Spherical polyelectrolyte brushes (SPBs) consisting of polystyrene (PS) core and poly(2-aminoethyl methacrylate hydrochloride) (PAEMH) shell were prepared by photo-emulsion polymerization. Au nanoparticles (A...Spherical polyelectrolyte brushes (SPBs) consisting of polystyrene (PS) core and poly(2-aminoethyl methacrylate hydrochloride) (PAEMH) shell were prepared by photo-emulsion polymerization. Au nanoparticles (Au-NPs) with controlled size and size distribution were synthesized in situ using SPBs as nanoreactors. Via layer-by-layer deposition technique on the surface of SPBs, nano-composite particles with Au/Ag-NPs bilayer and Au/Ag/Au-NPs trilayer were prepared. The structures of the as-prepared Au/Ag multilayer SPBs were characterized by UV-Vis spectroscopy, TEM, ICP-AES and DLS. The charge reversal of the nano-composite particles observed by zeta potential confirmed the success of layer-by-layer assembly. The Au/Ag-NPs bilayer nano-composite particles showed high catalytic efficiency with an apparent activation energy of about 41.2 kJ/mol in the reduction reaction of 4-nitrophenol to 4-aminophenol in the existence of sodium borohydride monitored. The catalytic activity ofAu/Ag-NPs multilayer SPBs close to that of Au-NPs SPBs and much higher than that of Ag-NPs SPBs reveals its potential applications in cost-effective catalysts with high-performance.展开更多
Orthopedic implants for the treatment of bone defects from various causes have been challenged by insufficient osseointegration,bacterial infection,oxidative stress,immune rejection,and insufficient individualized tre...Orthopedic implants for the treatment of bone defects from various causes have been challenged by insufficient osseointegration,bacterial infection,oxidative stress,immune rejection,and insufficient individualized treatment.These challenges not only impact treatment outcomes but also severely impact patients’daily lives.Layer-by-Layer(LbL)serves as a simple surface coating technique,in simple terms,to functionalize implants by sequentially adsorbing oppositely charged materials onto a substrate.In orthopaedics,LbL self-assembly technology solves some of the challenges by loading various drugs or biological agents on the implant surface and controlling their release precisely to the site of bone defects in a personalized way.This review will introduce the basic principle and the development of LbL in orthopaedics,review and analyze the chemical strategy of LbL in the preparation of bone implants to ensure the stability of the implant,and introduce the use of LbL bone implants in orthopaedics in recent years.The application of LbL includes the realization of programmed drug delivery and sustained release,thereby promoting osseointegration and the formation of new blood vessels,antibacterial,antioxidant,etc.This review focuses on the LbL technology,involving the technology selection for the preparation of bone implants,the chemical strategies of the stability guarantee of LbL implants,the pharmacological properties,loading and release mechanisms of loaded drugs,and the molecular mechanisms of osteogenesis and angiogenesis.The aim of this review is to provide an overview of current research advances,and a prospect in this field was also described.展开更多
The abuse of plastic food packaging has brought about severe white pollution issues around the world.Developing green and sustainable biomass packaging is an effective way to solve this problem.Hence,a chitosan/sodium...The abuse of plastic food packaging has brought about severe white pollution issues around the world.Developing green and sustainable biomass packaging is an effective way to solve this problem.Hence,a chitosan/sodium alginate-based multilayer film is fabricated via a layer-by-layer(LBL)self-assembly method.With the help of superior interaction between the layers,the multilayer film possesses excellent mechanical properties(with a tensile strength of 50 MPa).Besides,the film displays outstanding water retention property(blocking moisture of 97.56%)and ultraviolet blocking property.Anthocyanin is introduced into the film to detect the food quality since it is one natural plant polyphenol that is sensitive to the pH changes ranging from 1 to 13 in food when spoilage occurs.It is noted that the film is also bacteriostatic which is desired for food packaging.This study describes a simple technique for the development of advanced multifunctional and fully biodegradable food packaging film and it is a sustainable alternative to plastic packaging.展开更多
A film with“brick-and-mortar”structure was prepared by layer-by-layer(LBL)technique using polyvinyl alcohol(PVA)and polymethyl methacrylate(PMMA)as the flexible material or“mortar”and mica as the rigid material or...A film with“brick-and-mortar”structure was prepared by layer-by-layer(LBL)technique using polyvinyl alcohol(PVA)and polymethyl methacrylate(PMMA)as the flexible material or“mortar”and mica as the rigid material or“brick”.The film deposited on a glass slide after self-assembly cycles had a thickness of 3μm thick and an uneven,wavy surface.The film exhibits enhanced mechanical properties,i e,the hardness and indentation modulus values could reach 6.14 and 68.41 GPa,respectively.The hardness and elastic toughness were found to be depended on three factors,i e,the ratio of PVA to mica,the number of self-assembly cycles,and the pretreatment method of the mica suspension.The self-assembly process was driven by formation of the hydrogen bonds between the silanol groups of mica and the hydroxyl groups of PVA and carbonyl groups of PMMA.展开更多
Magnesium alloy has been generally accepted as an important biodegradable material on cardiovascular stent development for a long time. However, its limited biocompatibility, especially delayed endothelialization proc...Magnesium alloy has been generally accepted as an important biodegradable material on cardiovascular stent development for a long time. However, its limited biocompatibility, especially delayed endothelialization process restricts its further application. In this contribution, we modified the Mg-Zn-Y-Nd alloy surface with citric acid and dopamine via a layer-by-layer self-assembly assay, aiming at improving the biocompatibility of the magnesium alloy. The citric acid/dopamine(CA/PDA) layer exhibited a remarkable suppression of platelet activation/aggregation and thrombosis under 15 dyn/cm2 blood flowing. Inhibition on vascular smooth muscle cells growth and macrophages attachment/activation were also observed on this layer. In particular, the CA/PDA layer presented a promoted property for the vascular endothelial cells growth and spreading compared with the bare magnesium alloy, suggesting the pro-endotelialized function. In conclusion, this research may support potential application on surface modification of magnesium alloy based cardiovascular stents for better biocompatibility.展开更多
Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered asse...Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered assembly of graphene oxide(GO)nanosheets in solution films can be realized to obtain the high-quality and large-area reduced GO(rGO)films.The key to the success of this process primarily lies in the control of GO solution shear force direction with array capillaries,achieving oriented arrangement of GO nanosheets in the solution film.Secondly,the control of GO nanosheet concentration and solution viscosity during solvent evaporation of solution film is key to achieve the ordered and disordered assembly of GO,featuring the smooth and wrinkled structure rGO films,respectively.Subsequently,the resultant smooth rGO film with ordered assembly exhibits excellent thermal conductivity and electronic conductivity(over 1800 S·cm-1).Meanwhile,the wrinkled rGO film with disordered assembly can be used as a coating layer on Al current collectors,demonstrating anticorrosion properties and enhanced material adhesive stability.As a result,with such collectors,the high-voltage Li//NCM811 batteries show a 6-fold increase in cycle stability,and the lithium-sulfur batteries with high sulfur loading show a 3-fold increase in cycle stability.展开更多
Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-...Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-C_(3)N_(4) suffers from limited visible-light absorption and low charge-carrier mobility.In this study,a phosphorus-doped tubular carbon nitride(5P-TCN)was synthesized via a precursor self-assembly method using phosphoric acid and melamine as raw materials,eliminating the need for organic solvents or templates.The 5P-TCN catalyst demonstrated enhanced visible-light absorption,improved charge transfer capability,and a 5.25-fold increase in specific surface area(31.092 m^(2)/g),which provided abundant active sites to efficiently drive the PMS-assisted photocatalytic reaction.The 5P-TCN/vis/PMS system exhibited exceptional degradation performance for organic pollutants across a broad pH range(3–9),achieving over 92%degradation of Rhodamine B(RhB)within 15 min.Notably,the system retained>98%RhB degradation efficiency after three consecutive operational cycles,demonstrating robust operational stability and reusability.Moreover,key parameters influencing,active radi-cals,degradation pathways,and potential mechanisms for RhB degradation were systematically investigated.This work proposes a green and cost-effective strategy for developing high-efficiency photocatalysts,while demon-strating the exceptional capability of a PMS-assisted photocatalytic system for rapid degradation of RhB.展开更多
Fabric composites are widely applied as self-lubricating liner for radial spherical plain bearings owing to their excellent mechanical and tribological properties.Nevertheless,the poor interfacial strength between fib...Fabric composites are widely applied as self-lubricating liner for radial spherical plain bearings owing to their excellent mechanical and tribological properties.Nevertheless,the poor interfacial strength between fibers and the resin matrix limits the performance of composites utilized as tribomaterials.To overcome this drawback,a mild layer-by-layer(LbL)self-assembly method was successfully used to construct hybrid fabric composites in the present work.In addition,this investigation addressed the effect of self-assembly cycles on the friction and wear behaviors of hybrid fabric composites under dry sliding condition.The results demonstrate that fabric composites with three or more self-assembly cycles have significantly enhanced surface activities and anti-wear performances.The results obtained in this work can provide guidance in the preparation of self-lubricating liner composites and highlight how the LbL self-assembly techniques could influence the properties of hybrid fabric composites.展开更多
Graphene nanosheets are widely used in anti-corrosion polymeric coating as filler,owing to the excellent electrochemical inertness and barrier property.However,as the arrangement of graphene nanosheets is difficult to...Graphene nanosheets are widely used in anti-corrosion polymeric coating as filler,owing to the excellent electrochemical inertness and barrier property.However,as the arrangement of graphene nanosheets is difficult to form a perfect layered structure,polymeric coating with graphene nanosheets usually needs micron-scale thickness to ensure the enhancement of corrosion protection.In this work,layer-by-layer stacked graphene nanocoatings were fabricated on stainless steel by self-assembly based on Marangoni effect.The anti-corrosion property of graphene coatings were studied through Tafel polarization curves,electrochemical impedance spectroscopy and accelerated corrosion test with extra applied voltage.The self corrosion current density of optimized three-layered graphene coated sample was one quarter of that of bare stainless steel.And the self corrosion potential of optimized sample is increased to-0.045 V.According to the results,graphene nanocoatings composed of layered nanosheets exhibits good anticorrosion property.Besides,the self-assembly method provide a promising approach to make layeredstructure coating for other researches about 2 D material nanosheets.展开更多
Photocatalytic multilayer nanocomposite films composed of anatase TiO2 nanoparticles and lignosulfonates (LS) were fabricated on quartz slides by the layer-by-layer (LBL) self-assembly technique. X-ray photoelectr...Photocatalytic multilayer nanocomposite films composed of anatase TiO2 nanoparticles and lignosulfonates (LS) were fabricated on quartz slides by the layer-by-layer (LBL) self-assembly technique. X-ray photoelectron spectroscopy (XPS), UV-vis spectroscopy and atomic force microscopy (AFM) were used to characterize the TiO2/LS multilayer nanocomposite films. Moreover, the photocatalytic properties (decomposition of methyl orange and bacteria) of multilayer nanocomposite films were investigated. XPS results indicated that the intensities of titanium and sulfur peaks increased with the LBL deposition process. A linear increase in absorbance at 280 nm was found by UV-Vis spectroscopy, suggesting that stepwise multilayer growth occurs on the substrate and this deposition process is highly reproducible. AFM images showed that quartz slide was completely covered by TiO2 nanoparticles when a 10-bilayer multilayer film was formed. The decomposition efficiency of methyl orange by TiOz/LS multilayer films under the same UV irradiation time increased linearly with the number of TiO2 layers, and the results of decomposition of bacteria under UV irradiation showed that TiO2/LS multilayer nanocomposite films exhibited excellent decomposition activity of bacteria (Escherichia coil).展开更多
Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practica...Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practical performance is limited by inhomogeneous agglomeration,increased binder requirements,and high tortuosity within the electrode.To overcome these problems and high tortuosity within the electrode,this study introduces a pomegranate-like carbon microcluster composed of primary HCSs(P-CMs)as a novel Li metal host.This unique nanostructure can be easily prepared using the spray-drying technique,enabling its mass production.Comprehensive analyses with various tools demonstrate that compared with HCS hosts,the P-CM host requires a smaller amount of binder to fabricate a sufficiently robust and even surface electrode.Furthermore,owing to reduced tortuosity,the well-designed P-CM electrode can provide continuous and shortened pathways for electron/ion transport,accelerating the Li-ion transfer kinetics and prohibiting preferential Li plating at the upper region of the electrode.Due to these characteristics,Li metal can be effectively encapsulated in the large inner voids of the primary HCSs constituting the P-CM,thereby enhancing the electrochemical performance of P-CM hosts in Li metal batteries.Specifically,the Coulombic efficiency of the P-CM host can be maintained at 97%over 100 cycles,with a high Li deposition areal capacity of 3 mAh·cm^(-2)and long cycle life(1000 h,1 mA·cm^(-2),and 1.0 mAh·cm^(-2)).Furthermore,a full cell incorporating a LiFePO4 cathode exhibits excellent cycle life.展开更多
Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,whic...Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,which can be used to construct self-assembled nanoparticles in aqueous solution driven by hydrophobic interaction.Dynamic light scattering experiments show that M1 and M2 can be driven hydrophobically to aggregate into extremely stable nanoparticles in water at the micromolar concentrations.Fluorescence titration and zeta potential experiments support that the nanoparticles formed by M1 and M2 are able to efficiently encapsulate short DNA(sDNA).Fluorescence imaging and flow cytometry studies reveal that their nano sizes enable intracellular delivery of the encapsulated sDNA into both normal and cancer cells,with delivery percentage reaching up to 94%,while in vitro experiments indicate that the two compounds have excellent biocompatibility and low cytotoxicity.展开更多
In this paper, core–shell quantum dots(QDs) with two polar surface functional groups(ZnSe/ZnS–COOH QDs and ZnSe/ZnS–NH_2 QDs) are synthesized in an aqueous phase. Photoluminescence(PL) and absorption spectra clearl...In this paper, core–shell quantum dots(QDs) with two polar surface functional groups(ZnSe/ZnS–COOH QDs and ZnSe/ZnS–NH_2 QDs) are synthesized in an aqueous phase. Photoluminescence(PL) and absorption spectra clearly indicate luminescence down-shifting(LDS) properties. On the basis of QDs, surface functional group multilayer LDS films(MLDSs) are fabricated through an electrostatic layer-by-layer(LBL) self-assembly method. The PL intensity increases linearly with the number of bilayers, showing a regular and uniform film growth. When the M-LDS is placed on the surface of a Si-based solar cell as an optical conversion layer for the first time, the external quantum efficiency(EQE) and shortcircuit current density(Jsc) notably increases for the LDS process. The EQE response improves in a wavelength region extending from the UV region to the blue region, and its maximum increase reaches more than 15% between 350 nm and 460 nm.展开更多
The increasing consciousness about the depletion of natural resources and the sustainability agenda are the major driving forces to try to reuse and recycle organic materials such as agri-food and industrial wastes.In...The increasing consciousness about the depletion of natural resources and the sustainability agenda are the major driving forces to try to reuse and recycle organic materials such as agri-food and industrial wastes.In this context,keratin fibers,as a waste from the tannery industry,represent a great opportunity for the development of green functional materials.In this paper,keratin fibers were surface functionalized using the Layer-by-Layer(LbL)deposition technique and then freeze-dried in order to obtain a lightweight,fire-resistant,and sustainable material.The LbL coating,made with chitosan and carboxymethylated cellulose nanofibers,is fundamental in enabling the formation of a self-sustained structure after freeze-drying.The prepared porous fiber networks(density 100 kg m^(-3))display a keratin fiber content greater than 95 wt%and can easily self-extinguish the flame during a flammability test in a vertical configuration.In addition,during forced combustion tests(50 kW m^(-2))the samples exhibited a reduction of 37% in heat release rate and a reduction of 75%in smoke production if compared with a commercial polyurethane foam.The results obtained represent an excellent opportunity for the development of fire-safe sustainable materials based on fiber wastes.展开更多
Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous met...Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous metal detection,however,encounters unstable and weak signals due to nonuniform distribution of analytes.Herein,we developed an interface self-assembly(ISA)method to create a uniformly distributed gold nanolayer at a liquid-liquid interface for positive heavy metal ions capture and NELIBS analysis.The electrostatically selfassembled Au nanoparticles(NPs)-analytes membrane was prepared at the oil-water interface by injecting ethanol into the mixture of cyclohexane and Au NPs-analytes water solution.Then,the interface self-assembled Au NPs-analytes membrane was transformed onto a laser-processed superhydrophilic Si slide for detection.Three heavy metals(cadmium(Cd),barium(Ba),and chromium(Cr))were analyzed to evaluate the stability and sensitivity of the ISA method for NELIBS.The results(Cd:RSD=3.6%,LoD=0.654 mg/L;Ba:RSD=3.4%,LoD=0.236 mg/L;Cr:RSD=7.7%,LoD=1.367 mg/L)demonstrated signal enhancement and high-stable and ultrasensitive detection.The actual sample detection(Cd:RE=7.71%,Ba:RE=6.78%)illustrated great reliability.The ISA method,creating a uniform distribution of NP-analytes at the interface,has promising prospects in NELIBS.展开更多
Diphenylalanine and its analogs cause many concerns owing to their perfect self-assembly properties in the fields of biology,medicine,and nanotechnology.Experimental research has shown that diphenylalanine-based analo...Diphenylalanine and its analogs cause many concerns owing to their perfect self-assembly properties in the fields of biology,medicine,and nanotechnology.Experimental research has shown that diphenylalanine-based analogs with ethylenediamine linkers(PA,P=phenylalanine,and A=analog)can self-assemble into spherical assemblies,which can serve as novel anticancer drug carriers.In this work,to understand the assembly pathways,drug loading behavior,and formation mechanism of PA aggregates at the molecular level,we carried out dissipative particle dynamics(DPD)simulations of PA molecule systems.Our simulation results demonstrate that PA molecules spontaneously assemble into nanospheres and can self-assemble into drug-loaded nanospheres upon addition of the cancer chemotherapeutic agent doxorubicin(DOX).We also found that the hydrophobic side chain beads of PA molecules exhibited a unique onion-like distribution inside the nanospheres,which was not observed in the experiment.The onion-like nanospheres were verified by calculating the radial distribution function(RDF)of the DPD beads.Furthermore,based on the analysis of the percentages of different interaction components in the total nonbonded energies,main chain-side chain interactions between PA molecules may be important in the formation of onion-like nanospheres,and the synergistic effects of main chain-side chain,main chain-drug,side chain-drug,and main chain-solvent interactions are significant in the formation of drug-loaded nanospheres.These findings provide new insights into the structure and self-assembly pathway of PA assemblies,which may be helpful for the design of efficient and effective drug delivery systems.展开更多
The potential of metal nanoclusters in biomedical applications is limited due to aggregation-caused quenching(ACQ).In this study,an in situ self-assembled pitaya structure was proposed to obtain stable fluorescence em...The potential of metal nanoclusters in biomedical applications is limited due to aggregation-caused quenching(ACQ).In this study,an in situ self-assembled pitaya structure was proposed to obtain stable fluorescence emission through protein coronas-controlled distance between gold nanoclusters(Au NCs).Interestingly,the gold ion complexes coated with proteins of low isoelectric point(pI)nucleate at the secondary structure of proteins with high p I through ionic exchange within cells,generating fluorescent Au NCs.It is worth noting that due to the steric hindrance formed by the protein coronas on the surface of Au NCs,the distance between Au NCs can be controlled,avoiding electron transfer caused by close proximity of Au NCs and inhibiting fluorescence ACQ.This strategy can achieve fluorescence imaging of clinical tissue samples without observable side effects.Therefore,this study proposes a distance-controllable self-assembled pitaya structure to provide a new approach for Au NCs with stable fluorescence.展开更多
The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycola...The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycolamide,MPyEDChDGA) with a new structure was synthesized,and the pyridine group was successfully grafted onto the 3-oxadiglycolamide structure.Using MPyEDChDGA for efficient enrichment of rare earth ions,the self-assembled solids were recovered by simple filtration without further backextraction and final precipitation,achieving a one-step strategy for the recovery of rare earth ions.Several important parameters affecting the self-assembly extraction,including pH,diluent,temperature,and extractant concentration,were systematically evaluated using La(NO_(3))_(3),Tb(NO_(3))_(3),and Lu(NO_(3))_(3) as representatives.The self-assembled solids were investigated in detail by X-ray diffraction(XRD),scanning electron microscopy(SEM),1H nuclear magnetic resonance(1H NMR),Fourier transform infrared spectroscopy(FT-IR),Raman,and X-ray photoelectron spectroscopy(XPS) analyses.The stoichiometry of the extraction species was characterized using the Job's method and electrospray ionization mass spectrometry(ESI-MS).In addition,MPyEDChDGA was applied to the recovery of Sm in SmCoCu simulated liquid,and the results show that MPyEDChDGA has good selectivity of Sm from transition metals(Co,Cu).The separation factor of Sm/Co can reach 6281±117,which provides a new approach to recovering Sm from SmCoCu scrap magnets.This study presents an efficient and convenient new strategy for the recovery and separation of rare earth elements.展开更多
Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AAB...Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AABCs presents challenges,which greatly limits the exploration of their self-assembly behaviors.In this work,we employed dissipative particle dynamics(DPD)simulations to investigate the self-assembly behaviors of AABCs in selective solution.By varying the copolymer concentration and structure,we conducted the self-assembly phase diagrams of AABCs,revealing complex morphologies such as channelized micelles with one or more solvophilic channels.Moreover,the number,surface area,and one-dimensional density distribution of the channelized micelles were calculated to demonstrate the internal structure and morphological transformation during the self-assembly process.Our findings indicate that the morphology of the internal solvophilic channels is greatly influenced by the copolymer structure,concentration,and interaction parameters between the different side chains.The simulation results are consistent with available experimental observations,which can offer theoretical insights into the self-assembly of AABCs.展开更多
The self-assembly and photothermal application studies of interlocked compounds has been attracting increasing attention during the last decades.Nevertheless,the synthesis of a series of interlocked topologies possess...The self-assembly and photothermal application studies of interlocked compounds has been attracting increasing attention during the last decades.Nevertheless,the synthesis of a series of interlocked topologies possessing similar structural characteristic and clarifying their photothermal performance law remains a challenge.Herein,we introduce a new dipyridinyl ligand L1 featuring two methoxy groups,which act as electron-donating species and provide electrons to the central benzene ring,resulting in an enhanced electron rich effect.Previous research indicates that this feature significantly contributes to forming π-stacking interactions.Furthermore,four half-sandwich rhodium-based building blocks exhibiting different metal-to-metal distances and conjugated effect were selected and used to combine with L1 for the synthesis of[2]catenanes and metallamacrocycles for studying the influence of half-sandwich building blocks on photothermal conversion performance under the same accumulation effect.Three new metalla[2]catenanes and one metallamacrocycle have been obtained in high yields and their structure has been unambiguously confirmed by single crystal X-ray diffraction analysis,NMR spectroscopy,and ESI-TOF-MS.In addition,dynamic structural transformation between[2]catenanes and the corresponding metallamacrocycles has been observed through concentration changes and polar solvent induced effect.Photothermal conversion abilities of the isolated complexes were studied and we observed that[2]catenane 3a displayed significant temperature changes(from 25.8℃ to 50.3℃)under laser irradiation of 1.5 W/cm^(2),thereby reaching a photothermal conversion efficiency of 40.42%.Recorded EPR data indicates that the synergistic cooperation of the free radical effect at the building unit and the stacking effect of[2]catenanes most likely generated photothermal conversion.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51273063 and 51003028)the Fundamental Research Funds for the Central Universities+1 种基金the Higher School Specialized Research Fund for the Doctoral Program(No.20110074110003)111 Project Grant(No.B08021)
文摘Spherical polyelectrolyte brushes (SPBs) consisting of polystyrene (PS) core and poly(2-aminoethyl methacrylate hydrochloride) (PAEMH) shell were prepared by photo-emulsion polymerization. Au nanoparticles (Au-NPs) with controlled size and size distribution were synthesized in situ using SPBs as nanoreactors. Via layer-by-layer deposition technique on the surface of SPBs, nano-composite particles with Au/Ag-NPs bilayer and Au/Ag/Au-NPs trilayer were prepared. The structures of the as-prepared Au/Ag multilayer SPBs were characterized by UV-Vis spectroscopy, TEM, ICP-AES and DLS. The charge reversal of the nano-composite particles observed by zeta potential confirmed the success of layer-by-layer assembly. The Au/Ag-NPs bilayer nano-composite particles showed high catalytic efficiency with an apparent activation energy of about 41.2 kJ/mol in the reduction reaction of 4-nitrophenol to 4-aminophenol in the existence of sodium borohydride monitored. The catalytic activity ofAu/Ag-NPs multilayer SPBs close to that of Au-NPs SPBs and much higher than that of Ag-NPs SPBs reveals its potential applications in cost-effective catalysts with high-performance.
文摘Orthopedic implants for the treatment of bone defects from various causes have been challenged by insufficient osseointegration,bacterial infection,oxidative stress,immune rejection,and insufficient individualized treatment.These challenges not only impact treatment outcomes but also severely impact patients’daily lives.Layer-by-Layer(LbL)serves as a simple surface coating technique,in simple terms,to functionalize implants by sequentially adsorbing oppositely charged materials onto a substrate.In orthopaedics,LbL self-assembly technology solves some of the challenges by loading various drugs or biological agents on the implant surface and controlling their release precisely to the site of bone defects in a personalized way.This review will introduce the basic principle and the development of LbL in orthopaedics,review and analyze the chemical strategy of LbL in the preparation of bone implants to ensure the stability of the implant,and introduce the use of LbL bone implants in orthopaedics in recent years.The application of LbL includes the realization of programmed drug delivery and sustained release,thereby promoting osseointegration and the formation of new blood vessels,antibacterial,antioxidant,etc.This review focuses on the LbL technology,involving the technology selection for the preparation of bone implants,the chemical strategies of the stability guarantee of LbL implants,the pharmacological properties,loading and release mechanisms of loaded drugs,and the molecular mechanisms of osteogenesis and angiogenesis.The aim of this review is to provide an overview of current research advances,and a prospect in this field was also described.
基金National Undergraduate Training Program for Innovation and Entrepreneurship of China (Grant No.202210288027).
文摘The abuse of plastic food packaging has brought about severe white pollution issues around the world.Developing green and sustainable biomass packaging is an effective way to solve this problem.Hence,a chitosan/sodium alginate-based multilayer film is fabricated via a layer-by-layer(LBL)self-assembly method.With the help of superior interaction between the layers,the multilayer film possesses excellent mechanical properties(with a tensile strength of 50 MPa).Besides,the film displays outstanding water retention property(blocking moisture of 97.56%)and ultraviolet blocking property.Anthocyanin is introduced into the film to detect the food quality since it is one natural plant polyphenol that is sensitive to the pH changes ranging from 1 to 13 in food when spoilage occurs.It is noted that the film is also bacteriostatic which is desired for food packaging.This study describes a simple technique for the development of advanced multifunctional and fully biodegradable food packaging film and it is a sustainable alternative to plastic packaging.
基金Funded by the Wuhan Science and Technology Bureau(No.2020020601012279)。
文摘A film with“brick-and-mortar”structure was prepared by layer-by-layer(LBL)technique using polyvinyl alcohol(PVA)and polymethyl methacrylate(PMMA)as the flexible material or“mortar”and mica as the rigid material or“brick”.The film deposited on a glass slide after self-assembly cycles had a thickness of 3μm thick and an uneven,wavy surface.The film exhibits enhanced mechanical properties,i e,the hardness and indentation modulus values could reach 6.14 and 68.41 GPa,respectively.The hardness and elastic toughness were found to be depended on three factors,i e,the ratio of PVA to mica,the number of self-assembly cycles,and the pretreatment method of the mica suspension.The self-assembly process was driven by formation of the hydrogen bonds between the silanol groups of mica and the hydroxyl groups of PVA and carbonyl groups of PMMA.
基金supported by the National Key Research and Development Program of China(Grant Nos.2016YFC1102403&2017YFGX090043-04)Fostering Talents of National Natural Science Foundation of China and Henan Province(Grant No.U1504310)National Center for International Research of Micro-nano Molding Technology&Key Laboratory for Micro Molding Technology of Henan Province(Grant No.MMT2017-01)
文摘Magnesium alloy has been generally accepted as an important biodegradable material on cardiovascular stent development for a long time. However, its limited biocompatibility, especially delayed endothelialization process restricts its further application. In this contribution, we modified the Mg-Zn-Y-Nd alloy surface with citric acid and dopamine via a layer-by-layer self-assembly assay, aiming at improving the biocompatibility of the magnesium alloy. The citric acid/dopamine(CA/PDA) layer exhibited a remarkable suppression of platelet activation/aggregation and thrombosis under 15 dyn/cm2 blood flowing. Inhibition on vascular smooth muscle cells growth and macrophages attachment/activation were also observed on this layer. In particular, the CA/PDA layer presented a promoted property for the vascular endothelial cells growth and spreading compared with the bare magnesium alloy, suggesting the pro-endotelialized function. In conclusion, this research may support potential application on surface modification of magnesium alloy based cardiovascular stents for better biocompatibility.
基金the National Natural Science Foundation of China(No.U22A20437)Joint Fund of Science and Technology R&D Plan of Henan Province(No.222301420005)Program for Innovative Research Team(in Science and Technology)in University of Henan Province(No.24IRTSTHN001)for financial support.
文摘Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered assembly of graphene oxide(GO)nanosheets in solution films can be realized to obtain the high-quality and large-area reduced GO(rGO)films.The key to the success of this process primarily lies in the control of GO solution shear force direction with array capillaries,achieving oriented arrangement of GO nanosheets in the solution film.Secondly,the control of GO nanosheet concentration and solution viscosity during solvent evaporation of solution film is key to achieve the ordered and disordered assembly of GO,featuring the smooth and wrinkled structure rGO films,respectively.Subsequently,the resultant smooth rGO film with ordered assembly exhibits excellent thermal conductivity and electronic conductivity(over 1800 S·cm-1).Meanwhile,the wrinkled rGO film with disordered assembly can be used as a coating layer on Al current collectors,demonstrating anticorrosion properties and enhanced material adhesive stability.As a result,with such collectors,the high-voltage Li//NCM811 batteries show a 6-fold increase in cycle stability,and the lithium-sulfur batteries with high sulfur loading show a 3-fold increase in cycle stability.
文摘Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-C_(3)N_(4) suffers from limited visible-light absorption and low charge-carrier mobility.In this study,a phosphorus-doped tubular carbon nitride(5P-TCN)was synthesized via a precursor self-assembly method using phosphoric acid and melamine as raw materials,eliminating the need for organic solvents or templates.The 5P-TCN catalyst demonstrated enhanced visible-light absorption,improved charge transfer capability,and a 5.25-fold increase in specific surface area(31.092 m^(2)/g),which provided abundant active sites to efficiently drive the PMS-assisted photocatalytic reaction.The 5P-TCN/vis/PMS system exhibited exceptional degradation performance for organic pollutants across a broad pH range(3–9),achieving over 92%degradation of Rhodamine B(RhB)within 15 min.Notably,the system retained>98%RhB degradation efficiency after three consecutive operational cycles,demonstrating robust operational stability and reusability.Moreover,key parameters influencing,active radi-cals,degradation pathways,and potential mechanisms for RhB degradation were systematically investigated.This work proposes a green and cost-effective strategy for developing high-efficiency photocatalysts,while demon-strating the exceptional capability of a PMS-assisted photocatalytic system for rapid degradation of RhB.
基金National Nature Science Foundation of China(Nos.51805516 and 51675252).
文摘Fabric composites are widely applied as self-lubricating liner for radial spherical plain bearings owing to their excellent mechanical and tribological properties.Nevertheless,the poor interfacial strength between fibers and the resin matrix limits the performance of composites utilized as tribomaterials.To overcome this drawback,a mild layer-by-layer(LbL)self-assembly method was successfully used to construct hybrid fabric composites in the present work.In addition,this investigation addressed the effect of self-assembly cycles on the friction and wear behaviors of hybrid fabric composites under dry sliding condition.The results demonstrate that fabric composites with three or more self-assembly cycles have significantly enhanced surface activities and anti-wear performances.The results obtained in this work can provide guidance in the preparation of self-lubricating liner composites and highlight how the LbL self-assembly techniques could influence the properties of hybrid fabric composites.
基金the financial support by the National Natural Science Foundation of China(Nos.51573201,51501209,201675165 and 61901460)NSFC-Zhejiang Joint Fund for the Integration of Industrialization and Informatization(No.U1709205)+7 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA22000000)Scientific Instrument Developing Project of the Chinese Academy of Sciences(No.YZ201640)Science and Technology Major Project of Ningbo(Nos.2016S1002 and 2016B10038)International S&T Cooperation Program of Ningbo(No.2017D10016)China Postdoctoral Science Foundation(No.2019M653125)for financial supportthe Chinese Academy of Sciences for Hundred Talents ProgramChinese Central Government for Thousand Young Talents Program3315 Program of Ningbo。
文摘Graphene nanosheets are widely used in anti-corrosion polymeric coating as filler,owing to the excellent electrochemical inertness and barrier property.However,as the arrangement of graphene nanosheets is difficult to form a perfect layered structure,polymeric coating with graphene nanosheets usually needs micron-scale thickness to ensure the enhancement of corrosion protection.In this work,layer-by-layer stacked graphene nanocoatings were fabricated on stainless steel by self-assembly based on Marangoni effect.The anti-corrosion property of graphene coatings were studied through Tafel polarization curves,electrochemical impedance spectroscopy and accelerated corrosion test with extra applied voltage.The self corrosion current density of optimized three-layered graphene coated sample was one quarter of that of bare stainless steel.And the self corrosion potential of optimized sample is increased to-0.045 V.According to the results,graphene nanocoatings composed of layered nanosheets exhibits good anticorrosion property.Besides,the self-assembly method provide a promising approach to make layeredstructure coating for other researches about 2 D material nanosheets.
文摘Photocatalytic multilayer nanocomposite films composed of anatase TiO2 nanoparticles and lignosulfonates (LS) were fabricated on quartz slides by the layer-by-layer (LBL) self-assembly technique. X-ray photoelectron spectroscopy (XPS), UV-vis spectroscopy and atomic force microscopy (AFM) were used to characterize the TiO2/LS multilayer nanocomposite films. Moreover, the photocatalytic properties (decomposition of methyl orange and bacteria) of multilayer nanocomposite films were investigated. XPS results indicated that the intensities of titanium and sulfur peaks increased with the LBL deposition process. A linear increase in absorbance at 280 nm was found by UV-Vis spectroscopy, suggesting that stepwise multilayer growth occurs on the substrate and this deposition process is highly reproducible. AFM images showed that quartz slide was completely covered by TiO2 nanoparticles when a 10-bilayer multilayer film was formed. The decomposition efficiency of methyl orange by TiOz/LS multilayer films under the same UV irradiation time increased linearly with the number of TiO2 layers, and the results of decomposition of bacteria under UV irradiation showed that TiO2/LS multilayer nanocomposite films exhibited excellent decomposition activity of bacteria (Escherichia coil).
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.2020R1C1C1003375)。
文摘Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practical performance is limited by inhomogeneous agglomeration,increased binder requirements,and high tortuosity within the electrode.To overcome these problems and high tortuosity within the electrode,this study introduces a pomegranate-like carbon microcluster composed of primary HCSs(P-CMs)as a novel Li metal host.This unique nanostructure can be easily prepared using the spray-drying technique,enabling its mass production.Comprehensive analyses with various tools demonstrate that compared with HCS hosts,the P-CM host requires a smaller amount of binder to fabricate a sufficiently robust and even surface electrode.Furthermore,owing to reduced tortuosity,the well-designed P-CM electrode can provide continuous and shortened pathways for electron/ion transport,accelerating the Li-ion transfer kinetics and prohibiting preferential Li plating at the upper region of the electrode.Due to these characteristics,Li metal can be effectively encapsulated in the large inner voids of the primary HCSs constituting the P-CM,thereby enhancing the electrochemical performance of P-CM hosts in Li metal batteries.Specifically,the Coulombic efficiency of the P-CM host can be maintained at 97%over 100 cycles,with a high Li deposition areal capacity of 3 mAh·cm^(-2)and long cycle life(1000 h,1 mA·cm^(-2),and 1.0 mAh·cm^(-2)).Furthermore,a full cell incorporating a LiFePO4 cathode exhibits excellent cycle life.
文摘Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,which can be used to construct self-assembled nanoparticles in aqueous solution driven by hydrophobic interaction.Dynamic light scattering experiments show that M1 and M2 can be driven hydrophobically to aggregate into extremely stable nanoparticles in water at the micromolar concentrations.Fluorescence titration and zeta potential experiments support that the nanoparticles formed by M1 and M2 are able to efficiently encapsulate short DNA(sDNA).Fluorescence imaging and flow cytometry studies reveal that their nano sizes enable intracellular delivery of the encapsulated sDNA into both normal and cancer cells,with delivery percentage reaching up to 94%,while in vitro experiments indicate that the two compounds have excellent biocompatibility and low cytotoxicity.
基金Project supported by the Natural Science Foundation of Shandong Province,China(Grant No.ZR2017PF011)the National Natural Science Foundation of China(Grant No.E020701)the Doctoral Scientific Research Foundation of Binzhou University,China(Grant No.2014Y10)
文摘In this paper, core–shell quantum dots(QDs) with two polar surface functional groups(ZnSe/ZnS–COOH QDs and ZnSe/ZnS–NH_2 QDs) are synthesized in an aqueous phase. Photoluminescence(PL) and absorption spectra clearly indicate luminescence down-shifting(LDS) properties. On the basis of QDs, surface functional group multilayer LDS films(MLDSs) are fabricated through an electrostatic layer-by-layer(LBL) self-assembly method. The PL intensity increases linearly with the number of bilayers, showing a regular and uniform film growth. When the M-LDS is placed on the surface of a Si-based solar cell as an optical conversion layer for the first time, the external quantum efficiency(EQE) and shortcircuit current density(Jsc) notably increases for the LDS process. The EQE response improves in a wavelength region extending from the UV region to the blue region, and its maximum increase reaches more than 15% between 350 nm and 460 nm.
基金supported by the Italian Ministry of University(MIUR)call PRIN 2017 with the project“PANACEA:A technology Platform for the sustainable recovery and advanced use of NAnostructured CEllulose from Agro-food residues”(grant No.2017LEPH3M).
文摘The increasing consciousness about the depletion of natural resources and the sustainability agenda are the major driving forces to try to reuse and recycle organic materials such as agri-food and industrial wastes.In this context,keratin fibers,as a waste from the tannery industry,represent a great opportunity for the development of green functional materials.In this paper,keratin fibers were surface functionalized using the Layer-by-Layer(LbL)deposition technique and then freeze-dried in order to obtain a lightweight,fire-resistant,and sustainable material.The LbL coating,made with chitosan and carboxymethylated cellulose nanofibers,is fundamental in enabling the formation of a self-sustained structure after freeze-drying.The prepared porous fiber networks(density 100 kg m^(-3))display a keratin fiber content greater than 95 wt%and can easily self-extinguish the flame during a flammability test in a vertical configuration.In addition,during forced combustion tests(50 kW m^(-2))the samples exhibited a reduction of 37% in heat release rate and a reduction of 75%in smoke production if compared with a commercial polyurethane foam.The results obtained represent an excellent opportunity for the development of fire-safe sustainable materials based on fiber wastes.
基金supported by the National Natural Science Foundation of China(No.62075069 and 52303092)the Water Conservancy Technology project of Hunan Province,China(XSKJ2021000-32)+1 种基金the City University of Hong Kong(#7005507)the Open Project of Yunnan Precious Metals Laboratory Co.,Ltd(grant number YPML-2023050278).
文摘Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous metal detection,however,encounters unstable and weak signals due to nonuniform distribution of analytes.Herein,we developed an interface self-assembly(ISA)method to create a uniformly distributed gold nanolayer at a liquid-liquid interface for positive heavy metal ions capture and NELIBS analysis.The electrostatically selfassembled Au nanoparticles(NPs)-analytes membrane was prepared at the oil-water interface by injecting ethanol into the mixture of cyclohexane and Au NPs-analytes water solution.Then,the interface self-assembled Au NPs-analytes membrane was transformed onto a laser-processed superhydrophilic Si slide for detection.Three heavy metals(cadmium(Cd),barium(Ba),and chromium(Cr))were analyzed to evaluate the stability and sensitivity of the ISA method for NELIBS.The results(Cd:RSD=3.6%,LoD=0.654 mg/L;Ba:RSD=3.4%,LoD=0.236 mg/L;Cr:RSD=7.7%,LoD=1.367 mg/L)demonstrated signal enhancement and high-stable and ultrasensitive detection.The actual sample detection(Cd:RE=7.71%,Ba:RE=6.78%)illustrated great reliability.The ISA method,creating a uniform distribution of NP-analytes at the interface,has promising prospects in NELIBS.
基金financially supported by the National Natural Science Foundation of China(Nos.20904047 and 12074151)the Natural Science Foundation of Zhejiang Province(Nos.LY17A040001 and LY19F03004)。
文摘Diphenylalanine and its analogs cause many concerns owing to their perfect self-assembly properties in the fields of biology,medicine,and nanotechnology.Experimental research has shown that diphenylalanine-based analogs with ethylenediamine linkers(PA,P=phenylalanine,and A=analog)can self-assemble into spherical assemblies,which can serve as novel anticancer drug carriers.In this work,to understand the assembly pathways,drug loading behavior,and formation mechanism of PA aggregates at the molecular level,we carried out dissipative particle dynamics(DPD)simulations of PA molecule systems.Our simulation results demonstrate that PA molecules spontaneously assemble into nanospheres and can self-assemble into drug-loaded nanospheres upon addition of the cancer chemotherapeutic agent doxorubicin(DOX).We also found that the hydrophobic side chain beads of PA molecules exhibited a unique onion-like distribution inside the nanospheres,which was not observed in the experiment.The onion-like nanospheres were verified by calculating the radial distribution function(RDF)of the DPD beads.Furthermore,based on the analysis of the percentages of different interaction components in the total nonbonded energies,main chain-side chain interactions between PA molecules may be important in the formation of onion-like nanospheres,and the synergistic effects of main chain-side chain,main chain-drug,side chain-drug,and main chain-solvent interactions are significant in the formation of drug-loaded nanospheres.These findings provide new insights into the structure and self-assembly pathway of PA assemblies,which may be helpful for the design of efficient and effective drug delivery systems.
基金supported by the National Natural Science Foundation of China(Nos.82061148012,82027806,21974019)SEU Innovation Capability Enhancement Plan for Doctoral Students(No.CXJH_SEU 24138)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX24_0469)。
文摘The potential of metal nanoclusters in biomedical applications is limited due to aggregation-caused quenching(ACQ).In this study,an in situ self-assembled pitaya structure was proposed to obtain stable fluorescence emission through protein coronas-controlled distance between gold nanoclusters(Au NCs).Interestingly,the gold ion complexes coated with proteins of low isoelectric point(pI)nucleate at the secondary structure of proteins with high p I through ionic exchange within cells,generating fluorescent Au NCs.It is worth noting that due to the steric hindrance formed by the protein coronas on the surface of Au NCs,the distance between Au NCs can be controlled,avoiding electron transfer caused by close proximity of Au NCs and inhibiting fluorescence ACQ.This strategy can achieve fluorescence imaging of clinical tissue samples without observable side effects.Therefore,this study proposes a distance-controllable self-assembled pitaya structure to provide a new approach for Au NCs with stable fluorescence.
基金Project supported by the Natural Science Foundation of Shandong Province (ZR2022QB067)。
文摘The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycolamide,MPyEDChDGA) with a new structure was synthesized,and the pyridine group was successfully grafted onto the 3-oxadiglycolamide structure.Using MPyEDChDGA for efficient enrichment of rare earth ions,the self-assembled solids were recovered by simple filtration without further backextraction and final precipitation,achieving a one-step strategy for the recovery of rare earth ions.Several important parameters affecting the self-assembly extraction,including pH,diluent,temperature,and extractant concentration,were systematically evaluated using La(NO_(3))_(3),Tb(NO_(3))_(3),and Lu(NO_(3))_(3) as representatives.The self-assembled solids were investigated in detail by X-ray diffraction(XRD),scanning electron microscopy(SEM),1H nuclear magnetic resonance(1H NMR),Fourier transform infrared spectroscopy(FT-IR),Raman,and X-ray photoelectron spectroscopy(XPS) analyses.The stoichiometry of the extraction species was characterized using the Job's method and electrospray ionization mass spectrometry(ESI-MS).In addition,MPyEDChDGA was applied to the recovery of Sm in SmCoCu simulated liquid,and the results show that MPyEDChDGA has good selectivity of Sm from transition metals(Co,Cu).The separation factor of Sm/Co can reach 6281±117,which provides a new approach to recovering Sm from SmCoCu scrap magnets.This study presents an efficient and convenient new strategy for the recovery and separation of rare earth elements.
基金supported by the National Science Foundation for Distinguished Young Scholars(No.52325308)the National Natural Science Foundation of China(Nos.52273008 and 52073092)+1 种基金Shanghai Scientific and Technological Innovation Projects(No.22ZR1479300)Shanghai Rising-Star Program(No.23QA1402500).
文摘Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AABCs presents challenges,which greatly limits the exploration of their self-assembly behaviors.In this work,we employed dissipative particle dynamics(DPD)simulations to investigate the self-assembly behaviors of AABCs in selective solution.By varying the copolymer concentration and structure,we conducted the self-assembly phase diagrams of AABCs,revealing complex morphologies such as channelized micelles with one or more solvophilic channels.Moreover,the number,surface area,and one-dimensional density distribution of the channelized micelles were calculated to demonstrate the internal structure and morphological transformation during the self-assembly process.Our findings indicate that the morphology of the internal solvophilic channels is greatly influenced by the copolymer structure,concentration,and interaction parameters between the different side chains.The simulation results are consistent with available experimental observations,which can offer theoretical insights into the self-assembly of AABCs.
基金supported by the National Natural Science Foundation of China(Nos.22471113 and 22171123)Natural Science Foundation of Henan Province(Nos.242300421139,232300421232)the Science and Technology Innovation Talent Program of University in Henan Province(No.25HASTIT001)。
文摘The self-assembly and photothermal application studies of interlocked compounds has been attracting increasing attention during the last decades.Nevertheless,the synthesis of a series of interlocked topologies possessing similar structural characteristic and clarifying their photothermal performance law remains a challenge.Herein,we introduce a new dipyridinyl ligand L1 featuring two methoxy groups,which act as electron-donating species and provide electrons to the central benzene ring,resulting in an enhanced electron rich effect.Previous research indicates that this feature significantly contributes to forming π-stacking interactions.Furthermore,four half-sandwich rhodium-based building blocks exhibiting different metal-to-metal distances and conjugated effect were selected and used to combine with L1 for the synthesis of[2]catenanes and metallamacrocycles for studying the influence of half-sandwich building blocks on photothermal conversion performance under the same accumulation effect.Three new metalla[2]catenanes and one metallamacrocycle have been obtained in high yields and their structure has been unambiguously confirmed by single crystal X-ray diffraction analysis,NMR spectroscopy,and ESI-TOF-MS.In addition,dynamic structural transformation between[2]catenanes and the corresponding metallamacrocycles has been observed through concentration changes and polar solvent induced effect.Photothermal conversion abilities of the isolated complexes were studied and we observed that[2]catenane 3a displayed significant temperature changes(from 25.8℃ to 50.3℃)under laser irradiation of 1.5 W/cm^(2),thereby reaching a photothermal conversion efficiency of 40.42%.Recorded EPR data indicates that the synergistic cooperation of the free radical effect at the building unit and the stacking effect of[2]catenanes most likely generated photothermal conversion.