Pervaporation(PV),as an environmental friendly and energy-saving separation technology,has been received increasing attention in recent years.This article reviews the preparation and application of macroporous ceramic...Pervaporation(PV),as an environmental friendly and energy-saving separation technology,has been received increasing attention in recent years.This article reviews the preparation and application of macroporous ceramic-supported polymer composite pervaporation membranes.The separation materials of polymer/ceramic composite membranes presented here include hydrophobic polydimethylsiloxane(PDMS) and hydrophilic poly(vinyl alcohol)(PVA),chitosan(CS) and polyelectrolytes.The effects of ceramic support treatment,polymer solution properties,interfacial adhesion and incorporating or blending modification on the membrane structure and PV performance are discussed.Two in-situ characterization methods developed for polymer/ceramic composite membranes are also covered in the discussion.The applications of these composite membranes in pervaporation process are summarized as well,which contain the bio-fuels recovery,gasoline desulfuration and PV coupled proc-ess using PDMS/ceramic composite membrane,and dehydration of alcohols and esters using ceramic-supported PVA or PVA-CS composite membrane.Finally,a brief conclusion remark on polymer/ceramic composite mem-branes is given and possible future research is outlined.展开更多
To meet the evolving demands of aeroengine development,the structural and performance requirements for ceramic cores have become increasingly stringent.Vat photopolymerization 3D printing,owing to its moldless,fiexibl...To meet the evolving demands of aeroengine development,the structural and performance requirements for ceramic cores have become increasingly stringent.Vat photopolymerization 3D printing,owing to its moldless,fiexible manufacturing,and other advantages,demonstrates significant potential in the preparation of ceramic cores with intricate structures.However,its practical application still faces multiple challenges,including layered structures and property anisotropy,defects such as cracks and collapse during printing and sintering,forming inaccuracies,and difficulties in controlling surface roughness.Recent advances have focused on optimizing slurry formulation and rheology,improving curing behavior,introducing auxiliary powders and additives,tailoring forming parameters,and optimizing the sintering process.Nevertheless,effectively suppressing lamellar defects,achieving superior dimensional accuracy,and maintaining high surface quality in complex structures remain the core scientific and technical issues to be solved.Future research should concentrate on refining curing mechanisms,advancing powder design and organic system optimization,and regulating the coupled processes of forming,debinding,and sintering to accelerate the application of VPP 3D printed ceramic cores in aerospace manufacturing.展开更多
Ceramic cores are important in the fabrication of superalloy hollow blades,which are increasingly characterized by intricate internal cavity channels.This complexity poses significant challenges to traditional manufac...Ceramic cores are important in the fabrication of superalloy hollow blades,which are increasingly characterized by intricate internal cavity channels.This complexity poses significant challenges to traditional manufacturing processes.The vat photopolymerization 3D printing technology provides a new choice for ceramic cores with complex structures.However,the lamellar structure of the vat photopolymerization 3D printed ceramic cores leads to the anisotropy.Meanwhile,the low strength and high shrinkage of ceramic cores restrict their industrial application.In this study,using Al_(2)O_(3)powder as the main material,the effects of zircon content on the sintering shrinkage,open porosity,fiexural strength,and other properties of Al_(2)O_(3)-based ceramic cores were studied to address the aforementioned issues.The influencing mechanism of zircon distribution on sintering shrinkage was analyzed,and the strengthening mechanism of mullite on ceramic cores was discussed from both thermodynamics and dynamics aspects.Through the comprehensive evaluation of ceramic core properties,the Al_(2)O_(3)-based ceramic core with 15vol.%zircon exhibites the optimal performance.Compared with the core samples without zirconium addition,the fiexural strength of the Al_(2)O_(3)-based ceramic core with 15vol.%zircon increases from 14.80 MPa to 61.54 MPa at 25°C,an increase of 315.8%;and from 4.91 MPa to 11.59 MPa at 1,500°C,an increase of 136.0%.The shrinkage in the Z-axis is reduced by 21%,which better weakens the anisotropy of the shrinkage of 3D printed Al_(2)O_(3)-based ceramic cores.ZrO_(2)phase and mullite phase are formed by zircon,which improve the comprehensive properties of Al_(2)O_(3)-based ceramic cores.The successful 3D printing of high-performance Al_(2)O_(3)-based ceramic cores via vat photopolymerization has promoted its industrial application for fabricating ceramic cores with complex structures.展开更多
Vat photopolymerization(VPP)3D printing is an optimized technology for complex-shaped ceramic cores,in which the solid loading of ceramic slurries greatly infiuences the microstructure and property of the final cerami...Vat photopolymerization(VPP)3D printing is an optimized technology for complex-shaped ceramic cores,in which the solid loading of ceramic slurries greatly infiuences the microstructure and property of the final ceramic parts.However,the high solid loading of slurries is highly limited by the high viscosity.In this study,silica-based ceramic core slurries with solid loading up to 68vol.%were achieved by the composition design to optimize the performance,considering the curing,rheological,and double bond conversion rate.The slurries demonstrate superior curing and rheological performance with mass ratio of monomers being 3:2 and mass fraction of BYK111 being 4wt.%.Afterwards,the impact of solid loading on the morphology and mechanical properties was investigated.As the solid loading increases,the microstructure becomes gradually dense,leading to an improved flexural strength of 19.5 MPa.Additionally,the sintering shrinkage becomes more uniform,satisfying the casting requirements effectively.This work serves as a guide for the preparation of ceramic slurries with a high solid loading.展开更多
The complex ceramic core used for hollow turbine blades requires a high porosity and a high fiexural strength. For a better balance between porosity and fiexural strength, ceramic materials with porous structures are ...The complex ceramic core used for hollow turbine blades requires a high porosity and a high fiexural strength. For a better balance between porosity and fiexural strength, ceramic materials with porous structures are preferred. In order to achieve the transition from disordered pore formation to ordered pore formation, Al_(2)O_(3) ceramic cores with triply periodic minimal surface(TPMS) micro lattice structures with different structural configurations(gyroid, diamond, and neovius) and different volume fractions of lattice structures(30, 40, and 50, vol.%) were designed and prepared by vat photopolymerization 3D printing. The effects of structural configuration and volume fraction of the lattice structure on the following structural shrinkage, microstructure, and flexural strength were investigated. The shrinkage relationship of the three lattice configurations is: neovius>diamond>gyroid. Besides, it is found that with an increase in the volume fraction of the 3D printed Al_(2)O_(3) ceramic micro lattice structures, their fiexural strength correspondingly increases ranging from 54.95 MPa to 139.1 MPa. The maximum average fiexural strength of the 3D printed Al_(2)O_(3) ceramic micro lattice structures is obtained when the structural configuration is diamond and with a volume fraction of 50vol.%, which is 139.1 MPa. Even when the volume fraction of the lattice structure is 30vol.%, that is to say the porosity is 70%, the fiexural strength is as high as 50-70 MPa, which can still be maintained at a high level. In addition, when the volume fraction of the lattice structure is a certain value, the sample with diamond configuration has a higher strength. The internal pore morphology, pore size, and porosity of the cores are precisely controlled, achieving both a high porosity and a high strength. Therefore, this study maintains high porosity and high strength simultaneously, providing a new lattice structure design idea for 3D printed ceramic cores.展开更多
Under solvothermal conditions,1,4‑naphthalenedicarboxylic acid(H_(2)ndc)and 9,9′‑dihexyl‑2,7‑di(pyridin‑4‑yl)fluorene(hfdp)reacted with Co^(2+)ions and Cd^(2+)ions to form two coordination polymers,[Co(hfdp)(ndc)(H2O...Under solvothermal conditions,1,4‑naphthalenedicarboxylic acid(H_(2)ndc)and 9,9′‑dihexyl‑2,7‑di(pyridin‑4‑yl)fluorene(hfdp)reacted with Co^(2+)ions and Cd^(2+)ions to form two coordination polymers,[Co(hfdp)(ndc)(H2O)]·DMA}n(1)and{[Cd(hfdp)(ndc)(H_(2)O)]·DMA}_(n)(2),respectively(DMA=N,N‑dimethylacetamide).Single‑crystal X‑ray diffraction analyses showed that both complexes 1 and 2 contain similar structures.Topological analysis indicates that complexes 1 and 2 have a{44·62}planar structure.In addition,both complexes reveal good thermal stability and fluorescence sensing performance.They exhibited good sensitivity and selectivity towards 2,4,6‑trinitrophenol(TNP)by fluorescent quenching.The limits of detection of 1 and 2 for TNP were 0.107 and 0.327μmol·L^(-1),respectively.CCDC:2475515,1;2475516,2.展开更多
Unmanned combat aerial vehicles require lightweight,stealth-capable exhaust systems.However,traditional metallic nozzles increase radar detectability and reduce range,while advanced composites offer high performance b...Unmanned combat aerial vehicles require lightweight,stealth-capable exhaust systems.However,traditional metallic nozzles increase radar detectability and reduce range,while advanced composites offer high performance but are expensive.Therefore,to improve the operational range and survivability of unmanned combat aerial vehicles,a lightweight,high-temperature-resistant,oxidation-resistant,and low-observable composite exhaust nozzle is developed to replace conventional metallic straight-type nozzles.The nozzle features a double serpentine shape to reduce radar and infrared signatures and is manufactured as a monolithic structure using the filament winding process,accommodating the complex geometry and large size(length:1.8 m,width:0.8 m).The exhaust nozzle consists of a ceramic matrix composite made of silicon carbide fibers and a silicon oxycarbide matrix,which absorbs and scatters radio frequency signals while withstanding prolonged exposure to high-temperature(700℃)oxidizing environments typical of engine exhaust gases.The polysiloxane resin used to produce the silicon oxycarbide matrix poses significant challenges owing to its low tackiness and high viscosity variations depending on the presence of nanoparticles,making filament winding difficult.These challenges are addressed by optimizing resin viscosity and winding pattern design.As a result,the tensile strength of the composite specimens fabricated with the optimized viscosity increases by 228.03% before pyrolysis and 97.68%after pyrolysis,compared with that of the non-optimized specimens.In addition,the density and tensile strength of the composite processed via three cycles of polymer infiltration and pyrolysis increased by 13.08% and 80.37%,respectively,compared to those of the non-densified composite.High-temperature oxidation and flame tests demonstrate exceptional thermal and oxidative stability.Furthermore,when compared with carbon fiber-reinforced ceramic matrix composites,the developed composite exhibits a permittivity at least two levels lower and a reflection loss below7 dB within the frequency range of 9.3-10.9 GHz,underscoring its superior electromagnetic stealth performance.展开更多
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam...Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering.展开更多
Polymer-modified bentonite(PMB)is much more effective at containing chemically aggressive liquids than conventional bentonite.The PMB manufacturing process typically utilizes natural,high-quality sodium bentonite(NaB)...Polymer-modified bentonite(PMB)is much more effective at containing chemically aggressive liquids than conventional bentonite.The PMB manufacturing process typically utilizes natural,high-quality sodium bentonite(NaB)owing to its excellent hydrophilicity and swelling capacity.However,calcium bentonite(CaB),which is much more abundant worldwide,is rarely used for containment applications owing to its poor hydrophilicity.This study proposed a polymerization method that transforms sodium-activated calcium bentonite(NCB)into PMB to achieve low hydraulic conductivity(k)to aggressive liquids.The mechanism for its low k was revealed through characterization techniques and analyses(e.g.X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy(SEM),and Brunauer-Emmett-Teller(BET)).The results showed that the PMB had a small amount of polymer elution(indicating better interface stability)and thus exhibited excellent barrier properties under chemically aggressive conditions,with the k of<10^(-11) m/s for 0.6 mol/L NaCl solution,which is four orders of magnitude lower than that of the NCB(k=3×10^(-7) m/s).Various microscopic analyses indicated that the selected monomers were successfully polymerized,and intercalated into and grafted onto the montmorillonite layers of bentonite.The formed polymer network increased the swelling capability of PMB granules,decreased the pore size,and created narrow and tortuous flow pathways leading to a very low k to aggressive liquids.展开更多
Liver is a vital organ in the human body and plays a central role in the metabolism and detoxification of endotoxins and exotoxins.Bilirubin is an endotoxin derived from hemoglobin(Hb).Removing excess bilirubin in the...Liver is a vital organ in the human body and plays a central role in the metabolism and detoxification of endotoxins and exotoxins.Bilirubin is an endotoxin derived from hemoglobin(Hb).Removing excess bilirubin in the blood is crucial for the treatment of liver diseases.Hemoperfusion,which relies on adsorbents to efficiently adsorb toxins,is a widely applied procedure for the removal of blood toxins.To broaden and improve the range and performance of hemoperfusion adsorbents,we synthesized cationic hyper crosslinked polymers(HCPs)with strong affinity for bilirubin.This material exhibited outstanding adsorption performance,with a maximum adsorption capacity of 934 mg/g and a removal efficiency of 96%.Further investigation confirmed their excellent selectivity,reusability,and biocompatibility.These findings expand the potential applications of HCPs and provide insight into strategies for constructing promising hemoperfusion adsorbent materials.展开更多
With the global push for energy conservation and the rapid development of low-power,flexible and wearable optical displays,the demand for electrochromic technology has surged.Gel polymer electrolytes(GPEs),a crucial c...With the global push for energy conservation and the rapid development of low-power,flexible and wearable optical displays,the demand for electrochromic technology has surged.Gel polymer electrolytes(GPEs),a crucial component of electrochromic devices(ECDs),show great promise in applications.This is attributed to their efficient ion-transport capabilities,excellent mechanical properties and strong adhesion.All of these characteristics are conducive to enhancing the safety of the devices,streamlining the packaging process,significantly improving the electrochromic performance of ECDs and boosting their commercial application potential.This review provides a comprehensive overview of GPEs for ECDs,focusing on their basic designs,functional modifications and practical applications.Firstly,this review outlines the fundamental design of GPEs for ECDs,encompassing key performance index,classification,gelation mechanism and preparation methods.Building on this foundation,it provides an in-depth discussion of functionalized GPEs developed to enhance device performance or expand functionality,including electrochromic,temperature-responsive,photo-responsive and stretchable self-healing GPE.Furthermore,the integration of GPEs into various ECD applications,including smart windows,displays,energy storage devices and wearable electronic,are summarized to highlight the advantages that the design of GPEs brings to the practical application of ECDs.Finally,based on the summary of GPEs employed for ECDs,the challenges and development expectations in this direction were indicated.展开更多
Organic pollutants,a pivotal factor in water pollution,have persistently menaced the aquatic ecosystem,as well as the sustainable development of human health,economy,and society.Consequently,there is an urgent need fo...Organic pollutants,a pivotal factor in water pollution,have persistently menaced the aquatic ecosystem,as well as the sustainable development of human health,economy,and society.Consequently,there is an urgent need for advanced techniques to efficiently eliminate organic micropollutants from water.Here,we present the synthesis of three nonporous cavitand-crosslinked polymers capable of adsorbing diverse organic pollutants from aqueous solutions.These polymeric adsorbents exhibit outstanding adsorptive performance towards the tested micropollutants,characterized by high apparent adsorption rate constants(kobs)and maximum adsorption capacities(qmax,e).Notably,Compound NCCP-1 demonstrated a remarkable qmax,e of 459 mg/g for bisphenol A(BPA),ranking among the highest values reported for organic polymer adsorbents.In-depth investigation of the adsorption mechanism of the nonporous polymer revealed that it involves the recognition of pollutants by the deep cavities of the cavitand moieties and the interstitial spaces between them,primarily mediated by the hydrophobic effect.Furthermore,NCCP-1 was applied in situ water purification simulations and was proven to maintain its removal efficiency over more than four cycles,highlighting its potential for practical applications in water treatment.展开更多
Succinonitrile(SN)-based polymer plastic crystal electrolytes(PPCEs)are regarded as promising candidates for lithium metal batteries but suffer from serious side reactions with Li metal.Herein,we propose a multi-dimen...Succinonitrile(SN)-based polymer plastic crystal electrolytes(PPCEs)are regarded as promising candidates for lithium metal batteries but suffer from serious side reactions with Li metal.Herein,we propose a multi-dimensional optimization strategy to alleviate the side reactions between SN and Li metal,and develop a highly stable poly-vinylethylene carbonate-based PPCE(PPCE-VEC).Moreover,we identify the intrinsic factors of multi-dimensional polymer structures on the electrolyte stability by three typical classes of polyesters.The PPCE-VEC constructed by in situ polymerization exhibits much better stability than poly-vinylene carbonate-based PPCE(PPCE-VCA)and poly-trifluoroethyl acrylate-based PPCE(PPCE-TFA),which is verified by its fewer SN-decomposition species in X-ray photoelectron spectroscopy(XPS)and outstanding full cell performance.The PPCE-VEC-enabled LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)full cell achieve 73.7%capacity retention after 1400 cycles,which outperforms PPCE-VCA-and PPCE-TFA-enabled full cells(61.9%and 46.9%).Spectral analysis and theoretical calculation reveal that the high solvation ability of the carbonyl site,flexible polymer chain,and homogeneous electrolyte phase of PPCE-VEC are favorable to maximizing competition coordination with Li^(+)to weaken the Li^(+)–SN binding and shape an anion-rich solvation structure.This optimized polymer-involved Li^(+)solvation enhances SN stability and facilitates the formation of B/F enriched solid-electrolyte interphase(SEI),thus significantly improving PPCE stability.展开更多
Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2...Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2)O(1)was synthesized as a 2D structure using Coas the metal source,methanol‑water(4∶6,V/V)as the solvent,and specific concentrations of 2,5‑furandicarboxylic acid(H_(2)FDCA)and 1,3,5‑triimidazole benzene(L).Adjusting to pure water and lowering the concentration of L yielded the 1D chain structure of[Co(HL)2(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(2).Using Cu(Ⅱ)as the metal source,methanol/water(9∶1,V/V)as the solvent,and specific concentrations of L and H2FDCA,the 1D chain structure of[Cu(L)(FDCA)(H_(2)O)]·2H_(2)O(3)was synthesized.Upon increasing the concentrations of L and H2FDCA,and switching the solvent to pure water,the 1D chain structure of[Cu(HL)_(2)(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(4)was obtained.This shows that changing the solvent and ligand concentrations can affect the structural changes of CPs.In addition,the solid‑state photoluminescence of CPs 1‑4 at room temperature was studied,and their morphological changes were observed via scanning electron microscopy.Density functional theory calculations revealed that the negative charge concentrates on the O and N atoms of the ligand,facilitating ligand‑metal ion coordination.CCDC:2403934,1;2403935,2;2403936,3;2403938,4.展开更多
To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polym...To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polymer light-emitting diodes(PLEDs).Herein,we introduced the steric carbazole-fluorene nanogrid into light-emitting diphenyl sulfone-based p-n polymer semiconductors(PG and PDG) via metal-free C-N coupling polymerization for the fabrication of deep-blue PLEDs.The steric,rigid and twisted configuration between nanogrid and diphenyl sulfone in PG and PDG present the unique characteristic of large steric hindrance interaction to suppress interchain aggregation in solid state.Due to the different length of electron-deficient diphenyl sulfone monomers,PG showed a deep-blue emission with a maximum peak at 428 nm but red-shifted to 480 nm for the PDG films.Interestingly,similar deep-blue emission behavior of PG in diluted non-polar solution and films suggested the extremely weak interchain aggregation.Finally,PLEDs based on PG are fabricated with a stable deep-blue emission of CIE(0.15,0.10),and corresponding EL spectral profile is also completely identical to PL ones of diluted solution,revealed the intrachain emission without obvious interchain excited state,confirmed effectiveness of the steric hindrance functionalization of nanogrid in p-n polymer semiconductor for deep-blue light-emitting organic optoelectronics.展开更多
Ceramic aerogels(CAs)have emerged as a significant research frontier across various applications due to their lightweight,high porosity,and easily tunable structural characteristics.However,the intrinsic weak interact...Ceramic aerogels(CAs)have emerged as a significant research frontier across various applications due to their lightweight,high porosity,and easily tunable structural characteristics.However,the intrinsic weak interactions among the constituent nanoparticles,coupled with the limited toughness of traditional CAs,make them susceptible to structural collapse or even catastrophic failure when exposed to complex mechanical external forces.Unlike 0D building units,1D ceramic nanofibers(CNFs)possess a high aspect ratio and exceptional flexibility simultaneously,which are desirable building blocks for elastic CAs.This review presents the recent progress in electrospun ceramic nanofibrous aerogels(ECNFAs)that are constructed using ECNFs as building blocks,focusing on the various preparation methods and corresponding structural characteristics,strategies for optimizing mechanical performance,and a wide range of applications.The methods for preparing ECNFs and ECNFAs with diverse structures were initially explored,followed by the implementation of optimization strategies for enhancing ECNFAs,emphasizing the improvement of reinforcing the ECNFs,establishing the bonding effects between ECNFs,and designing the aggregate structures of the aerogels.Moreover,the applications of ECNFAs across various fields are also discussed.Finally,it highlights the existing challenges and potential opportunities for ECNFAs to achieve superior properties and realize promising prospects.展开更多
Thermoelectric(TE)materials,being capable of converting waste heat into electricity,are pivotal for sustainable energy solutions.Among emerging TE materials,organic TE materials,particularly conjugated polymers,are ga...Thermoelectric(TE)materials,being capable of converting waste heat into electricity,are pivotal for sustainable energy solutions.Among emerging TE materials,organic TE materials,particularly conjugated polymers,are gaining prominence due to their unique combination of mechanical flexibility,environmental compatibility,and solution-processable fabrication.A notable candidate in this field is poly(2,5-bis(3-alkylthiophen-2-yl)thieno[3,2-b]thiophene)(PBTTT),a liquid-crystalline conjugated polymer,with high charge carrier mobility and adaptability to melt-processing techniques.Recent advancements have propelled PBTTT’s figure of merit from below 0.1 to a remarkable 1.28 at 368 K,showcasing its potential for practical applications.This review systematically examines strategies to enhance PBTTT’s TE performance through doping(solution,vapor,and anion exchange doping),composite engineering,and aggregation state controlling.Recent key breakthroughs include ion exchange doping for stable charge modulation,multi-heterojunction architectures reducing thermal conductivity,and proton-coupled electron transfer doping for precise Fermi-level tuning.Despite great progress,challenges still persist in enhancing TE conversion efficiency,balancing or decoupling electrical conductivity,Seebeck coefficient and thermal conductivity,and leveraging melt-processing scalability of PBTTT.By bridging fundamental insights with applied research,this work provides a roadmap for advancing PBTTT-based TE materials toward efficient energy harvesting and wearable electronics.展开更多
Antibiotics,as an emerging pollutant due to their extensive use and difficulty in biodegradation,can cause harm to health through bioaccumulation.To address this,various photocatalysts have been developed for rapid an...Antibiotics,as an emerging pollutant due to their extensive use and difficulty in biodegradation,can cause harm to health through bioaccumulation.To address this,various photocatalysts have been developed for rapid antibiotic removal.However,their low concentrations limit mass transfer efficiency,resulting in suboptimal performance.Adsorption is crucial for enhancing photocatalytic efficiency.In this study,a series of binary heterojunction catalysts(x%BWO@STHP)were synthesized,consisting of Bi_(2)WO_(6)(BWO)grafted with sulfonated triptycene-based hypercrosslinked polymer(STHP).The high specific surface area of STHP,combined withπ-πconjugation and ionic interactions with antibiotics,significantly enhances adsorption capacity.This facilitates effective contact between low-concentration pollutants in aqueous solutions and the active sites of the catalyst.The formation of a Z-scheme heterojunction between BWO and STHP facilitates photogenerated charge separation,and further significantly improves photocatalytic degradation performance.Specifically,the 20%BWO@STHP catalyst achieved rapid adsorption equilibrium for oxytetracycline(OTC),doxycycline(DOX),and tetracycline(TC)within 2 min and completely degraded them after 15 min of irradiation.Compared to pristine BWO,the photocatalytic reaction rate constants are significantly increased,being 9.69 times higher for OTC and 13.45 times higher for DOX.The catalyst exhibits excellent reusability and holds promising potential for practical applications.展开更多
Ceramic thin plates were prepared using kaolin,potassium sodium feldspar and quartz powder as the main raw materials and kaolin,α-Al_(2)O_(3),MoO_(3) and AlF_(3)·3H_(2)O as additives.The experiment examined the ...Ceramic thin plates were prepared using kaolin,potassium sodium feldspar and quartz powder as the main raw materials and kaolin,α-Al_(2)O_(3),MoO_(3) and AlF_(3)·3H_(2)O as additives.The experiment examined the effects of different additives on mullite formation,as well as the microstructure and properties of the ceramic thin plates.Additionally,the study explored the toughening and strengthening mechanisms induced by the additives,providing a theoretical foundation for further optimizing the toughness of ceramic thin plates.The results showed that the D4 sample fired at 1220℃(with an addition of 20 wt% α-Al_(2)O_(3))exhibited the best performance,with a water absorption rate of 0.07%,apparent porosity of 0.18%,bulk density of 2.75 g·cm^(-3),firing shrinkage of 12.76%,bending strength reaching 101.93 MPa,and fracture toughness of 2.51 MPa·m^(1/2).As the amount ofα-Al_(2)O_(3) additive increased,the ceramic thin plates exhibited a greater abundance of short rod-like mullite and corundum grains,which were tightly packed together,forming a framework for the ceramic thin plates.This microstructure enhanced pathways for crack propagation,dispersed internal stresses,and increased fracture surface energy,resulting in significant improvements in both strength and fracture toughness of the ceramic thin plates.展开更多
(NbZrHfTi)C high-entropy ceramics,as an emerging class of ultra-high-temperature materials,have garnered significant interest due to their unique multi-principal-element crystal structure and exceptional hightemperatu...(NbZrHfTi)C high-entropy ceramics,as an emerging class of ultra-high-temperature materials,have garnered significant interest due to their unique multi-principal-element crystal structure and exceptional hightemperature properties.This study systematically investigates the mechanical properties of(NbZrHfTi)C high-entropy ceramics by employing first-principles density functional theory,combined with the Debye-Grüneisen model,to explore the variations in their thermophysical properties with temperature(0–2000 K)and pressure(0–30 GPa).Thermodynamically,the calculated mixing enthalpy and Gibbs free energy confirm the feasibility of forming a stable single-phase solid solution in(NbZrHfTi)C.The calculated results of the elastic stiffness constant indicate that the material meets the mechanical stability criteria of the cubic crystal system,further confirming the structural stability.Through evaluation of key mechanical parameters—bulk modulus,shear modulus,Young’s modulus,and Poisson’s ratio—we provide comprehensive insight into the macro-mechanical behaviour of the material and its correlation with the underlying microstructure.Notably,compared to traditional binary carbides and their average properties,(NbZrHfTi)C exhibits higher Vickers hardness(Approximately 28.5 GPa)and fracture toughness(Approximately 3.4 MPa⋅m^(1/2)),which can be primarily attributed to the lattice distortion and solid-solution strengthening mechanism.The study also utilizes the quasi-harmonic approximation method to predict the material’s thermophysical properties,including Debye temperature(initial value around 563 K),thermal expansion coefficient(approximately 8.9×10^(−6) K−1 at 2000 K),and other key parameters such as heat capacity at constant volume.The results show that within the studied pressure and temperature ranges,(NbZrHfTi)C consistently maintains a stable phase structure and good thermomechanical properties.The thermal expansion coefficient increasing with temperature,while heat capacity approaches the Dulong-Petit limit at elevated temperatures.These findings underscore the potential of(NbZrHfTi)C applications in ultra-high temperature thermal protection systems,cutting tool coatings,and nuclear structural materials.展开更多
文摘Pervaporation(PV),as an environmental friendly and energy-saving separation technology,has been received increasing attention in recent years.This article reviews the preparation and application of macroporous ceramic-supported polymer composite pervaporation membranes.The separation materials of polymer/ceramic composite membranes presented here include hydrophobic polydimethylsiloxane(PDMS) and hydrophilic poly(vinyl alcohol)(PVA),chitosan(CS) and polyelectrolytes.The effects of ceramic support treatment,polymer solution properties,interfacial adhesion and incorporating or blending modification on the membrane structure and PV performance are discussed.Two in-situ characterization methods developed for polymer/ceramic composite membranes are also covered in the discussion.The applications of these composite membranes in pervaporation process are summarized as well,which contain the bio-fuels recovery,gasoline desulfuration and PV coupled proc-ess using PDMS/ceramic composite membrane,and dehydration of alcohols and esters using ceramic-supported PVA or PVA-CS composite membrane.Finally,a brief conclusion remark on polymer/ceramic composite mem-branes is given and possible future research is outlined.
基金supported by the National Key R&D Program of China(Grant Nos.2024YFB3714502,2024YFB3714501,2024YFB3714504)the National Natural Science Foundation of China(Grant Nos.52130204,52174376)+5 种基金the TQ Innovation Foundation(Grant No.23-TQ09-02-ZT-01-005)the Aeronautical Science Foundation of China(Grant No.20220042053001)the Ningbo Science and Technology Plan Project(Grant No.2025Z070)the Key R&D Project of Shaanxi Province(Grant Nos2024GX-YBXM-220,2024CY-GJHX-29,2024GX-ZDCYL-03-03,2024GX-YBXM-400)the National Advanced Rare Metal Materials Innovation Center Project[Grant No.2024 ZG-GCZX-01(1)-01]the Foundation of China Scholarship Council(Grant No.202406290136)。
文摘To meet the evolving demands of aeroengine development,the structural and performance requirements for ceramic cores have become increasingly stringent.Vat photopolymerization 3D printing,owing to its moldless,fiexible manufacturing,and other advantages,demonstrates significant potential in the preparation of ceramic cores with intricate structures.However,its practical application still faces multiple challenges,including layered structures and property anisotropy,defects such as cracks and collapse during printing and sintering,forming inaccuracies,and difficulties in controlling surface roughness.Recent advances have focused on optimizing slurry formulation and rheology,improving curing behavior,introducing auxiliary powders and additives,tailoring forming parameters,and optimizing the sintering process.Nevertheless,effectively suppressing lamellar defects,achieving superior dimensional accuracy,and maintaining high surface quality in complex structures remain the core scientific and technical issues to be solved.Future research should concentrate on refining curing mechanisms,advancing powder design and organic system optimization,and regulating the coupled processes of forming,debinding,and sintering to accelerate the application of VPP 3D printed ceramic cores in aerospace manufacturing.
基金financially supported by the National Natural Science Foundation of China(Nos.52402094,U234120139,and U22A20129)the National Defense Basic Scientific Research Program of China(No.JCKY2022130C005)+8 种基金the China Postdoctoral Science Foundation(No.2023M743571)the Postdoctoral Fellowship Program of CPSF(N o.GZC20232743)the Innovation Project of IMR(2024-PY11)the Open Research Fund of National Key Laboratory of Advanced Casting Technologies(No.CAT2023-006)the Graduate Education Quality Engineering Project of Anhui Province(No.2023cxcysj015)the Science and Technology Plan Project of Liaoning Province(No.2024JH2/101900011)the Nationa Key Research and Development Program of China(Nos2024YFB3714500 and 2018YFB1106600)the China United Gas Turbine Technology Co.Ltd.under the project of J790。
文摘Ceramic cores are important in the fabrication of superalloy hollow blades,which are increasingly characterized by intricate internal cavity channels.This complexity poses significant challenges to traditional manufacturing processes.The vat photopolymerization 3D printing technology provides a new choice for ceramic cores with complex structures.However,the lamellar structure of the vat photopolymerization 3D printed ceramic cores leads to the anisotropy.Meanwhile,the low strength and high shrinkage of ceramic cores restrict their industrial application.In this study,using Al_(2)O_(3)powder as the main material,the effects of zircon content on the sintering shrinkage,open porosity,fiexural strength,and other properties of Al_(2)O_(3)-based ceramic cores were studied to address the aforementioned issues.The influencing mechanism of zircon distribution on sintering shrinkage was analyzed,and the strengthening mechanism of mullite on ceramic cores was discussed from both thermodynamics and dynamics aspects.Through the comprehensive evaluation of ceramic core properties,the Al_(2)O_(3)-based ceramic core with 15vol.%zircon exhibites the optimal performance.Compared with the core samples without zirconium addition,the fiexural strength of the Al_(2)O_(3)-based ceramic core with 15vol.%zircon increases from 14.80 MPa to 61.54 MPa at 25°C,an increase of 315.8%;and from 4.91 MPa to 11.59 MPa at 1,500°C,an increase of 136.0%.The shrinkage in the Z-axis is reduced by 21%,which better weakens the anisotropy of the shrinkage of 3D printed Al_(2)O_(3)-based ceramic cores.ZrO_(2)phase and mullite phase are formed by zircon,which improve the comprehensive properties of Al_(2)O_(3)-based ceramic cores.The successful 3D printing of high-performance Al_(2)O_(3)-based ceramic cores via vat photopolymerization has promoted its industrial application for fabricating ceramic cores with complex structures.
基金financially supported by the National Natural Science Foundation of China(No.52102062)the Xi’an Science and Technology Plan Project(No.23LLRH0004)the Key Research and Development Project of Shaanxi Province of China(2024GX-YBXM-352)。
文摘Vat photopolymerization(VPP)3D printing is an optimized technology for complex-shaped ceramic cores,in which the solid loading of ceramic slurries greatly infiuences the microstructure and property of the final ceramic parts.However,the high solid loading of slurries is highly limited by the high viscosity.In this study,silica-based ceramic core slurries with solid loading up to 68vol.%were achieved by the composition design to optimize the performance,considering the curing,rheological,and double bond conversion rate.The slurries demonstrate superior curing and rheological performance with mass ratio of monomers being 3:2 and mass fraction of BYK111 being 4wt.%.Afterwards,the impact of solid loading on the morphology and mechanical properties was investigated.As the solid loading increases,the microstructure becomes gradually dense,leading to an improved flexural strength of 19.5 MPa.Additionally,the sintering shrinkage becomes more uniform,satisfying the casting requirements effectively.This work serves as a guide for the preparation of ceramic slurries with a high solid loading.
基金supported by the National Natural Science Foundation of China (Grant No. 52275310)。
文摘The complex ceramic core used for hollow turbine blades requires a high porosity and a high fiexural strength. For a better balance between porosity and fiexural strength, ceramic materials with porous structures are preferred. In order to achieve the transition from disordered pore formation to ordered pore formation, Al_(2)O_(3) ceramic cores with triply periodic minimal surface(TPMS) micro lattice structures with different structural configurations(gyroid, diamond, and neovius) and different volume fractions of lattice structures(30, 40, and 50, vol.%) were designed and prepared by vat photopolymerization 3D printing. The effects of structural configuration and volume fraction of the lattice structure on the following structural shrinkage, microstructure, and flexural strength were investigated. The shrinkage relationship of the three lattice configurations is: neovius>diamond>gyroid. Besides, it is found that with an increase in the volume fraction of the 3D printed Al_(2)O_(3) ceramic micro lattice structures, their fiexural strength correspondingly increases ranging from 54.95 MPa to 139.1 MPa. The maximum average fiexural strength of the 3D printed Al_(2)O_(3) ceramic micro lattice structures is obtained when the structural configuration is diamond and with a volume fraction of 50vol.%, which is 139.1 MPa. Even when the volume fraction of the lattice structure is 30vol.%, that is to say the porosity is 70%, the fiexural strength is as high as 50-70 MPa, which can still be maintained at a high level. In addition, when the volume fraction of the lattice structure is a certain value, the sample with diamond configuration has a higher strength. The internal pore morphology, pore size, and porosity of the cores are precisely controlled, achieving both a high porosity and a high strength. Therefore, this study maintains high porosity and high strength simultaneously, providing a new lattice structure design idea for 3D printed ceramic cores.
文摘Under solvothermal conditions,1,4‑naphthalenedicarboxylic acid(H_(2)ndc)and 9,9′‑dihexyl‑2,7‑di(pyridin‑4‑yl)fluorene(hfdp)reacted with Co^(2+)ions and Cd^(2+)ions to form two coordination polymers,[Co(hfdp)(ndc)(H2O)]·DMA}n(1)and{[Cd(hfdp)(ndc)(H_(2)O)]·DMA}_(n)(2),respectively(DMA=N,N‑dimethylacetamide).Single‑crystal X‑ray diffraction analyses showed that both complexes 1 and 2 contain similar structures.Topological analysis indicates that complexes 1 and 2 have a{44·62}planar structure.In addition,both complexes reveal good thermal stability and fluorescence sensing performance.They exhibited good sensitivity and selectivity towards 2,4,6‑trinitrophenol(TNP)by fluorescent quenching.The limits of detection of 1 and 2 for TNP were 0.107 and 0.327μmol·L^(-1),respectively.CCDC:2475515,1;2475516,2.
基金supported by the Agency for Defense Development Grant Funded by the Korean Government(Grant No.912822501).
文摘Unmanned combat aerial vehicles require lightweight,stealth-capable exhaust systems.However,traditional metallic nozzles increase radar detectability and reduce range,while advanced composites offer high performance but are expensive.Therefore,to improve the operational range and survivability of unmanned combat aerial vehicles,a lightweight,high-temperature-resistant,oxidation-resistant,and low-observable composite exhaust nozzle is developed to replace conventional metallic straight-type nozzles.The nozzle features a double serpentine shape to reduce radar and infrared signatures and is manufactured as a monolithic structure using the filament winding process,accommodating the complex geometry and large size(length:1.8 m,width:0.8 m).The exhaust nozzle consists of a ceramic matrix composite made of silicon carbide fibers and a silicon oxycarbide matrix,which absorbs and scatters radio frequency signals while withstanding prolonged exposure to high-temperature(700℃)oxidizing environments typical of engine exhaust gases.The polysiloxane resin used to produce the silicon oxycarbide matrix poses significant challenges owing to its low tackiness and high viscosity variations depending on the presence of nanoparticles,making filament winding difficult.These challenges are addressed by optimizing resin viscosity and winding pattern design.As a result,the tensile strength of the composite specimens fabricated with the optimized viscosity increases by 228.03% before pyrolysis and 97.68%after pyrolysis,compared with that of the non-optimized specimens.In addition,the density and tensile strength of the composite processed via three cycles of polymer infiltration and pyrolysis increased by 13.08% and 80.37%,respectively,compared to those of the non-densified composite.High-temperature oxidation and flame tests demonstrate exceptional thermal and oxidative stability.Furthermore,when compared with carbon fiber-reinforced ceramic matrix composites,the developed composite exhibits a permittivity at least two levels lower and a reflection loss below7 dB within the frequency range of 9.3-10.9 GHz,underscoring its superior electromagnetic stealth performance.
基金Supported by the National Natural Science Foundation of China(Nos.52293472,22473096 and 22471164)。
文摘Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering.
基金supported by the National Natural Science Foundation of China(Grant Nos.52478351,52208329)the Shenzhen Science and Technology Innovation Commission(Grant No.JCYJ20240813143306009)support is gratefully acknowledged.
文摘Polymer-modified bentonite(PMB)is much more effective at containing chemically aggressive liquids than conventional bentonite.The PMB manufacturing process typically utilizes natural,high-quality sodium bentonite(NaB)owing to its excellent hydrophilicity and swelling capacity.However,calcium bentonite(CaB),which is much more abundant worldwide,is rarely used for containment applications owing to its poor hydrophilicity.This study proposed a polymerization method that transforms sodium-activated calcium bentonite(NCB)into PMB to achieve low hydraulic conductivity(k)to aggressive liquids.The mechanism for its low k was revealed through characterization techniques and analyses(e.g.X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy(SEM),and Brunauer-Emmett-Teller(BET)).The results showed that the PMB had a small amount of polymer elution(indicating better interface stability)and thus exhibited excellent barrier properties under chemically aggressive conditions,with the k of<10^(-11) m/s for 0.6 mol/L NaCl solution,which is four orders of magnitude lower than that of the NCB(k=3×10^(-7) m/s).Various microscopic analyses indicated that the selected monomers were successfully polymerized,and intercalated into and grafted onto the montmorillonite layers of bentonite.The formed polymer network increased the swelling capability of PMB granules,decreased the pore size,and created narrow and tortuous flow pathways leading to a very low k to aggressive liquids.
基金financially supported by the International Cooperation Program of the Ministry of Science and Technology of Hubei Province(No.2023EHA069)Shenzhen Science and Technology Program(No.JCYJ20230807143702005)the National Foreign Experts Program(No.G2022027015L)。
文摘Liver is a vital organ in the human body and plays a central role in the metabolism and detoxification of endotoxins and exotoxins.Bilirubin is an endotoxin derived from hemoglobin(Hb).Removing excess bilirubin in the blood is crucial for the treatment of liver diseases.Hemoperfusion,which relies on adsorbents to efficiently adsorb toxins,is a widely applied procedure for the removal of blood toxins.To broaden and improve the range and performance of hemoperfusion adsorbents,we synthesized cationic hyper crosslinked polymers(HCPs)with strong affinity for bilirubin.This material exhibited outstanding adsorption performance,with a maximum adsorption capacity of 934 mg/g and a removal efficiency of 96%.Further investigation confirmed their excellent selectivity,reusability,and biocompatibility.These findings expand the potential applications of HCPs and provide insight into strategies for constructing promising hemoperfusion adsorbent materials.
基金supported by the National Natural Science Foundation of China(52103299)。
文摘With the global push for energy conservation and the rapid development of low-power,flexible and wearable optical displays,the demand for electrochromic technology has surged.Gel polymer electrolytes(GPEs),a crucial component of electrochromic devices(ECDs),show great promise in applications.This is attributed to their efficient ion-transport capabilities,excellent mechanical properties and strong adhesion.All of these characteristics are conducive to enhancing the safety of the devices,streamlining the packaging process,significantly improving the electrochromic performance of ECDs and boosting their commercial application potential.This review provides a comprehensive overview of GPEs for ECDs,focusing on their basic designs,functional modifications and practical applications.Firstly,this review outlines the fundamental design of GPEs for ECDs,encompassing key performance index,classification,gelation mechanism and preparation methods.Building on this foundation,it provides an in-depth discussion of functionalized GPEs developed to enhance device performance or expand functionality,including electrochromic,temperature-responsive,photo-responsive and stretchable self-healing GPE.Furthermore,the integration of GPEs into various ECD applications,including smart windows,displays,energy storage devices and wearable electronic,are summarized to highlight the advantages that the design of GPEs brings to the practical application of ECDs.Finally,based on the summary of GPEs employed for ECDs,the challenges and development expectations in this direction were indicated.
基金supported by the National Natural Science Foundation of China(Nos.22322107,22101169 and 22071144)by Shanghai Scientific and Technological Committee(No.22010500300).
文摘Organic pollutants,a pivotal factor in water pollution,have persistently menaced the aquatic ecosystem,as well as the sustainable development of human health,economy,and society.Consequently,there is an urgent need for advanced techniques to efficiently eliminate organic micropollutants from water.Here,we present the synthesis of three nonporous cavitand-crosslinked polymers capable of adsorbing diverse organic pollutants from aqueous solutions.These polymeric adsorbents exhibit outstanding adsorptive performance towards the tested micropollutants,characterized by high apparent adsorption rate constants(kobs)and maximum adsorption capacities(qmax,e).Notably,Compound NCCP-1 demonstrated a remarkable qmax,e of 459 mg/g for bisphenol A(BPA),ranking among the highest values reported for organic polymer adsorbents.In-depth investigation of the adsorption mechanism of the nonporous polymer revealed that it involves the recognition of pollutants by the deep cavities of the cavitand moieties and the interstitial spaces between them,primarily mediated by the hydrophobic effect.Furthermore,NCCP-1 was applied in situ water purification simulations and was proven to maintain its removal efficiency over more than four cycles,highlighting its potential for practical applications in water treatment.
基金supported by the National Natural Science Foundation of China(22072048)the Guangdong Provincial Department of Science and Technology(2021A1515010128 and 2022A0505050013).
文摘Succinonitrile(SN)-based polymer plastic crystal electrolytes(PPCEs)are regarded as promising candidates for lithium metal batteries but suffer from serious side reactions with Li metal.Herein,we propose a multi-dimensional optimization strategy to alleviate the side reactions between SN and Li metal,and develop a highly stable poly-vinylethylene carbonate-based PPCE(PPCE-VEC).Moreover,we identify the intrinsic factors of multi-dimensional polymer structures on the electrolyte stability by three typical classes of polyesters.The PPCE-VEC constructed by in situ polymerization exhibits much better stability than poly-vinylene carbonate-based PPCE(PPCE-VCA)and poly-trifluoroethyl acrylate-based PPCE(PPCE-TFA),which is verified by its fewer SN-decomposition species in X-ray photoelectron spectroscopy(XPS)and outstanding full cell performance.The PPCE-VEC-enabled LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)full cell achieve 73.7%capacity retention after 1400 cycles,which outperforms PPCE-VCA-and PPCE-TFA-enabled full cells(61.9%and 46.9%).Spectral analysis and theoretical calculation reveal that the high solvation ability of the carbonyl site,flexible polymer chain,and homogeneous electrolyte phase of PPCE-VEC are favorable to maximizing competition coordination with Li^(+)to weaken the Li^(+)–SN binding and shape an anion-rich solvation structure.This optimized polymer-involved Li^(+)solvation enhances SN stability and facilitates the formation of B/F enriched solid-electrolyte interphase(SEI),thus significantly improving PPCE stability.
文摘Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2)O(1)was synthesized as a 2D structure using Coas the metal source,methanol‑water(4∶6,V/V)as the solvent,and specific concentrations of 2,5‑furandicarboxylic acid(H_(2)FDCA)and 1,3,5‑triimidazole benzene(L).Adjusting to pure water and lowering the concentration of L yielded the 1D chain structure of[Co(HL)2(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(2).Using Cu(Ⅱ)as the metal source,methanol/water(9∶1,V/V)as the solvent,and specific concentrations of L and H2FDCA,the 1D chain structure of[Cu(L)(FDCA)(H_(2)O)]·2H_(2)O(3)was synthesized.Upon increasing the concentrations of L and H2FDCA,and switching the solvent to pure water,the 1D chain structure of[Cu(HL)_(2)(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(4)was obtained.This shows that changing the solvent and ligand concentrations can affect the structural changes of CPs.In addition,the solid‑state photoluminescence of CPs 1‑4 at room temperature was studied,and their morphological changes were observed via scanning electron microscopy.Density functional theory calculations revealed that the negative charge concentrates on the O and N atoms of the ligand,facilitating ligand‑metal ion coordination.CCDC:2403934,1;2403935,2;2403936,3;2403938,4.
基金the support from the Jiangsu Provincial Senior Talent Program (Dengfeng,Jiangsu University)the support from the National Key R&D Program of China (No.2024YFB3612600)+3 种基金the National Natural Science Foundation of China (Nos.22275098,62288102)Basic Research Program of Jiangsu (No.BK20243057)the Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications (No.NY222097)the National Natural Science Foundation of China (No.62205035)。
文摘To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polymer light-emitting diodes(PLEDs).Herein,we introduced the steric carbazole-fluorene nanogrid into light-emitting diphenyl sulfone-based p-n polymer semiconductors(PG and PDG) via metal-free C-N coupling polymerization for the fabrication of deep-blue PLEDs.The steric,rigid and twisted configuration between nanogrid and diphenyl sulfone in PG and PDG present the unique characteristic of large steric hindrance interaction to suppress interchain aggregation in solid state.Due to the different length of electron-deficient diphenyl sulfone monomers,PG showed a deep-blue emission with a maximum peak at 428 nm but red-shifted to 480 nm for the PDG films.Interestingly,similar deep-blue emission behavior of PG in diluted non-polar solution and films suggested the extremely weak interchain aggregation.Finally,PLEDs based on PG are fabricated with a stable deep-blue emission of CIE(0.15,0.10),and corresponding EL spectral profile is also completely identical to PL ones of diluted solution,revealed the intrachain emission without obvious interchain excited state,confirmed effectiveness of the steric hindrance functionalization of nanogrid in p-n polymer semiconductor for deep-blue light-emitting organic optoelectronics.
基金supported by the National Natural Science Foundation of China(Nos.92371110 and 52373281)Weiqiao Science Foundation(H2872302 and H2872303)the Scientific Research Innovation Capability Support Project for Young Faculty.
文摘Ceramic aerogels(CAs)have emerged as a significant research frontier across various applications due to their lightweight,high porosity,and easily tunable structural characteristics.However,the intrinsic weak interactions among the constituent nanoparticles,coupled with the limited toughness of traditional CAs,make them susceptible to structural collapse or even catastrophic failure when exposed to complex mechanical external forces.Unlike 0D building units,1D ceramic nanofibers(CNFs)possess a high aspect ratio and exceptional flexibility simultaneously,which are desirable building blocks for elastic CAs.This review presents the recent progress in electrospun ceramic nanofibrous aerogels(ECNFAs)that are constructed using ECNFs as building blocks,focusing on the various preparation methods and corresponding structural characteristics,strategies for optimizing mechanical performance,and a wide range of applications.The methods for preparing ECNFs and ECNFAs with diverse structures were initially explored,followed by the implementation of optimization strategies for enhancing ECNFAs,emphasizing the improvement of reinforcing the ECNFs,establishing the bonding effects between ECNFs,and designing the aggregate structures of the aerogels.Moreover,the applications of ECNFAs across various fields are also discussed.Finally,it highlights the existing challenges and potential opportunities for ECNFAs to achieve superior properties and realize promising prospects.
基金financial support by Guangdong Basic and Applied Basic Research Foundation(2025A1515012415)National Natural Science Foundation of China(52242305)the Stable Support Project of Shenzhen(Project No.20231122125728001).
文摘Thermoelectric(TE)materials,being capable of converting waste heat into electricity,are pivotal for sustainable energy solutions.Among emerging TE materials,organic TE materials,particularly conjugated polymers,are gaining prominence due to their unique combination of mechanical flexibility,environmental compatibility,and solution-processable fabrication.A notable candidate in this field is poly(2,5-bis(3-alkylthiophen-2-yl)thieno[3,2-b]thiophene)(PBTTT),a liquid-crystalline conjugated polymer,with high charge carrier mobility and adaptability to melt-processing techniques.Recent advancements have propelled PBTTT’s figure of merit from below 0.1 to a remarkable 1.28 at 368 K,showcasing its potential for practical applications.This review systematically examines strategies to enhance PBTTT’s TE performance through doping(solution,vapor,and anion exchange doping),composite engineering,and aggregation state controlling.Recent key breakthroughs include ion exchange doping for stable charge modulation,multi-heterojunction architectures reducing thermal conductivity,and proton-coupled electron transfer doping for precise Fermi-level tuning.Despite great progress,challenges still persist in enhancing TE conversion efficiency,balancing or decoupling electrical conductivity,Seebeck coefficient and thermal conductivity,and leveraging melt-processing scalability of PBTTT.By bridging fundamental insights with applied research,this work provides a roadmap for advancing PBTTT-based TE materials toward efficient energy harvesting and wearable electronics.
基金the financial support provided by the National Natural Science Foundation of China(22478267,22438009,U24A20535)Basic Research Program of Jiangsu province(BK20243002)+1 种基金Prospective Application Research Project of Suzhou(SYC2022042)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Antibiotics,as an emerging pollutant due to their extensive use and difficulty in biodegradation,can cause harm to health through bioaccumulation.To address this,various photocatalysts have been developed for rapid antibiotic removal.However,their low concentrations limit mass transfer efficiency,resulting in suboptimal performance.Adsorption is crucial for enhancing photocatalytic efficiency.In this study,a series of binary heterojunction catalysts(x%BWO@STHP)were synthesized,consisting of Bi_(2)WO_(6)(BWO)grafted with sulfonated triptycene-based hypercrosslinked polymer(STHP).The high specific surface area of STHP,combined withπ-πconjugation and ionic interactions with antibiotics,significantly enhances adsorption capacity.This facilitates effective contact between low-concentration pollutants in aqueous solutions and the active sites of the catalyst.The formation of a Z-scheme heterojunction between BWO and STHP facilitates photogenerated charge separation,and further significantly improves photocatalytic degradation performance.Specifically,the 20%BWO@STHP catalyst achieved rapid adsorption equilibrium for oxytetracycline(OTC),doxycycline(DOX),and tetracycline(TC)within 2 min and completely degraded them after 15 min of irradiation.Compared to pristine BWO,the photocatalytic reaction rate constants are significantly increased,being 9.69 times higher for OTC and 13.45 times higher for DOX.The catalyst exhibits excellent reusability and holds promising potential for practical applications.
基金Funded by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2023YFB4204302)。
文摘Ceramic thin plates were prepared using kaolin,potassium sodium feldspar and quartz powder as the main raw materials and kaolin,α-Al_(2)O_(3),MoO_(3) and AlF_(3)·3H_(2)O as additives.The experiment examined the effects of different additives on mullite formation,as well as the microstructure and properties of the ceramic thin plates.Additionally,the study explored the toughening and strengthening mechanisms induced by the additives,providing a theoretical foundation for further optimizing the toughness of ceramic thin plates.The results showed that the D4 sample fired at 1220℃(with an addition of 20 wt% α-Al_(2)O_(3))exhibited the best performance,with a water absorption rate of 0.07%,apparent porosity of 0.18%,bulk density of 2.75 g·cm^(-3),firing shrinkage of 12.76%,bending strength reaching 101.93 MPa,and fracture toughness of 2.51 MPa·m^(1/2).As the amount ofα-Al_(2)O_(3) additive increased,the ceramic thin plates exhibited a greater abundance of short rod-like mullite and corundum grains,which were tightly packed together,forming a framework for the ceramic thin plates.This microstructure enhanced pathways for crack propagation,dispersed internal stresses,and increased fracture surface energy,resulting in significant improvements in both strength and fracture toughness of the ceramic thin plates.
基金supported by the National Natural Science Foundation of China(Nos.92166105 and 52005053)High-Tech Industry Science and Technology Innovation Leading Program of Hunan Province(No.2020GK2085)the Science and Technology Innovation Program of Hunan Province(No.2021RC3096).
文摘(NbZrHfTi)C high-entropy ceramics,as an emerging class of ultra-high-temperature materials,have garnered significant interest due to their unique multi-principal-element crystal structure and exceptional hightemperature properties.This study systematically investigates the mechanical properties of(NbZrHfTi)C high-entropy ceramics by employing first-principles density functional theory,combined with the Debye-Grüneisen model,to explore the variations in their thermophysical properties with temperature(0–2000 K)and pressure(0–30 GPa).Thermodynamically,the calculated mixing enthalpy and Gibbs free energy confirm the feasibility of forming a stable single-phase solid solution in(NbZrHfTi)C.The calculated results of the elastic stiffness constant indicate that the material meets the mechanical stability criteria of the cubic crystal system,further confirming the structural stability.Through evaluation of key mechanical parameters—bulk modulus,shear modulus,Young’s modulus,and Poisson’s ratio—we provide comprehensive insight into the macro-mechanical behaviour of the material and its correlation with the underlying microstructure.Notably,compared to traditional binary carbides and their average properties,(NbZrHfTi)C exhibits higher Vickers hardness(Approximately 28.5 GPa)and fracture toughness(Approximately 3.4 MPa⋅m^(1/2)),which can be primarily attributed to the lattice distortion and solid-solution strengthening mechanism.The study also utilizes the quasi-harmonic approximation method to predict the material’s thermophysical properties,including Debye temperature(initial value around 563 K),thermal expansion coefficient(approximately 8.9×10^(−6) K−1 at 2000 K),and other key parameters such as heat capacity at constant volume.The results show that within the studied pressure and temperature ranges,(NbZrHfTi)C consistently maintains a stable phase structure and good thermomechanical properties.The thermal expansion coefficient increasing with temperature,while heat capacity approaches the Dulong-Petit limit at elevated temperatures.These findings underscore the potential of(NbZrHfTi)C applications in ultra-high temperature thermal protection systems,cutting tool coatings,and nuclear structural materials.
