant potential in ...Covalent organic cages(COCs)are three-dimensional organic molecules with permanent cavities,known for their ordered pore structures,excellent processability,and modular design.They have shown significant potential in applications such as gas adsorption,molecular separation,and catalysis.Introducing chiral elements into COCs results in chiral COCs with confined chiral cavities,which endows them with unique chiral functions and expands their application prospects.This review summarizes the research progress on chiral covalent organic cages,focusing on strategies for incorporating chiral elements,the structures and synthesis methods of representative chiral COCs,and advancements in their chiral functions.Additionally,we provide perspectives on future research directions.We hope this review will inspire further interest and creativity among researchers in the field of chiral molecular cages,leading to the development of materials with unique structures and functions.展开更多
Slippery liquid-infused porous surfaces(SLIPS)with exceptional liquid repellency and extremely low sliding angles demonstrate significant potential for applications in anti-corrosion,anti-fouling,and anti-scaling.Howe...Slippery liquid-infused porous surfaces(SLIPS)with exceptional liquid repellency and extremely low sliding angles demonstrate significant potential for applications in anti-corrosion,anti-fouling,and anti-scaling.However,the poor stability of the oil layer restricts its practical applications.Herein,a durable SLIPS coating with highly stable oil layer was developed by combining hierarchical porous structures with covalent interpenetrating networks and multiple interfacial interactions.The hierarchical porous structure was constructed via urea thermal decomposition with in situ hybridization of SiO_(2)and embedded carbon nanotubes(CNTs).Furthermore,the oil layer was chemically immobilized on the coating surface using methylenediphenyl diisocyanate(MDI)as a molecular bridge,leveraging interfacial covalent bonding andπ-OH interactions,which significantly enhanced its anti-corrosion properties,with an initial|Z|_(0.01 Hz)of1.22×10^(8)Ωcm^(2).Dynamic scaling experiments revealed a 96.47%improvement in scaling inhibition efficiency compared to conventional superhydrophobic coatings,showing its excellent anti-scaling properties.Owing to the durability and liquidity of oi layer,the prepared FEVE-SiO_(2)/CNTs@MDI SLIPS coating maintained outstanding slippery performance(water sliding angle<10°)even after 14 days of underwater immersion.Additionally,the coating also exhibited excellent thermal stability(120°C),remarkable shear resistance(5000 rpm),and ultraviolet resistance performance.Therefore,the prepared FEVE-SiO_(2)/CNTs@MDI SLIPS coating has broad practical application prospects in the field of industrial oilfield pipeline protection.展开更多
Porous materials are excellent adsorbents for the removal of organic dyes from sewage and play a significant role in environmental restoration.Herein,two ferrocene(Fc)-based covalent organic frameworks(Fc-COFs),namely...Porous materials are excellent adsorbents for the removal of organic dyes from sewage and play a significant role in environmental restoration.Herein,two ferrocene(Fc)-based covalent organic frameworks(Fc-COFs),namely FcTF-COF and FcBD-COF,are successfully synthesized for the first time through a solvothermal method,and the obtained Fc-COFs powders are used to adsorb Congo red(CR)from water.The results show that both FcTF-COF and FcBD-COF have superb adsorption performance towards CR with ultrahigh adsorption capability of 1672.2 mg g−1 and 1983.7 mg g−1 at pH=4.0,respectively,outperforming the majority of the reported solid porous adsorbents.The maximum adsorption of both Fc-COFs agrees with the Sips adsorption isothermal model,indicating that their adsorption was dominated by heterogeneous adsorption.The Coulombic interactions,hydrogen bonding,π-πinteractions and ion-dipolar interactions should all contribute to their ultrahigh CR adsorption capability and high-pH resistance performance regardless of the pH in the range of 4-9.In addition,after five cycles,both COFs still remain their exceptional high CR adsorption capabilities.This study offers a prospective organic porous adsorbent with promising applications for organic dye removal in sewage processing.展开更多
Noteworthy challenges such as severe side reactions,interfacial instability,and dendrite growth have plagued rechargeable alkali metal batteries for a long time.Alleviating the plight necessitates innovative membranes...Noteworthy challenges such as severe side reactions,interfacial instability,and dendrite growth have plagued rechargeable alkali metal batteries for a long time.Alleviating the plight necessitates innovative membranes capable of modulating ion transport and establishing stable interfaces.The exploration of implemented membranes with thermal/mechanical and electrochemical stability is crucial for achieving high-performance and safe alkali metal batteries.Crystalline covalent organic framework(COF)membranes have emerged as promising materials for next-generation energy storage systems due to their tunable porosity and exceptional physicochemical properties.This review specifically examines the critical role of COF membranes in enabling sustainable alkali metal(Li/Na/K)batteries,with a particular focus on design principles,performance advantages,and key challenges of COF membranes.The discussion emphasizes structure-property relationships specifically relevant to rechargeable battery applications,supported by recent decades of research.Impressively,this mini review further identifies three critical research frontiers:reticular chemistry-guided materials design,multifunctional composite architectures,and in-situ characterization techniques.This targeted analysis provides actionable insights for developing COF membranes that address the fundamental limitations of current alkali metal battery technologies.展开更多
Stimuli-responsive two-dimensional (2D) covalent organic frameworks (COFs) with precise structures and permanent porosity have been employed as platforms for sensors. The slight change of backbones inside frameworks l...Stimuli-responsive two-dimensional (2D) covalent organic frameworks (COFs) with precise structures and permanent porosity have been employed as platforms for sensors. The slight change of backbones inside frameworks leads to different electronic states by external stimuli, such as solvent, pH, and water. Herein, we introduced an alkynyl-based building block (ETBA) with high planarity to synthesize two imine-based alkynyl-COFs (ETBA-TAPE-COF and ETBA-PYTA-COF) with high yield, good crystallinity, and chemical stability. Due to the presence of acetylene bonds, ETBA-TAPE-COF does not adopt the completely overlapping AA stacking mode. Slight interlayer displacement occurs along the parallel direction relative to the acetylene linkages, which facilitates lower configurational energy. Additionally, the introduction of pyrene group contributes to high π-electron mobility of ETBA-PYTA-COF. The interactions between electron-withdrawing group (ETBA) and electron-donating group (PYTA) during the processes of protonation and intramolecular charge transfer (ICT) endow ETBA-PYTA-COF with excellent acidochromic and solvatochromic properties, respectively. Based on this, a fluorescence sensor is successfully established, which can be used for rapid response to trace amounts of water in organic solvents. In contrast, ETBA-TAPE-COF does not exhibit these photophysical properties due to its higher HOMO–LUMO gap compared to ETBA-PYTA-COF. This work proposes a new strategy for designing and preparing COFs with unique photophysical properties without introducing additional functional groups.展开更多
Covalent organic frameworks(COFs),as a burgeoning class of crystalline porous materials have attracted widespread interest due to their designable structures and customized functions.However,the solvothermal synthesis...Covalent organic frameworks(COFs),as a burgeoning class of crystalline porous materials have attracted widespread interest due to their designable structures and customized functions.However,the solvothermal synthesis of COFs is often time-consuming and conducted at a high temperature within a sealed vessel,and also requires a large amount of poisonous solvents,which is generally not available for scaling-up production and commercial application.In recent years,great efforts have been made to explore simple,green,and efficient approaches for COFs synthesis.In this comprehensive review,we summarized the advances in emergent strategies by highlighting their distinct features.Fundamental issues and future directions are also discussed with the object of bringing implications for large-scale and sustainable fabrication of COFs.展开更多
The uneven deposition and high reactivity of lithium-metal anode(LMA)lead to uncontrollable dendrite growth,low Coulombic efficiency,and safety concerns,hindering their commercialization.Here,a representative polar-ri...The uneven deposition and high reactivity of lithium-metal anode(LMA)lead to uncontrollable dendrite growth,low Coulombic efficiency,and safety concerns,hindering their commercialization.Here,a representative polar-rich-group triazine-based covalent organic framework(COF-TzDha)with a desolvation effect is designed as an interlayer for stable,dendrite-free LMA.The abundant triazine rings in COFTzDha as a donor effectively attract lithium ions,while the one-dimensional nanopore structure facilitates lithium-ion migration.The periodic arrangement of polar groups(-OH)in the backbone interacts with electrolyte components(DOL,DME,TFSI-)to form a hydrogen bonding network that slows solvent molecules transport.Therefore,COF-TzDha effectively desolvates lithium ions from the solvent sheath,promoting uniform lithium ion flux and Li plating/stripping.Theoretical calculations verify that COFTzDha with abundant adsorption sites and strong adsorption energy facilitates lithium ion desolvation.Consequently,the introduction of COF-TzDha obtains a high ion mobility(0.75).The Li|COF@PP|Li symmetric cell cycles stably for over 1200 h at 4 mA cm^(-2)/4.0 mA h cm^(-2).The Li|COF@PP|LiFePO_(4)full cell also displays highly stable cycling performance with 600 cycles(75.5%capacity retention,~100% Coulombic efficiency)at 1 C.This work verifies an effective strategy for inducing uniform Li deposition and achieving dendrite-free,stable LMA using a polar-rich-group COF interlayer with a desolvation effect.展开更多
Photocatalytic hydrogen peroxide(H_(2)O_(2))production offers a sustainable route to convert water and oxygen into H_(2)O_(2)using solar energy.However,achieving long-term stability in photocatalysts remains a critica...Photocatalytic hydrogen peroxide(H_(2)O_(2))production offers a sustainable route to convert water and oxygen into H_(2)O_(2)using solar energy.However,achieving long-term stability in photocatalysts remains a critical challenge due to mismatched kinetics between oxygen reduction(ORR)and water oxidation(WOR),which leads to hole accumulation and oxidative degradation.Here,we report a redox-mediated strategy to address this bottleneck by designing a hydroquinone-embedded covalent organic framework(Tz-QH-COF)that enables reversible hole buffering and kinetic balance.The hydroquinone(QH)units act as dynamic hole reservoirs,capturing excess holes during ORR and converting to benzoquinone(Q),which is regenerated to QH via WOR,thereby preventing oxidative decomposition.This reversible QH/Q cycle,directly visualized through in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy,ensures unmatched stability,achieving continuous H_(2)O_(2) production for 528 h(22 d)with an accumulated yield of 18.6 mmol L^(–1)—the highest reported duration for organic photocatalysts.Density functional theory calculations reveal that the QH units exhibit a strong oxygen adsorption energy and favorable two-electron ORR/WOR pathways with low energy barriers.The synergy between experimental and theoretical insights elucidates a redox-mediated charge-balance mechanism,advancing the design of robust photocatalysts for solar-driven H_(2)O_(2) synthesis.展开更多
Genetic disruption of the RAS binding domain(RBD)of Phosphoinositide 3-kinase alpha(PI3Kα)impairs the growth of tumors driven by the small guanosine triphosphatase RAS in mice and does not impact PI3Kα's role in...Genetic disruption of the RAS binding domain(RBD)of Phosphoinositide 3-kinase alpha(PI3Kα)impairs the growth of tumors driven by the small guanosine triphosphatase RAS in mice and does not impact PI3Kα's role in insulin mediated control of glucose homeostasis.Selectively blocking the RAS-PI3Kαinteraction may represent a strategy for treating RAS-dependent cancers as it would avoid the toxicity associated with inhibitors of PI3Kαlipid kinase activity.We developed compounds that bind covalently to cysteine 242 in the RBD of PI3K p110αand block RAS activation of PI3Kαactivity.In mice,inhibitors slow the growth of RAS mutant tumors and Human Epidermal Growth Factor Receptor 2(HER2)overexpressing tumors,particularly when combined with other inhibitors of the RAS/Mitogen-activated protein kinase pathway,without causing hyperglycemia.Oncogenic mutations in the small guanosine triphosphatase RAS occur in 20%of human cancers,with RAS proteins activating both the mitogen-activated protein kinase(MAPK)and Phosphoinositide 3-kinase(PI3K)pathways(1-3).As each of these pathways has oncogenic potential,simultaneous activation,as occurs in mutant RAS driven cancers,generates aggressive disease.In RAS-driven cell and animal models,inhibition of both the MAPK and PI3K pathways is more efficacious than targeting the individual pathways(4);however,dose-limiting toxicities in humans prevent clinical success of this strategy.展开更多
基金the financial support provided by the National Natural Science Foundation of China(Nos.22175094,21971113)。
文摘Covalent organic frameworks(COFs)have great potential as adsorbents due to their customizable functionality,low density and high porosity.However,COFs powder exists with poor processing and recycling performance.Moreover,due to the accumulation of COFs nanoparticles,it is not conducive to the full utilization of their surface functional groups.Currently,the strategy of COFs assembling into aerogel can be a good solution to this problem.Herein,we successfully synthesize composite aerogels(CSR)by in-situ self-assembly of two-dimensional COFs and graphene based on crosslinking of sodium alginate.Sodium alginate in the composite improves the mechanical properties of the aerogel,and graphene provides a template for the in-situ growth of COFs.Impressively,CSR aerogels with different COFs and sizes can be prepared by changing the moiety of the ligand and modulating the addition amount of COFs.The prepared CSR aerogels exhibit porous,low density,good processability and good mechanical properties.Among them,the density of CSR-N-1.6 is only 5 mg/cm3,which is the lowest density among the reported COF aerogels so far.Due to these remarkable properties,CSR aerogels perform excellent adsorption and recycling properties for the efficient and rapid removal of organic pollutants(organic dyes and antibiotics)from polluted water.In addition,it is also possible to visually recognize the presence of antibiotics by fluorescence detection.This work not only provides a new strategy for synthesizing COF aerogels,but also accelerates the practical application of COF aerogels and contributes to environmental remediation.
基金supported by the National Natural Science Foundation of China(No.U2067212)the National Science Fund for Distinguished Young Scholars(No.21925603).
文摘A sp^(2) carbon-conjugated covalent organic framework (BDATN) was modified through γ-ray radiation reduction and subsequent acidification with hydrochloric acid to yield a novel functional COF (named rBDATN-HCl) for Cr(Ⅵ) removal.The morphology and structure of rBDATN-HCl were analyzed and identified by SEM,FTIR,XRD and solid-state13C NMR.It is found that the active functional groups,such as hydroxyl and amide,were introduced into BDATN after radiation reduction and acidification.The prepared rBDATN-HCl demonstrates a photocatalytic reduction removal rate of Cr(Ⅵ) above 99%after 60min of illumination with a solid-liquid ratio of 0.5 mg/mL,showing outstanding performance,which is attributed to the increase of dispersibility and adsorption sites of r BDATN-HCl.In comparison to the cBDATN-HCl synthesized with chemical reduction,rBDATN-HCl exhibits a better photoreduction performance for Cr(Ⅵ),demonstrating the advantages of radiation preparation of rBDATN-HCl.It is expected that more functionalized sp^(2) carbon-conjugated COFs could be obtained by this radiation-induced reduction strategy.
基金financially supported by the National Natural Science Foundation of China(62464010)Spring City Plan-Special Program for Young Talents(K202005007)+3 种基金Yunnan Talents Support Plan for Yong Talents(XDYC-QNRC-2022-0482)Yunnan Local Colleges Applied Basic Research Projects(202101BA070001-138)Key Laboratory of Artificial Microstructures in Yunnan Higher EducationFrontier Research Team of Kunming University 2023。
文摘Zinc-ion batteries(ZIBs)are inexpensive and safe,but side reactions on the Zn anode and Zn dendrite growth hinder their practical applications.In this study,1,3,5-triformylphloroglycerol(Tp)and various diamine monomers(p-phenylenediamine(Pa),benzidine(BD),and 4,4"-diamino-p-terphenyl(DATP))were used to synthesize a series of two-dimensional covalent-organic frameworks(COFs).The resulting COFs were named TpPa,TpBD,and TpDATP,respectively,and they showed uniform zincophilic sites,different pore sizes,and high Young's moduli on the Zn anode.Among them,TpPa and TpBD showed lower surface work functions and higher ion transfer numbers,which were conducive to uniform galvanizing/stripping zinc and inhibited dendrite growth.Theoretical calculations showed that TpPa and TpBD had wider negative potential region and greater adsorption capacity for Zn2+than TpDATP,providing more electron donor sites to coordinate with Zn^(2+).Symmetric cells protected by TpPa and TpBD stably cycled for more than 2300 h,whereas TpDATP@Zn and the bare zinc symmetric cells failed after around 150 and200 h.The full cells containing TpPa and TpBD modification layers also showed excellent cycling capacity at 1 A/g.This study provides comprehensive insights into the construction of highly reversible Zn anodes via COF modification layers for advanced rechargeable ZIBs.
基金supported by the National Natural Science Foundation of China(Nos.22375031,22202037,22472023)the Fundamental Research Funds for the Central Universities(Nos.2412023YQ001,2412023QD019,2412024QD014)+1 种基金supported by grants from the seventh batch of Jilin Province Youth Science and Technology Talent Lifting Project(No.QT202305)Science and Technology Development Plan Project of Jilin Province,China(No.20240101192JC)。
文摘The light-driven CO_(2)reduction reaction(CO_(2)RR)to CO is a very effective way to address global warming.To avoid competition with water photolysis,metal-free gas-solid CO_(2)RR catalysts should be investigated.Covalent organic frameworks(COFs)offer a promising approach for CO_(2)transformation but lack high efficiency and selectivity in the absence of metals.Here,we have incorporated a pyridine nitrogen component into the imine-COF conjugated structure(Tp Pym).This innovative system has set a record of producing a CO yield of 1565μmol g^(-1)within 6 h.The soft X-ray absorption fine structure measurement proves that Tp Pym has both better conjugation and electron cloud enrichment.The electronic structure distribution delays the charge-carrier recombination,as evidenced by femtosecond transient absorption spectroscopy.The energy band diagram and theoretical calculation show that the conduction-band potential of Tp Pym is lower and the reduction reaction of CO_(2)to CO is more likely to occur.
基金financially supported by the Natural Science Foundation of Shandong Province(No.ZR2022MB034)。
文摘The advancement of functional adhesives featuring recyclable and repairable properties is of great significance in interfacial science and engineering.Herein,a series of high-strength,recyclable fluorine-containing adhesives(ESOx-FPF)were designed and synthesized by crosslinking two prepolymers,FPF-B(derived from side-chain fluorinated diol,isocyanate,and aminoboric acid)and ESO-B(synthesized from biobased epoxy soybean oil and aminoboric acid),through dynamic boro-oxygen bonds.The resulting adhesive exhibited an optimal tensile strength of 42 MPa and the shear strength on steel plates reached as high as 3.89 MPa.More importantly,benefiting from the dynamic reversibility of the boron-oxygen bonds along with the hydrogen bonds interaction,ESOx-FPF can be welded with the assistance of solvents and recycled for multiple cycles.The outstanding healing efficiency and excellent reprocessability of these functional adhesives were confirmed by mechanical testing.Moreover,the as-prepared adhesives demonstrated universal and remarkable adhesion to various substrates,such as aromatic polyamide,aluminum plates and polycarbonate,meanwhile,they could be easily disassembled and recycled using ethanol without damaging the substrates surface.This study not only provides a simple strategy for the synthesis of eco-friendly adhesives with weldable and recyclable properties,but also sheds light on the development of other functional materials utilizing dynamic covalent chemistry.
基金supported by the Beijing Natural Science Foundation(No.Z230021)the National Natural Science Foundation of China(No.52202356)+1 种基金the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(No.2021-RC350-001)the CAMS Innovation Fund for Medical Sciences(No.2022-I2M-1-013).
文摘The cyclic guanosine monophosphate-adenosine monophosphate synthase and the stimulator of interferon genes(cGAS-STING)has emerged as a promising target for cancer immunotherapy.However,the development of natural STING agonists is impeded by several challenges,including limited biostability,poor pharmacokinetics,and inefficient cytosolic delivery.Herein,we meticulously designed a doublelayer polyethylenimine(PEI)modified nanoscale covalent organic polymer(CPGP)for efficient delivery of 23cyclic guanosine monophosphate-adenosine monophosphate(cGAMP),a natural STING agonist.The double-layer PEI structured CPGP enhanced both the loading capacity and stability of cGAMP.Furthermore,CPGP improved the intracellular delivery efficiency and amplified the activation of STING pathway for the secretion of type-I interferon and pro-inflammatory cytokines.In contrast,single-layered nanoparticles failed to permit stable loading and intracellular delivery of cGAMP for immune response.The nano-STING agonist also mitigated the immunosuppressive tumor microenvironment(TME)by reducing regulatory T cells and polarizing M2 macrophages to the M1 phenotype,thereby creating an immune-supportive TME to enhance adaptive immune responses.The combination of CPGP and immune checkpoint blockers showed synergistic effect,further enhancing the inhibition effect on tumor growth.This double-layer PEI modified CPGP may offer a generalizable platform for other natural dinucleotide STING agonists to overcome the cascade delivery barriers,augmenting immune activation for tumor immunotherapy.
基金the financial support by the National Natural Science Foundation of China(Nos.22205124,52172206)Natural Science Foundation of Shandong province(Nos.ZR2021QB070,ZR2023QB110)+2 种基金Basic Research Projects for the Pilot Project of Integrating Science and Education and Industry of Qilu University of Technology(Shandong Academy of Sciences)(Nos.2023PY024,2023PX108)Special Fund for Taishan Scholars Projectthe Development Plan of Youth Innovation Team in Colleges and Universities of Shandong Province。
文摘The high conductivity of electrocatalyst can eliminate the Schottky energy barrier at the interface of heterogeneous phases during an electrocatalytic reaction and accelerate the rapid electron transfer to the catalytic active center.Therefore,the electronic conductivity is a vital parameter for oxygen reduction reaction(ORR).Covalent triazine frameworks(CTFs)have shown great potential application as electrocatalysts in ORR with a merit of the diverse building blocks.However,the intrinsic low conductivity and high impedance of CTFs could be significant setbacks in electrocatalytic application.Herein,CTFs were constructed by introducing F and N co-modification for efficient 2e^(-)ORR.Compared with the pristine CTF,the co-presence of F,N could increase the conductivity obviously by 1000-fold.As a result,F-N-CTF exhibits enhanced catalytic performance of H_(2)O_(2)generation and selectivity towards reaction pathways.This work reveals the importance of conductivity optimization for CTFs and provides guidance for designing high conductivity non-metallic organic semiconductor catalysts for 2e^(-)ORR.
基金financially supported by the National Key Research and Development Program of China(2022YFB3806500)the National Natural Science Foundation of China(22273100)+1 种基金Dalian-Institute of Chemical Physics(DICPI202440 and DICP I202218)Dalian-Science and Technology-Innovation Fund(2023JJ12GX023)。
文摘Flexible covalent organic framework(COF)film has drawn much attention as a promising functional material due to their unique molecular structure and self-supporting property.However,the traditional solvothermal method of synthesizing flexible COF film is usually complicated,long-term duration and energy-consuming,making it unsuitable for scalable preparation.To address these limitations,a new method combining electrospinning and sacrificial template is proposed to quickly produce triazinebased COF fiber films at room temperature.The method is easy to operate and has a short reaction time(minimum 0.5 h)without dehydration and deoxygenation processes at room temperature,making it suitable for large-scale production(20 cm×30 cm).Different from the unprocessable of COF powder,COF films not only have good flexibility and mechanical properties,but also can be patterned with multiple functions to adapt to various application scenarios.Moreover,the functionality of triazine-structured COF is retained,enabling the use of the films in energy conversion and storage applications.Triazine-based COFs naturally have scalable conjugated structure,thus showing potential photocatalytic probability.Furthermore,the large pore structure of COF films enables loading of phase change materials endowing comprehensive properties of thermal management and flame retardance.This study proposes a strategy for the rapid synthesis of COF fiber films at room temperature and paves the way for multifunctional and high-performance COF based materials.
基金supported by the National Key R&D Program of China (Nos. 2022YFC3500800 and 2022YFC3500805)。
文摘Prostaglandin E2(PGE2) serves as the ultimate mediator of fever induced by infiammatory factors. In contrast to cyclooxygenase inhibitors that suppress arachidonic acid metabolism, antipyretic herbs possess a well-established clinical history in effectively managing fever. However, the specific mechanisms underlying their efficacy remain unclear. Following the screening for lead compounds that inhibit PGE2from antipyretic herbs, alkynylated active molecule probes were designed and synthesized to track and identify potential targets. The target investigation revealed that three antipyretic compounds, namely cinnamaldehyde, 2,4-decadienal, and perillaldehyde, containing α,β-unsaturated aldehyde groups irreversibly targeted the microsomal PGES1-TM4 helix(m PGES1-TM4) at Ser139. This specific interaction effectually inhibited PGE2 production in the cerebral vasculature, leading to exert potent antipyretic effects.α,β-Unsaturated aldehydes targeting m PGES1-TM4 offer a new approach for antipyretic effects with significant potential for various applications.
基金supported by the Project of Key R&D Program of Shandong Province(2023CXGC010712).Geoffrey I.N.
文摘In this work,a novel electrochemical sensor based on covalent organic framework@carbon black@molecularly imprinted polydopamine(COF@CB@MPDA)was developed for selective recognition and determination of ciprofloxacin(CF).COF@CB@MPDA possessed good water dispersibility and was synthesized by the selfpolymerization of dopamine under alkaline conditions in the presence of the COF,CB and CF.The high surface area COF enhanced the adsorption of CF,whilst CB gave the composites high electrical conductivity to improve the sensitivity of the proposed COF@CB@MPDA/glassy carbon electrode(GCE)sensor.The specific recognition of CF by COF@CB@MPDA involved hydrogen bonding and van der Waals interactions.Under optimized conditions,the sensor showed a good linear relationship with CF concentration over the range of 5.0×10^(–7)and 1.0×10^(–4)mol/L,with a limit of detection(LOD)of 9.53×10^(–8)mol/L.Further,the developed sensor exhibited high selectivity,repeatability and stability for CF detection in milk and milk powders.The method used to fabricate the COF@CB@MPDA/GCE sensor could be easily adapted for the selective recognition and detection of other antibacterial agents and organic pollutants in the environment.
基金Financial support from the Natural Science Foundation(NSF) of China(Nos.22205015,22175020,and 22235001)the National Postdoctoral Program for Innovative Talents(No.BX20220032)+1 种基金the China Postdoctoral Science Foundation Funded Project(No.2022BG013)the Fundamental Research Funds for the Central Universities(Nos.00007709 and 00007770)。
文摘Dimensionality has great influence on the photo/electro-catalysts properties of covalent organic frameworks(COFs) because of the different electronic and porous structures.However,very rare attention has been paid on the dimensionality and function correlations of COF materials.In the present work,one new two-dimensional phthalocyanine COF,namely 2D-NiPc-COF,and one new three-dimensional phthalocyanine COF,namely 3D-NiPc-COF,were fabricated according to the imide reaction between tetraanhydrides of 2,3,9,10,16,17,23,24-octacarboxyphthalocyaninato nickel(Ⅱ) with [2,2-bipyridine]-5,5-diamine and tetrakis(4-aminophenyl) methane,respectively.The crystalline structures of both COFs are verified by the powder X-ray diffraction analysis,computational simulation,and high resolution transmission electron microscopy measurement.Notably,3D-NiPc-COF with dispersed conjugated modules has high utilization efficiency of NiPc electroactive sites of 26.8%,almost two times higher than the in-plane stacking2D-NiPc-COF measured by electrochemical measurement,in turn resulting in its superior electrocatalytic performance with high CO_(2)-to-CO Faradaic efficiency over 90% in a wide potential window,a large partial CO current density of-13.97 mA/cm^(2) at-0.9 V(vs.reversible hydrogen electrode) to 2D-NiPc-COF.Moreover,3D-NiPc-COF has higher turnover number and turnover frequency of 5741.6 and 0.18 s^(-1) at-0.8 V during 8 h lasting measurement.The present work provides an example for the investigation on the correlation between dimensionality and electrochemical properties of 2D and 3D phthalocyanine COFs.
基金supported by the National Natural Science Foundation of China(Grant Nos.22271164 and U20A20259 and 22371147)the Fundamental Research Funds for the Central Universities,the NCC Fund(Grant No.NCC2020FH04)+1 种基金the Tianshan Innovation Team Plan of Xinjiang Uygur Autonomous Region(Grant No.2023D14002)Nankai University(NKU).
文摘Covalent organic cages(COCs)are three-dimensional organic molecules with permanent cavities,known for their ordered pore structures,excellent processability,and modular design.They have shown significant potential in applications such as gas adsorption,molecular separation,and catalysis.Introducing chiral elements into COCs results in chiral COCs with confined chiral cavities,which endows them with unique chiral functions and expands their application prospects.This review summarizes the research progress on chiral covalent organic cages,focusing on strategies for incorporating chiral elements,the structures and synthesis methods of representative chiral COCs,and advancements in their chiral functions.Additionally,we provide perspectives on future research directions.We hope this review will inspire further interest and creativity among researchers in the field of chiral molecular cages,leading to the development of materials with unique structures and functions.
基金financially supported by the National Natural Science Foundation of China(No.52203136)Heilongjiang Provincial Natural Science Foundation for Excellent Youth Fund(No.YQ2024E007)+4 种基金Natural Science Foundation of Heilongjiang Province(No.LH2022E015)the China Postdoctoral Science Foundation(No.2024MD753912)Heilongjiang Postdoctoral Fund(No.LBH-Z24107)Northeast Petroleum University Cultivation Foundation for‘National fund’(No.2023GPL-04)Northeast Petroleum University Scientic Research Foundation for Advanced Talents(Nos.2021KQ05,2019KQ85)
文摘Slippery liquid-infused porous surfaces(SLIPS)with exceptional liquid repellency and extremely low sliding angles demonstrate significant potential for applications in anti-corrosion,anti-fouling,and anti-scaling.However,the poor stability of the oil layer restricts its practical applications.Herein,a durable SLIPS coating with highly stable oil layer was developed by combining hierarchical porous structures with covalent interpenetrating networks and multiple interfacial interactions.The hierarchical porous structure was constructed via urea thermal decomposition with in situ hybridization of SiO_(2)and embedded carbon nanotubes(CNTs).Furthermore,the oil layer was chemically immobilized on the coating surface using methylenediphenyl diisocyanate(MDI)as a molecular bridge,leveraging interfacial covalent bonding andπ-OH interactions,which significantly enhanced its anti-corrosion properties,with an initial|Z|_(0.01 Hz)of1.22×10^(8)Ωcm^(2).Dynamic scaling experiments revealed a 96.47%improvement in scaling inhibition efficiency compared to conventional superhydrophobic coatings,showing its excellent anti-scaling properties.Owing to the durability and liquidity of oi layer,the prepared FEVE-SiO_(2)/CNTs@MDI SLIPS coating maintained outstanding slippery performance(water sliding angle<10°)even after 14 days of underwater immersion.Additionally,the coating also exhibited excellent thermal stability(120°C),remarkable shear resistance(5000 rpm),and ultraviolet resistance performance.Therefore,the prepared FEVE-SiO_(2)/CNTs@MDI SLIPS coating has broad practical application prospects in the field of industrial oilfield pipeline protection.
基金supported by the National Nat-ural Science Foundation of China(22465012)the Key Research and Development Project of Hainan Province,China(ZDYF2024GXJS005)the Major Science and Technology Plan of Hainan Province,China(ZDKJ202016).
文摘Porous materials are excellent adsorbents for the removal of organic dyes from sewage and play a significant role in environmental restoration.Herein,two ferrocene(Fc)-based covalent organic frameworks(Fc-COFs),namely FcTF-COF and FcBD-COF,are successfully synthesized for the first time through a solvothermal method,and the obtained Fc-COFs powders are used to adsorb Congo red(CR)from water.The results show that both FcTF-COF and FcBD-COF have superb adsorption performance towards CR with ultrahigh adsorption capability of 1672.2 mg g−1 and 1983.7 mg g−1 at pH=4.0,respectively,outperforming the majority of the reported solid porous adsorbents.The maximum adsorption of both Fc-COFs agrees with the Sips adsorption isothermal model,indicating that their adsorption was dominated by heterogeneous adsorption.The Coulombic interactions,hydrogen bonding,π-πinteractions and ion-dipolar interactions should all contribute to their ultrahigh CR adsorption capability and high-pH resistance performance regardless of the pH in the range of 4-9.In addition,after five cycles,both COFs still remain their exceptional high CR adsorption capabilities.This study offers a prospective organic porous adsorbent with promising applications for organic dye removal in sewage processing.
基金supported by the National Natural Science Foundation of China(22171136,52202138)the Natural Science Foundation of Jiangsu Province(BK20200472,BK20220079)+3 种基金the Medical Innovation and Development Project of Lanzhou University(lzuyxcx-2022-156)CAMS Innovation Fund for Medical Sciences(CIFMS,2019-I2M-5-074,2021-I2M-1-026,2021-I2M-3-001)the Frontier Technologies R&D Program of Jiangsu(Grant no.BF2024033)G.Z.acknowledges the support of the Thousand Young Talent Plan.
文摘Noteworthy challenges such as severe side reactions,interfacial instability,and dendrite growth have plagued rechargeable alkali metal batteries for a long time.Alleviating the plight necessitates innovative membranes capable of modulating ion transport and establishing stable interfaces.The exploration of implemented membranes with thermal/mechanical and electrochemical stability is crucial for achieving high-performance and safe alkali metal batteries.Crystalline covalent organic framework(COF)membranes have emerged as promising materials for next-generation energy storage systems due to their tunable porosity and exceptional physicochemical properties.This review specifically examines the critical role of COF membranes in enabling sustainable alkali metal(Li/Na/K)batteries,with a particular focus on design principles,performance advantages,and key challenges of COF membranes.The discussion emphasizes structure-property relationships specifically relevant to rechargeable battery applications,supported by recent decades of research.Impressively,this mini review further identifies three critical research frontiers:reticular chemistry-guided materials design,multifunctional composite architectures,and in-situ characterization techniques.This targeted analysis provides actionable insights for developing COF membranes that address the fundamental limitations of current alkali metal battery technologies.
基金supported by the National Natural Science Foundation of China(22172055)the Science Fund for Distinguished Young Scholars of Guangdong Province(2023B1515040026)+1 种基金the Key Area Research and Development Program of Guangdong Province(2023B0101200008)the Natural Science Foundation of Guangdong Province(2022A1515011892).
文摘Stimuli-responsive two-dimensional (2D) covalent organic frameworks (COFs) with precise structures and permanent porosity have been employed as platforms for sensors. The slight change of backbones inside frameworks leads to different electronic states by external stimuli, such as solvent, pH, and water. Herein, we introduced an alkynyl-based building block (ETBA) with high planarity to synthesize two imine-based alkynyl-COFs (ETBA-TAPE-COF and ETBA-PYTA-COF) with high yield, good crystallinity, and chemical stability. Due to the presence of acetylene bonds, ETBA-TAPE-COF does not adopt the completely overlapping AA stacking mode. Slight interlayer displacement occurs along the parallel direction relative to the acetylene linkages, which facilitates lower configurational energy. Additionally, the introduction of pyrene group contributes to high π-electron mobility of ETBA-PYTA-COF. The interactions between electron-withdrawing group (ETBA) and electron-donating group (PYTA) during the processes of protonation and intramolecular charge transfer (ICT) endow ETBA-PYTA-COF with excellent acidochromic and solvatochromic properties, respectively. Based on this, a fluorescence sensor is successfully established, which can be used for rapid response to trace amounts of water in organic solvents. In contrast, ETBA-TAPE-COF does not exhibit these photophysical properties due to its higher HOMO–LUMO gap compared to ETBA-PYTA-COF. This work proposes a new strategy for designing and preparing COFs with unique photophysical properties without introducing additional functional groups.
基金financially supported by the National Natural Science Foundation of China(Nos.22322801,22108010,22278124)Fundamental Research Funds for the Central Universities(No.buctrc202135)。
文摘Covalent organic frameworks(COFs),as a burgeoning class of crystalline porous materials have attracted widespread interest due to their designable structures and customized functions.However,the solvothermal synthesis of COFs is often time-consuming and conducted at a high temperature within a sealed vessel,and also requires a large amount of poisonous solvents,which is generally not available for scaling-up production and commercial application.In recent years,great efforts have been made to explore simple,green,and efficient approaches for COFs synthesis.In this comprehensive review,we summarized the advances in emergent strategies by highlighting their distinct features.Fundamental issues and future directions are also discussed with the object of bringing implications for large-scale and sustainable fabrication of COFs.
基金supported by the National Natural Science Foundation of China(No.51972066)the Natural Science Foundation of Guangdong Province of China(No.2024A1515012499)。
文摘The uneven deposition and high reactivity of lithium-metal anode(LMA)lead to uncontrollable dendrite growth,low Coulombic efficiency,and safety concerns,hindering their commercialization.Here,a representative polar-rich-group triazine-based covalent organic framework(COF-TzDha)with a desolvation effect is designed as an interlayer for stable,dendrite-free LMA.The abundant triazine rings in COFTzDha as a donor effectively attract lithium ions,while the one-dimensional nanopore structure facilitates lithium-ion migration.The periodic arrangement of polar groups(-OH)in the backbone interacts with electrolyte components(DOL,DME,TFSI-)to form a hydrogen bonding network that slows solvent molecules transport.Therefore,COF-TzDha effectively desolvates lithium ions from the solvent sheath,promoting uniform lithium ion flux and Li plating/stripping.Theoretical calculations verify that COFTzDha with abundant adsorption sites and strong adsorption energy facilitates lithium ion desolvation.Consequently,the introduction of COF-TzDha obtains a high ion mobility(0.75).The Li|COF@PP|Li symmetric cell cycles stably for over 1200 h at 4 mA cm^(-2)/4.0 mA h cm^(-2).The Li|COF@PP|LiFePO_(4)full cell also displays highly stable cycling performance with 600 cycles(75.5%capacity retention,~100% Coulombic efficiency)at 1 C.This work verifies an effective strategy for inducing uniform Li deposition and achieving dendrite-free,stable LMA using a polar-rich-group COF interlayer with a desolvation effect.
文摘Photocatalytic hydrogen peroxide(H_(2)O_(2))production offers a sustainable route to convert water and oxygen into H_(2)O_(2)using solar energy.However,achieving long-term stability in photocatalysts remains a critical challenge due to mismatched kinetics between oxygen reduction(ORR)and water oxidation(WOR),which leads to hole accumulation and oxidative degradation.Here,we report a redox-mediated strategy to address this bottleneck by designing a hydroquinone-embedded covalent organic framework(Tz-QH-COF)that enables reversible hole buffering and kinetic balance.The hydroquinone(QH)units act as dynamic hole reservoirs,capturing excess holes during ORR and converting to benzoquinone(Q),which is regenerated to QH via WOR,thereby preventing oxidative decomposition.This reversible QH/Q cycle,directly visualized through in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy,ensures unmatched stability,achieving continuous H_(2)O_(2) production for 528 h(22 d)with an accumulated yield of 18.6 mmol L^(–1)—the highest reported duration for organic photocatalysts.Density functional theory calculations reveal that the QH units exhibit a strong oxygen adsorption energy and favorable two-electron ORR/WOR pathways with low energy barriers.The synergy between experimental and theoretical insights elucidates a redox-mediated charge-balance mechanism,advancing the design of robust photocatalysts for solar-driven H_(2)O_(2) synthesis.
文摘Genetic disruption of the RAS binding domain(RBD)of Phosphoinositide 3-kinase alpha(PI3Kα)impairs the growth of tumors driven by the small guanosine triphosphatase RAS in mice and does not impact PI3Kα's role in insulin mediated control of glucose homeostasis.Selectively blocking the RAS-PI3Kαinteraction may represent a strategy for treating RAS-dependent cancers as it would avoid the toxicity associated with inhibitors of PI3Kαlipid kinase activity.We developed compounds that bind covalently to cysteine 242 in the RBD of PI3K p110αand block RAS activation of PI3Kαactivity.In mice,inhibitors slow the growth of RAS mutant tumors and Human Epidermal Growth Factor Receptor 2(HER2)overexpressing tumors,particularly when combined with other inhibitors of the RAS/Mitogen-activated protein kinase pathway,without causing hyperglycemia.Oncogenic mutations in the small guanosine triphosphatase RAS occur in 20%of human cancers,with RAS proteins activating both the mitogen-activated protein kinase(MAPK)and Phosphoinositide 3-kinase(PI3K)pathways(1-3).As each of these pathways has oncogenic potential,simultaneous activation,as occurs in mutant RAS driven cancers,generates aggressive disease.In RAS-driven cell and animal models,inhibition of both the MAPK and PI3K pathways is more efficacious than targeting the individual pathways(4);however,dose-limiting toxicities in humans prevent clinical success of this strategy.
