Core-shell colloidal particles with a polymer layer have broad applications in different areas.Herein,we developed a two-step method combining aqueous surface-initiated photoinduced polymerization-induced self-assembl...Core-shell colloidal particles with a polymer layer have broad applications in different areas.Herein,we developed a two-step method combining aqueous surface-initiated photoinduced polymerization-induced self-assembly and photoinduced seeded reversible addition-fragmentation chain transfer(RAFT)polymerization to prepare a diverse set of core-shell colloidal particles with a well-defined polymer layer.Chemical compositions,structures,and thicknesses of polymer layers could be conveniently regulated by using different types of monomers and feed[monomer]/[chain transfer agent]ratios during seeded RAFT polymerization.展开更多
Available onlineSilicon monoxide(SiO)is a promising anode material fo r lithium-ion batteries(LIBs)due to its high theoretical specific capacity(~2400 mAh/g),low working potential(<0.5 V vs.Li^+/Li),low cost,easy s...Available onlineSilicon monoxide(SiO)is a promising anode material fo r lithium-ion batteries(LIBs)due to its high theoretical specific capacity(~2400 mAh/g),low working potential(<0.5 V vs.Li^+/Li),low cost,easy synthesis,nontoxicity,abundant natural source and smaller volume expansion than Si.However,low intrinsic electrical conductivity,low initial Coulombic efficiency(ICE)and inevitable volume expansion(~200%)impede its practical application.Here we fabricate SiO/wrinkled MXene composite(SiO-WM)by an electrostatic self-assembly method.Importantly,this method is simple,scalable and taking into account all the issues of SiO.As a result,the SiO-WM exhibits imp roved rate capability,cycling performance and ICE than bare SiO.展开更多
Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spect...Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spectroscopy （FT-IR） and scanning electron microscopy （SEM）. Methyl orange was used to estimate the photocatalytic activity of the materials. The effects of the calcination temperature and silane dosage on the photocatalytic activity of the samples were investigated. The experimental results show that the bentonite facilitates the formation of anatase and restrains the transformation of anatase to rutile. Part of nano-size TiO2 particles insert into the galleries of bentonite. The photocatalysts exhibit a synergistic effect of adsorption and photocatalysis on methyl orange. Photocatalysts prepared by ESAM method exhibit higher photocatalytic activity and better recycle ability than those of the traditional method.展开更多
Constructing electrode materials with large capacity and good conductivity is an effective approach to improve the capacitor performance of asymmetric supercapacitors(ASCs).In this paper,ZnCo_(2)S_(4)core-shell nanosp...Constructing electrode materials with large capacity and good conductivity is an effective approach to improve the capacitor performance of asymmetric supercapacitors(ASCs).In this paper,ZnCo_(2)S_(4)core-shell nanospheres are constructed by two-step hydrothermal method.In order to improve the chemical activity of ZnCo_(2)S_(4),ZnCo_(2)S_(4)is activated using cetyltrimethylammonium bromide(CTAB).Then,MXene nanosheets are fixed on the surface of ZnCo_(2)S_(4)by electrostatic selfassembly method to improve the specific surface area of ZnCo_(2)S_(4)and MXene-wrapped ZnCo_(2)S_(4)composite is prepared in this work.Owing to the synergy effect between MXene nanosheets and ZnCo_(2)S_(4)core-shell nanospheres,the as-prepared composite displays fast ion transfer rate and charge/discharge process.The capacity of the MXenewrapped ZnCo_(2)S_(4)composite can reach 1072 F·g^(-1),which is far larger than that of ZnCo_(2)S_(4)(407 F·g^(-1))at 1 A·g^(-1).An ASC device is assembled,which delivers 1.7 V potential window and superior cyclic stability(95.41%capacitance retention).Furthermore,energy density of this device is up to 30.46 Wh·kg^(-1)at a power density of850 W·kg^(-1).The above results demonstrate that MXenewrapped ZnCo_(2)S_(4)composite has great application prospects in electrochemical energy storage field.展开更多
The cooperative electrostatic attraction and π-π aromatic stacking interactions between tetrahedral tetrapyridinium TP and three tetraanionic tetraphenylethylene derivatives TPE-1～3 led to the formation of a new ki...The cooperative electrostatic attraction and π-π aromatic stacking interactions between tetrahedral tetrapyridinium TP and three tetraanionic tetraphenylethylene derivatives TPE-1～3 led to the formation of a new kind of supramolecular polymer networks in water, which have been confirmed by^1 H NMR,fluorescence, isothermal titration calorimetric(ITC) and dynamic light scattering(DLS) experiments. ITC studies show that the contributions of enthalpy and entropy were comparable, reflecting the importance of hydrophobicity in driving the intermolecular aromatic stacking. DLS experiments indicate that the linear supramolecular polymers formed by these tetratopic monomers further aggregated into networks of 10~2-nm size.展开更多
Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (...Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (ESA) method. The whole self-assemble process, the function of surfactant and the effect of TiO_2 slurry′s concentration to the self-assemble were discussed. The isoelectric point of TiO_2 slurry measured by experiment is 6.8. The results show that whatever the concentration of the TiO_2 dispersion, a flat and compact adsorbed monolayer on the optic fiber can be built in a stable dispersion at lower pH. There is a adsorbed equilibrium on the substrate (fiber)/solution interface when enough time of incubation is given. A rough and loosen adsorbed layer is formed on the fiber surface by immersed the substrate in a high pH dispersion (pH>10) because the presence of hydroxyl on particle surface. Film thickness can be controlled by controlling the number of layers in the film.展开更多
Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin f...Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin films on si/icon and quartz substrates. The paniculate thin films were characterized by UV-vis spea-troscopy, surface, enhanced Raman scattering, atomic force microscopy and resistivity measurements. Due to the interparticle coupling between individual gold particles, an obvious collective particle plasmon resonance was ob-served on UV-vis spectra , and the particulate thin films exhibited a strong SERS effect. For multilayer thin films with a high particle coverage on substrates , resistivity of the order of 10-4 Ω·cm was yielded.展开更多
Metal-organic framework(MOF)-derived carbon composites have been considered as the promising materials for energy storage.However,the construction of MOF-based composites with highly controllable mode via the liquid-l...Metal-organic framework(MOF)-derived carbon composites have been considered as the promising materials for energy storage.However,the construction of MOF-based composites with highly controllable mode via the liquid-liquid synthesis method has a great challenge because of the simultaneous heterogeneous nucleation on substrates and the self-nucleation of individual MOF nanocrystals in the liquid phase.Herein,we report a bidirectional electrostatic generated self-assembly strategy to achieve the precisely controlled coatings of single-layer nanoscale MOFs on a range of substrates,including carbon nanotubes(CNTs),graphene oxide(GO),MXene,layered double hydroxides(LDHs),MOFs,and SiO_(2).The obtained MOF-based nanostructured carbon composite exhibits the hierarchical porosity(V_(meso)/V_(micro)∶2.4),ultrahigh N content of 12.4 at.%and"dual electrical conductive networks."The assembled aqueous zinc-ion hybrid capacitor(ZIC)with the prepared nanocarbon composite as a cathode shows a high specific capacitance of 236 F g^(-1)at 0.5 A g^(-1),great rate performance of 98 F g^(-1)at 100 A g^(-1),and especially,an ultralong cycling stability up to 230000 cycles with the capacitance retention of 90.1%.This work develops a repeatable and general method for the controlled construction of MOF coatings on various functional substrates and further fabricates carbon composites for ZICs with ultrastability.展开更多
A study was conducted to determine the effects of electrostatic field （ESF） treatment on seed germination and seedling growth of Sorbus pohuashanesis. The experiments were arranged by uniform design computed by the ...A study was conducted to determine the effects of electrostatic field （ESF） treatment on seed germination and seedling growth of Sorbus pohuashanesis. The experiments were arranged by uniform design computed by the Data Processing System （DPS）, including three levels of seeds soaking time, four levels of ESF intensity and four levels of ESF treatment time, with 12 treatments. Ten seeds were used in each treatment with three replicates. Seed vigor, seed germinating ability, emergence rate of seedling, survival rate of seedling, and seedling height and diameter, as well as the change in activities of superoxide dismutase （SOD）, soluble protein contents, total chlorophyll contents, soluble total sugar contents in leaves of S. pohuashanensis seedlings were measured after ESF treatments. The experiment results show that ESF treatment could improve the water absorption ability of dry seeds of S. pohuashanensis, resulting in fast germination at room temperature under light conditions. Combined treatment of ESF with cold stratification could increase seed germination percentage significantly （to 42.20%）, promote seedling height growth, affect leaf SOD activity, and could raise contents of total chlorophyll, soluble protein, and total soluble sugar in leaves. Seed soaking time had a significant effect on seed relative electroconductivity, seed germination under light, SOD activity, soluble protein content and total soluble sugar content of seedling leaves. ESF intensity exerted a moderate effect on these indexes. ESF treatment time only had significant effect on total chlorophyll contents, no evident effect on other indexes.展开更多
Photocatalytic dual-functional reaction under visible light irradiation represents a sustainable development strategy.In detail,H2production coupled with benzylamine oxidation can remarkably lower the cost by replacin...Photocatalytic dual-functional reaction under visible light irradiation represents a sustainable development strategy.In detail,H2production coupled with benzylamine oxidation can remarkably lower the cost by replacing sacrificial agents.In this work,Cd S quantum dots(Cd S QDs)were successfully loaded onto the surface of a porphyrinic metal-organic framework(Pd-PCN-222)by the electrostatic selfassembly at room temperature.The consequent Pd-PCN-222/CdS heterojunction composites displayed superb photocatalytic activity under visible light irradiation,achieving a H2production and benzylamine oxidation rate of 5069 and 3717μmol g^(-1)h^(-1)with>99%selectivity in 3 h.There is no noticeable loss of catalytic capability during three successive runs.Mechanistic studies by in situ electron spin resonance and X-ray photoelectron spectroscopy disclosed that CdS QDs injected photoexcited electrons to Pd-PCN-222 and then Zr6clusters under visible-light irradiation,and thus Cd S QDs and Zr6clusters behave as the photocatalytic oxidation and reduction centers,respectively.展开更多
As a potent anticancer drug,gambogic acid(GA)suffers from its poor water solubility and low chemical stability and shows a limited clinical outcome.To address this problem,we report here a simple and effective strateg...As a potent anticancer drug,gambogic acid(GA)suffers from its poor water solubility and low chemical stability and shows a limited clinical outcome.To address this problem,we report here a simple and effective strategy to immobilize and deliver GA using a reducible diblock poly(amino acid)as a model.The electrostatic interaction between GA and polymer enables a high drug loading content up to 53.6%.Moreover,the drug complexation induces a micelle-to-vesicle transformation,combined with a conformation tra nsition from random coil to a-helix.The hierarchically assembled drug nanocomplexes can serve as a smart carrier for efficient cell internalization and triggered release of multiple drugs under intracellular acidic and reductive conditions,resulting in a synergistic antitumor efficacy in vitro.This work provides a new insight into the drug-carrier interaction and a facile nanoplatform for drug delivery applications.展开更多
Horseradish peroxidase monolayer was assembled on the surface of PET-CO2 substrate. The reaction kinetics of HRP/PET film and H2O2 in micro reactor was studied using improved spectrophotometer. The relative activity ...Horseradish peroxidase monolayer was assembled on the surface of PET-CO2 substrate. The reaction kinetics of HRP/PET film and H2O2 in micro reactor was studied using improved spectrophotometer. The relative activity of self-assembly HRP/PET film still remains above 80% after storing for 150 days at 4℃. When applied to determination of H2O2 in sample, the recoveries of H2O2 are 96.5%~101.1%.展开更多
Nanoparticles self-assembly plays a pivotal role in designing new functional structural materials.The manipulation of interactions among nanoparticle building blocks is crucial for achieving assemblies with desired st...Nanoparticles self-assembly plays a pivotal role in designing new functional structural materials.The manipulation of interactions among nanoparticle building blocks is crucial for achieving assemblies with desired structures and properties.In this work,we assemble binary inorganic nanoparticles into alternating copolymer-like nanostructures by independently regulating hydrogen bonding and electrostatic interactions.The block copolymers grafted on nanoparticles feature oppositely charged groups,where electrostatic attraction drives the linear assembly of nanoparticles into alternate chain configurations.The hydrogen bonding interaction originates from the direct introduction of polyethylene glycol into the systems,serving as hydrogen bond acceptors with the grafted polymer and facilitating the side-by-side assembly of the chain structures.These two forces were observed to compete with each other during the assembly process,and could be precisely controlled by adjusting the quantities of acetic acid and polyethylene glycol,thus regulating the nanoparticle assembly behavior.This work provides a practical framework for the design of muti-force interactions in hierarchical colloid nanomaterials.展开更多
Low patency ratio of small-diameter vascular grafts remains a major challenge due to the occurrence of thrombosis formation and intimal hyperplasia after transplantation.Although developing the functional coating with...Low patency ratio of small-diameter vascular grafts remains a major challenge due to the occurrence of thrombosis formation and intimal hyperplasia after transplantation.Although developing the functional coating with release of bioactive molecules on the surface of small-diameter vascular grafts are reported as an effective strategy to improve their patency ratios,it is still difficult for current functional coatings cooperating with spatiotemporal control of bioactive molecules release to mimic the sequential requirements for antithrombogenicity and endothelialization.Herein,on basis of 3D-printed polyelectrolyte-based vascular grafts,a biologically inspired release system with sequential release in spatiotemporal coordination of dual molecules through an electrostatic self-assembly was first described.A series of tubes with tunable diameters were initially fabricated by a coaxial extrusion printing method with customized nozzles,in which a polyelectrolyte ink containing of ε-polylysine and sodium alginate was used.Further,dual bioactive molecules,heparin with negative charges and Tyr-Ile-Gly-Ser-Arg(YIGSR)peptide with positive charges were layer-by-layer assembled onto the surface of these 3D-printed tubes.Due to the electrostatic interaction,the sequential release of heparin and YIGSR was demonstrated and could construct a dynamic microenvironment that was thus conducive to the antithrombogenicity and endothelialization.This study opens a new avenue to fabricate a small-diameter vascular graft with a biologically inspired release system based on electrostatic interaction,revealing a huge potential for development of small-diameter artificial vascular grafts with good patency.展开更多
High-performance epoxy(EP)composites with excellent thermal conductivity and dielectric properties have attracted increasing attention for effective thermal management.In this work,three-dimensional(3D)structural func...High-performance epoxy(EP)composites with excellent thermal conductivity and dielectric properties have attracted increasing attention for effective thermal management.In this work,three-dimensional(3D)structural functional fillers were prepared by an electrostatic self-assembly approach.The negatively charged carbon nanotubes(nCNTs)prepared by carboxylation on the surface of CNTs were attached to the positively charged boron nitride(pBN)to form the 3D pBN@nCNTs functional fillers.The morphological characterizations of the formed 3D pBN@nCNTs fillers and epoxy composites were established,illustrating that nCNTs were linearly overlapped between the BN sheets,thus forming a 3D heat conduction network in the epoxy matrix.The synergistic effect of pBN with nCNTs on the enhancement of thermal conductivity and dielectric properties of composites was systematically studied.The experimental results demonstrated that the thermal conductivity of pBN@nCNTs/EP composites could reach 1.986 W m1K1 with the loading of 50 wt%fillers at 10:1 mass ratio of pBN:nCNTs,which is 464%and 124%higher than that of pure EP and BN/EP,respectively.Simultaneously,the dielectric permittivity was successfully increased to 15.14.Moreover,the thermal stability of the composites was synchronously enhanced.This study provides a facile path to fabricate thermosetting polymer composites with high thermal conductivity and dielectric properties.展开更多
The applications of nanotechnology in biomedicine have gained considerable attentions in recent years owing to the great enhancement of therapeutic efficiency.Integration of self-assembly into nanotechnology has broug...The applications of nanotechnology in biomedicine have gained considerable attentions in recent years owing to the great enhancement of therapeutic efficiency.Integration of self-assembly into nanotechnology has brought tremendous convenience during the formation of nano-carriers.Based on distinctive methods of self-assembly,nano-therapeutics have beer~developed to ar~impressive stage with the ability to perform site-specific delivery with temporal and spatial control.This review focuses on the recent advances in the preparing methods for nano-therapeutics,and their applications in the treatments of diseases.展开更多
The electrostatically self-assembly method is getting strategically important to prepare multilayer thin films. With careful choice of component materials, this method should allow for the preparation of multilayer th...The electrostatically self-assembly method is getting strategically important to prepare multilayer thin films. With careful choice of component materials, this method should allow for the preparation of multilayer thin films with a variety of excellent technological properties. Ti02/PSS multilayer thin films with ordered structure were prepared by electrostatic self-assembly method. UV-Vis-NIR spectrophotometer, X-ray photoelectron spectroscopy (XPS), and atom force microscopy (AFM) were used to characterize the structure and performance of the multilayer films. Because electrostatically self-assembly method allows molecular-level control over the film composition and thickness, this paper studied the responding depth of photocatalytic activity of Ti02 self-assembled films in detail.展开更多
基金support from the Science and Technology Program of Guangzhou(No.2024A04J2821)the National Natural Science Foundation of China(Nos.52222301,22171055)the Guangdong Natural Science Foundation for Distinguished Young Scholar(No.2022B1515020078)。
文摘Core-shell colloidal particles with a polymer layer have broad applications in different areas.Herein,we developed a two-step method combining aqueous surface-initiated photoinduced polymerization-induced self-assembly and photoinduced seeded reversible addition-fragmentation chain transfer(RAFT)polymerization to prepare a diverse set of core-shell colloidal particles with a well-defined polymer layer.Chemical compositions,structures,and thicknesses of polymer layers could be conveniently regulated by using different types of monomers and feed[monomer]/[chain transfer agent]ratios during seeded RAFT polymerization.
基金supported by the National Natural Science Foundation of China(No.51972198)Shandong Provincial Science and Technology Key Project(No.2018GGX104002)+7 种基金Taishan Scholars Program of Shandong Province(No.tsqn201812002)Independent Innovation Foundation of Shandong Universitythe State Key Program of National Natural Science of China(Nos.61633015,51532005)the Young Scholars Program of Shandong University(No.2016WLJH03),the Project of the Taishan Scholar(No.ts201511004)Shandong Provincial Natural Science Foundation(No.ZR2017MB001)Discipline Construction of High-Level Talents of Shandong University(No.31370089963078)1000 Talent Plan program(No.31370086963030)the National Natural Science Foundation of China(No.21371108)。
文摘Available onlineSilicon monoxide(SiO)is a promising anode material fo r lithium-ion batteries(LIBs)due to its high theoretical specific capacity(~2400 mAh/g),low working potential(<0.5 V vs.Li^+/Li),low cost,easy synthesis,nontoxicity,abundant natural source and smaller volume expansion than Si.However,low intrinsic electrical conductivity,low initial Coulombic efficiency(ICE)and inevitable volume expansion(~200%)impede its practical application.Here we fabricate SiO/wrinkled MXene composite(SiO-WM)by an electrostatic self-assembly method.Importantly,this method is simple,scalable and taking into account all the issues of SiO.As a result,the SiO-WM exhibits imp roved rate capability,cycling performance and ICE than bare SiO.
基金Funded by the Natural Science Foundation of Hebei Province, China (No. E2008000537)the Foundation for Development of Science and Technology of Hebei Province, China (No. 07215156)the Open Research Foundation of Key Laboratory of Advanced Civil Engineering Materials (Tongji University),Ministry of Education, China (No. 2010412)
文摘Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spectroscopy （FT-IR） and scanning electron microscopy （SEM）. Methyl orange was used to estimate the photocatalytic activity of the materials. The effects of the calcination temperature and silane dosage on the photocatalytic activity of the samples were investigated. The experimental results show that the bentonite facilitates the formation of anatase and restrains the transformation of anatase to rutile. Part of nano-size TiO2 particles insert into the galleries of bentonite. The photocatalysts exhibit a synergistic effect of adsorption and photocatalysis on methyl orange. Photocatalysts prepared by ESAM method exhibit higher photocatalytic activity and better recycle ability than those of the traditional method.
基金financially supported by the Fundamental Research Funds for the Central Universities (No. 2019XKQYMS16)
文摘Constructing electrode materials with large capacity and good conductivity is an effective approach to improve the capacitor performance of asymmetric supercapacitors(ASCs).In this paper,ZnCo_(2)S_(4)core-shell nanospheres are constructed by two-step hydrothermal method.In order to improve the chemical activity of ZnCo_(2)S_(4),ZnCo_(2)S_(4)is activated using cetyltrimethylammonium bromide(CTAB).Then,MXene nanosheets are fixed on the surface of ZnCo_(2)S_(4)by electrostatic selfassembly method to improve the specific surface area of ZnCo_(2)S_(4)and MXene-wrapped ZnCo_(2)S_(4)composite is prepared in this work.Owing to the synergy effect between MXene nanosheets and ZnCo_(2)S_(4)core-shell nanospheres,the as-prepared composite displays fast ion transfer rate and charge/discharge process.The capacity of the MXenewrapped ZnCo_(2)S_(4)composite can reach 1072 F·g^(-1),which is far larger than that of ZnCo_(2)S_(4)(407 F·g^(-1))at 1 A·g^(-1).An ASC device is assembled,which delivers 1.7 V potential window and superior cyclic stability(95.41%capacitance retention).Furthermore,energy density of this device is up to 30.46 Wh·kg^(-1)at a power density of850 W·kg^(-1).The above results demonstrate that MXenewrapped ZnCo_(2)S_(4)composite has great application prospects in electrochemical energy storage field.
基金National Natural Science Foundation of China (Nos. 21432004 and 21472023) for financial support
文摘The cooperative electrostatic attraction and π-π aromatic stacking interactions between tetrahedral tetrapyridinium TP and three tetraanionic tetraphenylethylene derivatives TPE-1～3 led to the formation of a new kind of supramolecular polymer networks in water, which have been confirmed by^1 H NMR,fluorescence, isothermal titration calorimetric(ITC) and dynamic light scattering(DLS) experiments. ITC studies show that the contributions of enthalpy and entropy were comparable, reflecting the importance of hydrophobicity in driving the intermolecular aromatic stacking. DLS experiments indicate that the linear supramolecular polymers formed by these tetratopic monomers further aggregated into networks of 10~2-nm size.
文摘Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (ESA) method. The whole self-assemble process, the function of surfactant and the effect of TiO_2 slurry′s concentration to the self-assemble were discussed. The isoelectric point of TiO_2 slurry measured by experiment is 6.8. The results show that whatever the concentration of the TiO_2 dispersion, a flat and compact adsorbed monolayer on the optic fiber can be built in a stable dispersion at lower pH. There is a adsorbed equilibrium on the substrate (fiber)/solution interface when enough time of incubation is given. A rough and loosen adsorbed layer is formed on the fiber surface by immersed the substrate in a high pH dispersion (pH>10) because the presence of hydroxyl on particle surface. Film thickness can be controlled by controlling the number of layers in the film.
基金This research was financially supported by China Scholar-ship Council and the Natural Science Foundation of Hubei Province (Project 2000J002)
文摘Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin films on si/icon and quartz substrates. The paniculate thin films were characterized by UV-vis spea-troscopy, surface, enhanced Raman scattering, atomic force microscopy and resistivity measurements. Due to the interparticle coupling between individual gold particles, an obvious collective particle plasmon resonance was ob-served on UV-vis spectra , and the particulate thin films exhibited a strong SERS effect. For multilayer thin films with a high particle coverage on substrates , resistivity of the order of 10-4 Ω·cm was yielded.
基金financial support from Project funded by National Natural Science Foundation of China(52172038,22179017)funding from Dalian University of Technology Open Fund for Large Scale Instrument Equipment
文摘Metal-organic framework(MOF)-derived carbon composites have been considered as the promising materials for energy storage.However,the construction of MOF-based composites with highly controllable mode via the liquid-liquid synthesis method has a great challenge because of the simultaneous heterogeneous nucleation on substrates and the self-nucleation of individual MOF nanocrystals in the liquid phase.Herein,we report a bidirectional electrostatic generated self-assembly strategy to achieve the precisely controlled coatings of single-layer nanoscale MOFs on a range of substrates,including carbon nanotubes(CNTs),graphene oxide(GO),MXene,layered double hydroxides(LDHs),MOFs,and SiO_(2).The obtained MOF-based nanostructured carbon composite exhibits the hierarchical porosity(V_(meso)/V_(micro)∶2.4),ultrahigh N content of 12.4 at.%and"dual electrical conductive networks."The assembled aqueous zinc-ion hybrid capacitor(ZIC)with the prepared nanocarbon composite as a cathode shows a high specific capacitance of 236 F g^(-1)at 0.5 A g^(-1),great rate performance of 98 F g^(-1)at 100 A g^(-1),and especially,an ultralong cycling stability up to 230000 cycles with the capacitance retention of 90.1%.This work develops a repeatable and general method for the controlled construction of MOF coatings on various functional substrates and further fabricates carbon composites for ZICs with ultrastability.
基金supported by the Key Technologies R&D Program of China during 2006–2010 (2006BAD03A04)
文摘A study was conducted to determine the effects of electrostatic field （ESF） treatment on seed germination and seedling growth of Sorbus pohuashanesis. The experiments were arranged by uniform design computed by the Data Processing System （DPS）, including three levels of seeds soaking time, four levels of ESF intensity and four levels of ESF treatment time, with 12 treatments. Ten seeds were used in each treatment with three replicates. Seed vigor, seed germinating ability, emergence rate of seedling, survival rate of seedling, and seedling height and diameter, as well as the change in activities of superoxide dismutase （SOD）, soluble protein contents, total chlorophyll contents, soluble total sugar contents in leaves of S. pohuashanensis seedlings were measured after ESF treatments. The experiment results show that ESF treatment could improve the water absorption ability of dry seeds of S. pohuashanensis, resulting in fast germination at room temperature under light conditions. Combined treatment of ESF with cold stratification could increase seed germination percentage significantly （to 42.20%）, promote seedling height growth, affect leaf SOD activity, and could raise contents of total chlorophyll, soluble protein, and total soluble sugar in leaves. Seed soaking time had a significant effect on seed relative electroconductivity, seed germination under light, SOD activity, soluble protein content and total soluble sugar content of seedling leaves. ESF intensity exerted a moderate effect on these indexes. ESF treatment time only had significant effect on total chlorophyll contents, no evident effect on other indexes.
基金support from the National Natural Science Foundation of China(Nos.21773314,21821003 and 21890382)the Guangdong Natural Science Funds for Distinguished Young Scholar(No.2019B151502017)。
文摘Photocatalytic dual-functional reaction under visible light irradiation represents a sustainable development strategy.In detail,H2production coupled with benzylamine oxidation can remarkably lower the cost by replacing sacrificial agents.In this work,Cd S quantum dots(Cd S QDs)were successfully loaded onto the surface of a porphyrinic metal-organic framework(Pd-PCN-222)by the electrostatic selfassembly at room temperature.The consequent Pd-PCN-222/CdS heterojunction composites displayed superb photocatalytic activity under visible light irradiation,achieving a H2production and benzylamine oxidation rate of 5069 and 3717μmol g^(-1)h^(-1)with>99%selectivity in 3 h.There is no noticeable loss of catalytic capability during three successive runs.Mechanistic studies by in situ electron spin resonance and X-ray photoelectron spectroscopy disclosed that CdS QDs injected photoexcited electrons to Pd-PCN-222 and then Zr6clusters under visible-light irradiation,and thus Cd S QDs and Zr6clusters behave as the photocatalytic oxidation and reduction centers,respectively.
基金supported by the National Natural Science Foundation of China(Nos.51873118,21474064,52022062)the KeyResearch and Development Program of Science and Technology Department of Sichuan Province(No.2019YFS0514)+2 种基金Science and Technology Project of Chengdu(No.2019-YF05-00784-SN)the Project of State Key Laboratory of Polymer Materials Engineering(No.sklpme2020-2-03)the Fundamental Research Funds for Central Universities。
文摘As a potent anticancer drug,gambogic acid(GA)suffers from its poor water solubility and low chemical stability and shows a limited clinical outcome.To address this problem,we report here a simple and effective strategy to immobilize and deliver GA using a reducible diblock poly(amino acid)as a model.The electrostatic interaction between GA and polymer enables a high drug loading content up to 53.6%.Moreover,the drug complexation induces a micelle-to-vesicle transformation,combined with a conformation tra nsition from random coil to a-helix.The hierarchically assembled drug nanocomplexes can serve as a smart carrier for efficient cell internalization and triggered release of multiple drugs under intracellular acidic and reductive conditions,resulting in a synergistic antitumor efficacy in vitro.This work provides a new insight into the drug-carrier interaction and a facile nanoplatform for drug delivery applications.
文摘Horseradish peroxidase monolayer was assembled on the surface of PET-CO2 substrate. The reaction kinetics of HRP/PET film and H2O2 in micro reactor was studied using improved spectrophotometer. The relative activity of self-assembly HRP/PET film still remains above 80% after storing for 150 days at 4℃. When applied to determination of H2O2 in sample, the recoveries of H2O2 are 96.5%~101.1%.
基金This work is financially supported by the Innovation Program of Shanghai Municipal Education Commission(No.2021-01-07-0007-E00073)the National Natural Science Foundation of China(Nos.52125308 and 52293473)+3 种基金the Shanghai Municipal Science and Technology Project(No.23JC1400100)the National Key Research&Development Program of China(No.2022YFA1404700)the Shanghai Pujiang Program(No.23PJ1401000)China Postdoctoral Science Foundation(No.2022M720754).
文摘Nanoparticles self-assembly plays a pivotal role in designing new functional structural materials.The manipulation of interactions among nanoparticle building blocks is crucial for achieving assemblies with desired structures and properties.In this work,we assemble binary inorganic nanoparticles into alternating copolymer-like nanostructures by independently regulating hydrogen bonding and electrostatic interactions.The block copolymers grafted on nanoparticles feature oppositely charged groups,where electrostatic attraction drives the linear assembly of nanoparticles into alternate chain configurations.The hydrogen bonding interaction originates from the direct introduction of polyethylene glycol into the systems,serving as hydrogen bond acceptors with the grafted polymer and facilitating the side-by-side assembly of the chain structures.These two forces were observed to compete with each other during the assembly process,and could be precisely controlled by adjusting the quantities of acetic acid and polyethylene glycol,thus regulating the nanoparticle assembly behavior.This work provides a practical framework for the design of muti-force interactions in hierarchical colloid nanomaterials.
基金The authors gratefully acknowledge the support for this work from the National Key research and Development Program(Grant No.2018YFA0703100)the National Natural Science Foundation of China(Grant Nos.82072082,31900959)+2 种基金the Youth Innovation Promotion Association of CAS(Grant No.2019350)the Guangdong Natural Science Foundation(Grant No.2019A1515011277)the Shenzhen Fundamental Research Foundation(Grant No.JCYJ20180507182237428).
文摘Low patency ratio of small-diameter vascular grafts remains a major challenge due to the occurrence of thrombosis formation and intimal hyperplasia after transplantation.Although developing the functional coating with release of bioactive molecules on the surface of small-diameter vascular grafts are reported as an effective strategy to improve their patency ratios,it is still difficult for current functional coatings cooperating with spatiotemporal control of bioactive molecules release to mimic the sequential requirements for antithrombogenicity and endothelialization.Herein,on basis of 3D-printed polyelectrolyte-based vascular grafts,a biologically inspired release system with sequential release in spatiotemporal coordination of dual molecules through an electrostatic self-assembly was first described.A series of tubes with tunable diameters were initially fabricated by a coaxial extrusion printing method with customized nozzles,in which a polyelectrolyte ink containing of ε-polylysine and sodium alginate was used.Further,dual bioactive molecules,heparin with negative charges and Tyr-Ile-Gly-Ser-Arg(YIGSR)peptide with positive charges were layer-by-layer assembled onto the surface of these 3D-printed tubes.Due to the electrostatic interaction,the sequential release of heparin and YIGSR was demonstrated and could construct a dynamic microenvironment that was thus conducive to the antithrombogenicity and endothelialization.This study opens a new avenue to fabricate a small-diameter vascular graft with a biologically inspired release system based on electrostatic interaction,revealing a huge potential for development of small-diameter artificial vascular grafts with good patency.
基金National Key Research and Development Program of China(2017YFB0903804)Science and Technology Program of the State Grid Corporation of China(No.5455DW170026).
文摘High-performance epoxy(EP)composites with excellent thermal conductivity and dielectric properties have attracted increasing attention for effective thermal management.In this work,three-dimensional(3D)structural functional fillers were prepared by an electrostatic self-assembly approach.The negatively charged carbon nanotubes(nCNTs)prepared by carboxylation on the surface of CNTs were attached to the positively charged boron nitride(pBN)to form the 3D pBN@nCNTs functional fillers.The morphological characterizations of the formed 3D pBN@nCNTs fillers and epoxy composites were established,illustrating that nCNTs were linearly overlapped between the BN sheets,thus forming a 3D heat conduction network in the epoxy matrix.The synergistic effect of pBN with nCNTs on the enhancement of thermal conductivity and dielectric properties of composites was systematically studied.The experimental results demonstrated that the thermal conductivity of pBN@nCNTs/EP composites could reach 1.986 W m1K1 with the loading of 50 wt%fillers at 10:1 mass ratio of pBN:nCNTs,which is 464%and 124%higher than that of pure EP and BN/EP,respectively.Simultaneously,the dielectric permittivity was successfully increased to 15.14.Moreover,the thermal stability of the composites was synchronously enhanced.This study provides a facile path to fabricate thermosetting polymer composites with high thermal conductivity and dielectric properties.
基金financially supported by the Thousand Talents Program for Young Professionalsthe National Natural Science Foundation of China(No.51673100)the Fundamental Research Funds for the Central Universities
文摘The applications of nanotechnology in biomedicine have gained considerable attentions in recent years owing to the great enhancement of therapeutic efficiency.Integration of self-assembly into nanotechnology has brought tremendous convenience during the formation of nano-carriers.Based on distinctive methods of self-assembly,nano-therapeutics have beer~developed to ar~impressive stage with the ability to perform site-specific delivery with temporal and spatial control.This review focuses on the recent advances in the preparing methods for nano-therapeutics,and their applications in the treatments of diseases.
基金the National Natural ScienceFoundation of China(No.59982002) Foundation of National Key Lab.of Advanced Metal Materials.
文摘The electrostatically self-assembly method is getting strategically important to prepare multilayer thin films. With careful choice of component materials, this method should allow for the preparation of multilayer thin films with a variety of excellent technological properties. Ti02/PSS multilayer thin films with ordered structure were prepared by electrostatic self-assembly method. UV-Vis-NIR spectrophotometer, X-ray photoelectron spectroscopy (XPS), and atom force microscopy (AFM) were used to characterize the structure and performance of the multilayer films. Because electrostatically self-assembly method allows molecular-level control over the film composition and thickness, this paper studied the responding depth of photocatalytic activity of Ti02 self-assembled films in detail.
