Poly(γ-glutamic acid)(γ-PGA)has been found widespread applications in biomedical field because of its excellent water solubility,biocompatibility,and bioactivity.Herein,a water-insoluble γ-PGA antibacterial compoun...Poly(γ-glutamic acid)(γ-PGA)has been found widespread applications in biomedical field because of its excellent water solubility,biocompatibility,and bioactivity.Herein,a water-insoluble γ-PGA antibacterial compound is facilely fabricated via one-pot electrostatic assembly of γ-PGA with cationic ethyl lauroyl arginate(ELA).The functionalized γ-PGA compound(γ-PGA-ELA)ethanol solution can facilely produce colorless and transparent coatings on various inorganic,metal,and polymeric substrates,especially for the lumen of slender catheters(length up to 2 m,and inner diameter down to 1 mm).The functionalized γ-PGA coating presents remarkable antibacterial efficacy in vitro and in vivo.In addition,the γ-PGA compound is used as antibacterial additives of polyolefin via melting extrusion,and the asprepared antibacterial polyolefin demonstrates advantageous antibacterial efficacy.More importantly,the functionalized γ-PGA coating exhibit good hemocompatibility,low cytotoxicity,and satisfactory histocompatibility.The as-proposed γ-PGA compound has a great potential to serve as a safe and multifunctional antibacterial candidate to combat biomedical devices-related infections.展开更多
Recently discovered bismuth oxychalcogenide(Bi_(2) O_(2) Se) has aroused great interest due to its ultrahigh carrier mobility,tunable band gap and good environmental stability,making it a promising candidate for high-...Recently discovered bismuth oxychalcogenide(Bi_(2) O_(2) Se) has aroused great interest due to its ultrahigh carrier mobility,tunable band gap and good environmental stability,making it a promising candidate for high-performance electronics and optoelectronics.Their synthesis by colloidal approaches represents a cost-effective alternative to well-established chemical vapor deposition methods,and the resulting electronic-grade inks are important for large-area printed or wearable electronics.However,it is still challenging to control the colloidal growth of Bi_(2) O_(2) Se nanosheets in solution in addition to their assembly into high-performance thin films.Here,we report a two-step colloidal synthesis of Bi_(2) O_(2) Se nanosheets by separating the seeding and growth steps,thereby achieving controllable production of nanosheets with a lateral size of 1.4 mm and a thickness of 10 nm at optimized reaction conditions.These Bi_(2) O_(2) Se nanosheets are electrostatically assembled into large-area thin films,from which a photodetector is fabricated with a responsivity of 6.1 A/W and a short response time of 368 ms under the 520-nm laser illumination.The device exhibits fast response to modulations as high as 100 k Hz,along with a à3 dB bandwidth of 1 kHz.This work provides an important understanding of the controlled colloidal synthesis of Bi_(2) O_(2) Se nanosheets,and demonstrates their potential applications in fast photodetectors.展开更多
The haemocompatibility of Ti-3Zr-2Sn-3Mo-25Nb biomedical alloy was studied after surface heparinization. A layer of sol-gel TiO2 films was applied on the alloy samples followed by active treatment in the bio-functiona...The haemocompatibility of Ti-3Zr-2Sn-3Mo-25Nb biomedical alloy was studied after surface heparinization. A layer of sol-gel TiO2 films was applied on the alloy samples followed by active treatment in the bio-functionalized solution for introducing the OH- and groups, and then the heparin was immobilized on the active TiO2 films through the electrostatic self assembly technology. It is shown that the heparinized films are mainly composed of anatase and rutile with smooth and dense surface. In vitro blood compatibility was evaluated by haemolysis test, clotting time and platelet adhesion behavior tests. The results show that the haemocompatibility of the alloy could be significantly improved by surface heparinization.展开更多
MXene is a new 2D transition metal carbide possessing metallic conductivity and hydrophilic surfaces.It has drawn widespread attention as a potential material for electrode use.However,the applications of MXene are li...MXene is a new 2D transition metal carbide possessing metallic conductivity and hydrophilic surfaces.It has drawn widespread attention as a potential material for electrode use.However,the applications of MXene are limited by its property of low electrical capacity.In this paper,a novel MnO_(2)/MXene composite is prepared by electrostatic self-assembly.Firstly,delaminated MnO_(2)nanosheets are obtained through the intercalation delamination of multilayered H-MnO_(2)in a cationic Gemini surfactant(Gem)solution,leading to a positively charged surface.Then,the positive MnO_(2)nanosheets are assembled on negative MXene nanosheets through electrostatic self-assembly to form a MnO_(2)/MXene composite.The characterization results show that the MnO_(2)nanosheets are intimately assembled on the MXene nanosheets.As an electrode material,the MnO_(2)/MXene composite displays a specific capacitance of 340 F g^(−1)at 1 A g^(−1),which is three times the performance of an MXene electrode.In addition,the MnO_(2)/MXene electrode shows a high retention rate(90.3%retention at 10 A g^(−1))and good cycling life(87.6%of the initial specific capacitance is retained after 2000 cycles at 4 A g^(−1)).The properties of the proposed composite are attributed to the excellent conductivity of MXene and the high specific capacitance of MnO_(2).展开更多
NiMo-based catalysts show significant potential for the hydrogen evolution reaction(HER).Optimizing the electronic structure and enhancing mass transfer are two critical factors for improving catalytic performance,but...NiMo-based catalysts show significant potential for the hydrogen evolution reaction(HER).Optimizing the electronic structure and enhancing mass transfer are two critical factors for improving catalytic performance,but they remain significant challenges.Herein,we present a route for synthesizing two-dimensional(2D)porous Mo_(2)N-Ni heterojunction nanosheets with tuned Ni-Mo ratio for enhanced alkaline HER performance.A precursor can be easily synthesized by assembling polyoxometalate clusters(PMo_(12))with layered hydroxy oxides(Ni(OH)_(2)).It is found that the interaction between PMo_(12)and Ni(OH)_(2)can effectively protect the particles from significant agglomeration during pyrolysis,resulting in the formation of 2D porous sheets composed of small Mo_(2)N-Ni units.The transfer of electrons from Ni to Mo_(2)N results in the redistribution of electrons at the heterojunction,optimizing the adsorption and desorption of intermediates.Moreover,the 2D porous structure comprised of small particles enhances mass transfer,thereby reducing the impedance of the catalyst.Consequently,the catalyst with an optimized Mo/Ni ratio exhibits an overpotential of 19 mV at 10 mA cm^(-2),being comparable to that of commercial Pt/C catalyst.The anion exchange membrane(AEM)electrolyzer,consisting of optimized Mo_(2)N-Ni and NiFe-LDH,achieves a current density of 500 mA cm^(-2)at 1.80 V and can operate stably for 300 h.This assembly method offers an effective strategy for the large-scale preparation of efficient catalysts.展开更多
Lithium-sulfur batteries are one of the most promising next-generation energy storage systems,while their real application is largely limited by the shuttle effect of lithium poly sulfides(LiPSs).Herein,an interlayer ...Lithium-sulfur batteries are one of the most promising next-generation energy storage systems,while their real application is largely limited by the shuttle effect of lithium poly sulfides(LiPSs).Herein,an interlayer based on a heterostructure consisting of MXene and two-dimensional montmorillonite(MXene@MMT) is developed via an electrostatic self-assembly strategy.Such a hetero structure possesses strong adsorption ability for LiPSs and can accelerate the conversion reaction from liquid LiPSs to solid Li2S in virtue of its strong adsorption,high conductivity,and good catalytic activity.Furthermore,this hetero structure not only effectively blocks the migration of poly sulfides,but also provides low energy barrier and rich pathways for Li^(+)transport.Ultimately,the asassembled Li-S batteries with the MXene@MMT based interlayer deliver a high initial discharge capacity of 1375.5 mAh g^(-1) at 0.1C and long-term cycling stability with 500 mAh g^(-1) remaining over 500 cycles under a high rate of 2C.In a practical demonstration,the as-sembled soft pack battery achieved an initial discharge capacity of 733 mAh g^(-1) at 0.1 C and still retained a high capacity of 402 mAh g^(-1) after 100 cycles.展开更多
Transition metal chalcogenides(TMCs)have been well-established as ideal low-dimensional systems for photocatalytic hydrogen evolution.Strategies toward improving the activity of these TMC photocatalysts by crafting he...Transition metal chalcogenides(TMCs)have been well-established as ideal low-dimensional systems for photocatalytic hydrogen evolution.Strategies toward improving the activity of these TMC photocatalysts by crafting heterostructures have been intensively studied.In this study,a two-dimensional(2D)CoAl layered double hydroxide(CoAl-LDH)has been assembled on 2D TMCs(CdIn_(2)S_(4),In_(2)S_(3),and ZnIn_(2)S_(4))to construct novel 2D/2D heterostructures by a facile electrostatic assembly method.The intimate interaction at the interface of hybrids and the suitable energy level alignment enable an efficient pathway for electron transfer to improve the photoactivity.Experimental results show that the photocatalytic activity of the CdIn_(2)S_(4)@CoAl-LDH hybrids for H_(2)production is about 4.3 times higher than that of CdIn_(2)S_(4)nanosheets under visible-light irradiation.The effect of 2D CoAl-LDH on enhancing the photoactivities of In_(2)S_(3)and ZnIn_(2)S_(4)by similarly constructing 2D heterostructures has also been determined.This work establishes a foundation to construct 2D TMC-based heterostructures using CoAl-LDH nanosheets toward enhanced photoredox activity.展开更多
As nano-sized molecular oxides,polyoxometalates(POMs)hold great promise in non-volatile memory materials based on redox-active molecules.Materials processed from solution,by drop-casting,by embedding POMs in polymers,...As nano-sized molecular oxides,polyoxometalates(POMs)hold great promise in non-volatile memory materials based on redox-active molecules.Materials processed from solution,by drop-casting,by embedding POMs in polymers,or using layer-by-layer deposition techniques have thus been reported and successfully investigated.Almost all of these examples are electrostatically assembled materials.We herein propose an original route for the elaboration of robust covalent POM networks.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.51973221 and 51873213)the Youth Innovation Promotion Association of CAS(No.2017269)+1 种基金the Major Science and Technology Innovation Project of Shandong Province(No.2019JZZY011105)the High-Tech Research&Development Program of CAS-WEGO Group。
文摘Poly(γ-glutamic acid)(γ-PGA)has been found widespread applications in biomedical field because of its excellent water solubility,biocompatibility,and bioactivity.Herein,a water-insoluble γ-PGA antibacterial compound is facilely fabricated via one-pot electrostatic assembly of γ-PGA with cationic ethyl lauroyl arginate(ELA).The functionalized γ-PGA compound(γ-PGA-ELA)ethanol solution can facilely produce colorless and transparent coatings on various inorganic,metal,and polymeric substrates,especially for the lumen of slender catheters(length up to 2 m,and inner diameter down to 1 mm).The functionalized γ-PGA coating presents remarkable antibacterial efficacy in vitro and in vivo.In addition,the γ-PGA compound is used as antibacterial additives of polyolefin via melting extrusion,and the asprepared antibacterial polyolefin demonstrates advantageous antibacterial efficacy.More importantly,the functionalized γ-PGA coating exhibit good hemocompatibility,low cytotoxicity,and satisfactory histocompatibility.The as-proposed γ-PGA compound has a great potential to serve as a safe and multifunctional antibacterial candidate to combat biomedical devices-related infections.
基金supported by National Science Foundations of China (Nos.51873088, 12004195)Natural Science Foundations of Tianjin (No.20JCQNJC01820)+2 种基金Tianjin Municipal Science and Technology Commission (No.18JCZDJC38400)“111” Project of China’s Higher Education (No.B18030)Fundamental Research Funds for the Central Universities from Nankai University (No.63201061)。
文摘Recently discovered bismuth oxychalcogenide(Bi_(2) O_(2) Se) has aroused great interest due to its ultrahigh carrier mobility,tunable band gap and good environmental stability,making it a promising candidate for high-performance electronics and optoelectronics.Their synthesis by colloidal approaches represents a cost-effective alternative to well-established chemical vapor deposition methods,and the resulting electronic-grade inks are important for large-area printed or wearable electronics.However,it is still challenging to control the colloidal growth of Bi_(2) O_(2) Se nanosheets in solution in addition to their assembly into high-performance thin films.Here,we report a two-step colloidal synthesis of Bi_(2) O_(2) Se nanosheets by separating the seeding and growth steps,thereby achieving controllable production of nanosheets with a lateral size of 1.4 mm and a thickness of 10 nm at optimized reaction conditions.These Bi_(2) O_(2) Se nanosheets are electrostatically assembled into large-area thin films,from which a photodetector is fabricated with a responsivity of 6.1 A/W and a short response time of 368 ms under the 520-nm laser illumination.The device exhibits fast response to modulations as high as 100 k Hz,along with a à3 dB bandwidth of 1 kHz.This work provides an important understanding of the controlled colloidal synthesis of Bi_(2) O_(2) Se nanosheets,and demonstrates their potential applications in fast photodetectors.
基金Project (31100693/C100302) supported by the National Natural Science Foundation of ChinaProject (31011120049) supported by the Australia-China Special Fund, International Science Linkages Program co-supported by the Department of Innovation, Industry, Science and Research of Australia, and the Ministry of Science and Technology and National Science Foundation of China+1 种基金Project(2010ZDKG-96) supported by the Major Subject of "13115" Programs of Shaan’xi Province, ChinaProject (2012CB619102) supported by the National Basic Research Program of China
文摘The haemocompatibility of Ti-3Zr-2Sn-3Mo-25Nb biomedical alloy was studied after surface heparinization. A layer of sol-gel TiO2 films was applied on the alloy samples followed by active treatment in the bio-functionalized solution for introducing the OH- and groups, and then the heparin was immobilized on the active TiO2 films through the electrostatic self assembly technology. It is shown that the heparinized films are mainly composed of anatase and rutile with smooth and dense surface. In vitro blood compatibility was evaluated by haemolysis test, clotting time and platelet adhesion behavior tests. The results show that the haemocompatibility of the alloy could be significantly improved by surface heparinization.
基金supported by the research funds for the National Natural Science Foundation of China(21606081).
文摘MXene is a new 2D transition metal carbide possessing metallic conductivity and hydrophilic surfaces.It has drawn widespread attention as a potential material for electrode use.However,the applications of MXene are limited by its property of low electrical capacity.In this paper,a novel MnO_(2)/MXene composite is prepared by electrostatic self-assembly.Firstly,delaminated MnO_(2)nanosheets are obtained through the intercalation delamination of multilayered H-MnO_(2)in a cationic Gemini surfactant(Gem)solution,leading to a positively charged surface.Then,the positive MnO_(2)nanosheets are assembled on negative MXene nanosheets through electrostatic self-assembly to form a MnO_(2)/MXene composite.The characterization results show that the MnO_(2)nanosheets are intimately assembled on the MXene nanosheets.As an electrode material,the MnO_(2)/MXene composite displays a specific capacitance of 340 F g^(−1)at 1 A g^(−1),which is three times the performance of an MXene electrode.In addition,the MnO_(2)/MXene electrode shows a high retention rate(90.3%retention at 10 A g^(−1))and good cycling life(87.6%of the initial specific capacitance is retained after 2000 cycles at 4 A g^(−1)).The properties of the proposed composite are attributed to the excellent conductivity of MXene and the high specific capacitance of MnO_(2).
基金supported by the National Key R&D Program of China(2022YFA1503002,2022YFA1503003)the National Natural Science Foundation of China(22271081)+2 种基金the Natural Science Foundation of Heilongjiang Province(PL2024B017)the Postdoctoral Science Foundation of Heilongjiang Province(LBH-Z22240)the Heilongjiang University Excellent Youth Foundation。
文摘NiMo-based catalysts show significant potential for the hydrogen evolution reaction(HER).Optimizing the electronic structure and enhancing mass transfer are two critical factors for improving catalytic performance,but they remain significant challenges.Herein,we present a route for synthesizing two-dimensional(2D)porous Mo_(2)N-Ni heterojunction nanosheets with tuned Ni-Mo ratio for enhanced alkaline HER performance.A precursor can be easily synthesized by assembling polyoxometalate clusters(PMo_(12))with layered hydroxy oxides(Ni(OH)_(2)).It is found that the interaction between PMo_(12)and Ni(OH)_(2)can effectively protect the particles from significant agglomeration during pyrolysis,resulting in the formation of 2D porous sheets composed of small Mo_(2)N-Ni units.The transfer of electrons from Ni to Mo_(2)N results in the redistribution of electrons at the heterojunction,optimizing the adsorption and desorption of intermediates.Moreover,the 2D porous structure comprised of small particles enhances mass transfer,thereby reducing the impedance of the catalyst.Consequently,the catalyst with an optimized Mo/Ni ratio exhibits an overpotential of 19 mV at 10 mA cm^(-2),being comparable to that of commercial Pt/C catalyst.The anion exchange membrane(AEM)electrolyzer,consisting of optimized Mo_(2)N-Ni and NiFe-LDH,achieves a current density of 500 mA cm^(-2)at 1.80 V and can operate stably for 300 h.This assembly method offers an effective strategy for the large-scale preparation of efficient catalysts.
基金financially supported by National Natural Science Foundation of China(Nos.52372185 and 51972070)Guizhou Provincial High Level Innovative Talents Project(No.QKHPTRC-GCC[2022]013-1)+4 种基金the Innovation Team for Advanced Electrochemical Energy Storage Devices and Key Materials of Guizhou Provincial Higher Education Institutions(No.QianJiaoJi[2023]054)the Advanced Electrochemical Energy Storage Devices and Key Materials Technology Innovation Talent Team Construction of Guizhou Province(No.QKHPTRC-CXTD[2023]016)Guizhou Provincial Basic Research Program(Natural Science)(No.QKHJC-ZK[2024]YB608)Guizhou Province Science and Technology Plan Project-Basic Research Program(Natural Sciences)Talent Team Support Project(No.QianKeHeQNB[2025]003)Shenzhen Science and Technology Program(No.KQTD20210811090112002)
文摘Lithium-sulfur batteries are one of the most promising next-generation energy storage systems,while their real application is largely limited by the shuttle effect of lithium poly sulfides(LiPSs).Herein,an interlayer based on a heterostructure consisting of MXene and two-dimensional montmorillonite(MXene@MMT) is developed via an electrostatic self-assembly strategy.Such a hetero structure possesses strong adsorption ability for LiPSs and can accelerate the conversion reaction from liquid LiPSs to solid Li2S in virtue of its strong adsorption,high conductivity,and good catalytic activity.Furthermore,this hetero structure not only effectively blocks the migration of poly sulfides,but also provides low energy barrier and rich pathways for Li^(+)transport.Ultimately,the asassembled Li-S batteries with the MXene@MMT based interlayer deliver a high initial discharge capacity of 1375.5 mAh g^(-1) at 0.1C and long-term cycling stability with 500 mAh g^(-1) remaining over 500 cycles under a high rate of 2C.In a practical demonstration,the as-sembled soft pack battery achieved an initial discharge capacity of 733 mAh g^(-1) at 0.1 C and still retained a high capacity of 402 mAh g^(-1) after 100 cycles.
基金supported by the National Natural Science Foundation of China(52071137,51977071,51802040,and 21802020)the Science and Technology Innovation Program of Hunan Province(2021RC3066 and 2021RC3067)+1 种基金the Natural Science Foundation of Hunan Province(2020JJ3004 and 2020JJ4192)N.Zhang and X.Xie also acknowledge the financial support from the Fundamental Research Funds for the Central Universities.
文摘Transition metal chalcogenides(TMCs)have been well-established as ideal low-dimensional systems for photocatalytic hydrogen evolution.Strategies toward improving the activity of these TMC photocatalysts by crafting heterostructures have been intensively studied.In this study,a two-dimensional(2D)CoAl layered double hydroxide(CoAl-LDH)has been assembled on 2D TMCs(CdIn_(2)S_(4),In_(2)S_(3),and ZnIn_(2)S_(4))to construct novel 2D/2D heterostructures by a facile electrostatic assembly method.The intimate interaction at the interface of hybrids and the suitable energy level alignment enable an efficient pathway for electron transfer to improve the photoactivity.Experimental results show that the photocatalytic activity of the CdIn_(2)S_(4)@CoAl-LDH hybrids for H_(2)production is about 4.3 times higher than that of CdIn_(2)S_(4)nanosheets under visible-light irradiation.The effect of 2D CoAl-LDH on enhancing the photoactivities of In_(2)S_(3)and ZnIn_(2)S_(4)by similarly constructing 2D heterostructures has also been determined.This work establishes a foundation to construct 2D TMC-based heterostructures using CoAl-LDH nanosheets toward enhanced photoredox activity.
基金supported by Sorbonne Universiteby the CNRS.W.C.Poh was supported by the scholarship awarded by Nanyang Technological University,Singapore.
文摘As nano-sized molecular oxides,polyoxometalates(POMs)hold great promise in non-volatile memory materials based on redox-active molecules.Materials processed from solution,by drop-casting,by embedding POMs in polymers,or using layer-by-layer deposition techniques have thus been reported and successfully investigated.Almost all of these examples are electrostatically assembled materials.We herein propose an original route for the elaboration of robust covalent POM networks.
基金the support from the National Natural Science Foundation of China(NSFC)(U20A20128,52263027,22379060,52173169 and 52222312)the"Double Thousand Plan"Science and Technology Innovation High-end Talent Project of Jiangxi Province(jxsq2019201049)+2 种基金the Natural Science Foundation of Jiangxi Province(20231ZDH04036,20212BAB214055 and 20224ACB204007)China National Postdoctoral Program for Innovative Talents(BX2021117)China Postdoctoral Science Foundation(2021M700060)。
